Silverton City Zoning Code
ARTICLE 3
COMMUNITY DESIGN STANDARDS
§ 3.0.100 Design standards – Purpose.
The following provisions describe how to apply the provisions of this article and the relationship between this article and the land use provisions in Article 2.
(Ord. 08-06 § 3, 2008)
§ 3.0.200 Design standards – Applicability.
This article is applied differently based on whether a project is classified as a major project or a minor project. In addition to the following criteria, each chapter of this article contains “applicability” directions.
A.
Major Project. Major projects are those that require design review (Chapter 4.2 SDC), land division (Chapter 4.3 SDC), conditional use review (Chapter 4.4 SDC), or planned development (Chapter 4.5 SDC) approval. Such projects must conform to the applicable sections of all of the following chapters:
1.
Land use district standards (Article 2).
2.
Access and Circulation (Chapter 3.1 SDC).
3.
Landscaping, Street Trees, Fences and Walls (Chapter 3.2 SDC).
4.
Parking and Loading (Chapter 3.3 SDC).
5.
Public Facilities (Chapter 3.4 SDC).
6.
Historic Landmarks (Chapter 3.5 SDC).
B.
Minor Project. Minor projects are small developments and land use approvals that do not require public improvements, and those that do not fall under the major project criteria, such as land use reviews. In general, the following chapters apply. (Some individual sections may not apply.)
1.
Land use district standards (Article 2).
2.
Access and Circulation (Chapter 3.1 SDC).
3.
Landscaping, Street Trees, Fences and Walls (Chapter 3.2 SDC).
4.
Parking and Loading (Chapter 3.3 SDC).
5.
Historic Landmarks (Chapter 3.5 SDC).
C.
Nonconforming Situations. See Chapter 5.2 SDC for provisions related to nonconforming uses and developments.
(Ord. 08-06 § 3, 2008)
§ 3.1.100 Purpose.
The purpose of this chapter is to ensure that developments provide safe and efficient access and circulation for pedestrians and vehicles. SDC § 3.1.200 provides standards for vehicular access and circulation. SDC § 3.1.300 provides standards for pedestrian access and circulation. General street improvement requirements are provided in SDC § 3.4.100, with more specific requirements provided in the city of Silverton transportation system plan and the city’s public works design standards.
(Ord. 08-06 § 3, 2008)
§ 3.1.200 Vehicular access and circulation.
A.
Intent and Purpose. This section implements the access management policies of the city of Silverton transportation system plan. The intent of this section is to manage vehicular access and on-site circulation to ensure the continued operational safety, capacity and function of the transportation system.
B.
Applicability. This section applies to vehicle access(es) and on-site circulation facilities in the city of Silverton. This section applies when lots are created, consolidated, or modified through a land division, partition, lot line adjustment, lot consolidation, or street vacation; when development is subject to land use review or design review; and when changes are proposed to existing regulations that will result in significant changes to access and circulation. Access to a designated state or county highway is subject to the provisions of this section and the requirements of the applicable roadway authority. Where regulations of the city conflict with those of the roadway authority, the more restrictive requirements apply.
C.
Access Permit Required. Access to a public street (e.g., a new curb cut or driveway approach) requires an access permit. An access permit may be in the form of a letter from the roadway authority to the applicant, or it may be attached to a land use decision notice as a condition of approval. In either case, approval of an access permit shall follow the procedures and requirements of the applicable roadway authority, as determined through the review procedures in Article 4.
D.
Traffic Impact Study Requirements. The public works director may require a traffic study prepared by a registered traffic engineer to determine access, circulation, and other transportation requirements in conformance with SDC § 4.1.900, Traffic impact studies.
E.
Conditions of Approval. The public works director or other road authority may require the closing or consolidation of existing curb cuts or other vehicle access points, recording of reciprocal access easements (i.e., for shared driveways), development of a frontage street, installation of traffic control devices, right-in-right-out-only approaches, medians, dedicated turn lanes, provision for future mitigation opportunities by land dedication or easement, and/or other mitigation as a condition of granting an access permit to ensure the safe and efficient operation of the street and highway system.
F.
Corner and Intersection Separation – Backing onto Public Streets. New and modified accesses shall conform to the following standards:
1.
Except as provided under subsection (F)(4) of this section, the distance between street intersections or other street accesses shall meet the minimum spacing requirements as provided in the transportation system plan.
2.
New property access shall be subject to the design requirements of the transportation system plan and public works design standards. The public works director may limit or require the closure and/or combination of driveway approaches, and/or impose turning restrictions (i.e., right in/out, right in only, or right out only), consistent with public works design standards or those of other roadway authorities, as applicable.
3.
Vehicular access to and from off-street parking areas shall not permit backing onto a public street, except as allowed through design review or a planned development approval. (Single-family dwellings and duplex dwellings are exempt.)
4.
The roadway authority may reduce the required separation distance of access points where the standard would otherwise result in a taking of private property, or conformance to the standard is not feasible due to existing lot dimensions, development, other physical features, or conflicting code requirements (e.g., driveway grade requirements, or building or fire code requirements). Where the roadway authority finds that reducing the separation distance is warranted, the total number of access points to the site shall be limited to the minimum necessary to provide reasonable access and shared/joint access may be required.
G.
Site Circulation. New developments shall be required to provide a circulation system that accommodates expected traffic generated from development. Pedestrian connections, including connections through large sites, connections between sites (as applicable), and to adjacent sidewalks, must be provided and shall conform to SDC § 3.1.300.
H.
Joint and Cross-Access – Requirements. The number of driveway and private street intersections with public streets shall be minimized by the use of shared driveway approaches for adjoining commercial, industrial and multifamily developments, and for other uses where they abut a collector or arterial street. When necessary for traffic safety and access management purposes, or to access flag lots, the city may require joint access and/or shared driveways in the following situations:
1.
For shared parking areas.
2.
For adjacent developments, where access onto an arterial or collector street is limited and access spacing standards cannot otherwise be met.
3.
For multi-tenant developments, and developments on multiple lots or parcels. Such joint accesses and shared driveways shall incorporate all of the following:
a.
A continuous service drive or cross-access corridor that provides for driveway separation consistent with the applicable roadway authority’s access management classification system and standards;
b.
A design speed of 10 miles per hour and a maximum width of 20 feet, in addition to any parking alongside the driveway; additional driveway width or fire lanes may be approved when necessary to accommodate specific types of service vehicles, loading vehicles, or emergency service provider vehicles;
c.
Driveway stubs to property lines (for future extension), turnarounds, and other design features to address emergency access requirements and to make apparent that the abutting properties may be required with future development to connect to the cross-access driveway.
I.
Joint and Cross-Access – Reduction in Required Parking Allowed. When a shared driveway is provided or required as a condition of approval, the land uses adjacent to the shared driveway may have their minimum parking standards reduced in accordance with the shared parking provisions of SDC § 3.3.300(D).
J.
Joint and Cross-Access – Easement and Use and Maintenance Agreement. Pursuant to this section, and concurrent with final plat recordation, property owners sharing an access drive must provide a joint agreement, consistent with subsections (J)(1) through (3) of this section. For projects not involving a land division, the city may not issue certificate(s) of occupancy until the property owners have completed subsections (J)(1) through (3) of this section.
1.
Record an easement with the deed allowing cross-access to and from other properties served by the joint-use driveways and cross-access or service drive;
2.
Record an agreement with the deed that remaining access rights along the roadway for the subject property shall be dedicated to the city and pre-existing driveways will be closed and eliminated after construction of the joint-use driveway;
3.
Record a joint maintenance agreement with the deed defining maintenance responsibilities of property owners.
K.
Access Connections and Driveway Design. All openings onto a public right-of-way (access connections) and driveways shall conform to all of the following design standards:
1.
Driveway Approaches. Driveway approaches, including private alleys, shall be designed and located to provide exiting vehicles with an unobstructed view of other vehicles and pedestrians, and to prevent vehicles from backing into the flow of traffic on the public street or causing conflicts with on-site circulation. Construction of driveway accesses along acceleration or deceleration lanes or tapers should be avoided due to the potential for vehicular conflicts. Driveways should be located to allow for safe maneuvering in and around loading areas. See also SDC § 3.3.500, Loading areas.
2.
Access Connections. Access connections shall be the minimum width practicable based on projected traffic volumes and functional requirements. For specific design and construction standards, refer to the public works design standards.
3.
Driveways. Driveways shall meet the following standards, subject to review and approval by the public works director:
a.
Single-Family Dwelling and Duplex Driveways.
i.
Maximum width of 12 feet per off-street parking space, up to a maximum of 32 feet for three or more off-street parking spaces.
ii.
Recreational vehicle pads must be located within the side yard or rear yard to qualify for additional driveway width as an off-street parking space.
iii.
No more than two driveways allowed per lot, with each driveway conforming to the requirements in subsection (K)(1) of this section. Duplexes on a corner lot fronting two local streets are encouraged to provide one driveway per frontage.
iv.
Combined driveways with abutting properties shall not exceed 40 feet in width.
v.
Separate driveways on the same lot must be spaced at least 22 feet apart.
b.
Multiple-Family and Attached Dwelling Driveways.
i.
Each multiple-family unit having separate vehicle access and fronting a different street shall be treated as a single-family dwelling, except that no more than one driveway per unit is allowed.
ii.
Triplexes and fourplexes with off-street parking spaces fronting onto a street shall meet the standards of SDC § 2.2.180.
iii.
Driveways serving multiple-family units with combined access onto a street shall not exceed a width of 32 feet for a single driveway, except where the public works director determines that the width shall be limited to 24 feet, such as in the case of a multifamily development with 10 or fewer dwellings.
c.
Commercial and industrial use driveways shall be the minimum width necessary to efficiently and safely serve the proposed development. The maximum width allowed is 40 feet, except where the public works director determines that a greater width is necessary for traffic operations and safety at street intersections.
d.
Driveway grades should be less than 12 percent. Those grades exceeding 12 percent shall be subject to review and approval by the building official. Grades of 12 percent may not exceed 300 feet in length. The applicant shall provide an engineered plan for any driveway exceeding a grade of 12 percent for review and approval by the building official. Before approval, the building official must determine the driveway does not pose a safety concern.
e.
Driveway cross-slopes shall not exceed two percent, and shall be designed to properly accommodate stormwater runoff.
f.
Driveways 150 feet in length or more shall be provided with a vehicle turnaround meeting the approval of the Silverton fire district.
g.
All driveways must be located the maximum distance which is practical from a street intersection. In no instance shall the distance from an intersection be closer than the following as measured from the near driveway edge, and the through curb line, as shown by the following illustration:
Arterial Street | 250 feet |
Collector Street | 150 feet |
Constrained Collector Street | 50 feet |
Neighborhood/Local Street | 10 feet |
Where streets of different functional classifications intersect, the distance required is that of the classification which requires the greatest distance between the access point and the intersection.
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4.
Driveway Construction. Driveway aprons connecting a driveway to a public street shall be constructed of concrete and installed consistent with the city’s public works design standards. The public works director may require appropriate grade transitions between driveways and abutting sidewalks or walkways to address accessibility requirements. See Figure 3.1.200.K.
Figure 3.1.200.K Typical Driveway Openings with Sidewalks/Walkways  |
L.
Fire Apparatus Access Ways. When required under the Uniform Fire Code, city-approved fire apparatus access ways shall be provided in accordance with city standards.
M.
Vertical Clearances. Driveways, private streets, aisles, turnaround areas and ramps shall have a minimum vertical clearance of 13 feet, six inches for their entire length and width.
N.
Vision Clearance. No visual obstruction (e.g., sign, structure, solid fence, or shrub vegetation) between two feet and eight feet in height shall be placed in “vision clearance areas” on streets, driveways, alleys, or mid-block lanes where no traffic control stop sign or signal is provided, as shown in Figure 3.1.200.N. The sides of the minimum vision clearance triangle are the curb line or, where no curb exists, the edge of pavement. Vision clearance requirements may be modified by the public works director upon finding that more or less sight distance is required (i.e., due to traffic speeds, roadway alignment, etc.). This standard does not apply to light standards, utility poles, tree trunks and similar objects.
Figure 3.1.200.N Vision Clearance Areas (solid lines indicate curbs or edge of pavement)  |
O.
Construction. The following construction standards apply to all driveways:
1.
Surface Options. Driveways, parking areas, aisles, and turnarounds must be paved with asphalt or concrete. Other paving materials may be used, subject to approval by the public works director. For example, porous paving materials such as porous concrete, pavers set in sand, or concrete blocks that allow grass to grow through may be permitted to reduce surface water runoff and protect water quality.
2.
Surface Water Management. All driveways, parking areas, aisles, and turnarounds shall allow on-site collection of surface waters to eliminate sheet flow of such waters onto public rights-of-way and abutting property. Surface water facilities shall be constructed in conformance with the standards contained in the public works design standards. (Single-family dwellings and duplex dwellings exempt.)
3.
Driveway Aprons. When driveway approaches or “aprons” are required to connect driveways to the public right-of-way, they shall be paved with concrete surfacing and conform to the city’s engineering design criteria and standard specifications. (See subsection (K) of this section.)
(Ord. 08-06 § 3, 2008; Ord. 20-09 § 3 (Exh. B), 2020; Ord. 21-04 § 18, 2021)
§ 3.1.300 Pedestrian and bicycle access and circulation.
A.
Site Layout and Design. To ensure safe, direct, and convenient pedestrian circulation, all developments, except single-family detached housing and duplex dwellings, shall provide a continuous pedestrian system. The pedestrian system shall be designed based on the criteria in subsections (A)(1) through (4) of this section:
1.
Continuous Walkway System. The pedestrian walkway system shall extend throughout the development site and connect to all future phases of development, to existing or planned off-site adjacent trails, public parks, and open space areas to the greatest extent practicable, and to adjacent existing or planned transit stops. The developer may also be required to connect or stub walkway(s) to adjacent streets and to private property with a previously reserved public access easement for this purpose in accordance with the provisions of SDC § 3.1.200, Vehicular access and circulation, and SDC § 3.4.100, Transportation standards.
2.
Safe, Direct, and Convenient. Walkways within developments shall provide safe, reasonably direct, and convenient connections between primary building entrances and all adjacent streets, based on the following criteria:
a.
Reasonably Direct. A route that does not deviate unnecessarily from a straight line or a route that does not involve a significant amount of out-of-direction travel for likely users.
b.
Safe and Convenient. Routes that are reasonably free from hazards and provide a reasonably direct route of travel between destinations.
c.
“Primary entrance” for commercial, industrial, mixed use, public, and institutional buildings is the main public entrance to the building. In the case where no public entrance exists, street connections shall be provided to the main employee entrance.
d.
“Primary entrance” for residential buildings is the front door (i.e., facing a street, plaza or courtyard). For multifamily buildings where individual dwelling units do not have their own exterior entrance, the walkway may connect to a lobby, courtyard, or breezeway that serves as a common entrance to multiple dwellings.
3.
Connections within Developments. Connections within developments shall be provided as required in subsections (A)(3)(a) through (c) of this section:
a.
Walkways must connect all building entrances to one another to the extent practicable, as generally shown in Figure 3.1.300.A;
b.
Walkways must connect all on-site parking areas, storage areas, recreational facilities and common areas, and connect off-site adjacent uses to the site to the extent practicable. Topographic or existing development constraints may be cause for not making certain walkway connections; and
Figure 3.1.300.A Pedestrian Pathway System (Typical)  |
 |
c.
Large parking areas shall be broken up so that no contiguous parking area exceeds one acre or 150 parking spaces, whichever is less. Parking areas may be broken up with plazas, landscape areas with pedestrian access ways (20 feet minimum total width), public streets or shopping streets (driveways with street-like features). For the purpose of this section, a “shopping street” means a raised sidewalk of at least four feet in width, six-inch curb, accessible curb ramps, street trees in planter strips or tree wells, and pedestrian-oriented lighting.
4.
Connections from Development. Off-site pedestrian and bicycle facilities that provide connections from the proposed development may be required consistent with findings from a traffic impact study. See SDC § 4.1.900 for traffic impact study requirements.
B.
Walkway Design and Construction. Walkways, including those provided with pedestrian access ways, shall conform to all of the standards in subsections (B)(1) through (4) of this section, as generally illustrated in Figure 3.1.300.B:
Figure 3.1.300.B Pedestrian Walkway Detail (Typical)  |
1.
Vehicle/Walkway Separation. Except for crosswalks (subsection (B)(2) of this section), where a walkway abuts a driveway or street it shall be raised six inches and curbed along the edge of the driveway/street. Alternatively, the decision-making body may approve a walkway abutting a driveway at the same grade as the driveway if the walkway has visually contrasting materials (e.g., pavers or stamped/scored concrete) and is protected from all vehicle maneuvering areas. An example of such protection is a row of decorative metal or concrete bollards designed to withstand a vehicle’s impact, with adequate minimum spacing between them to protect pedestrians.
2.
Crosswalks. Where a walkway crosses a parking area, driveway, or street (“crosswalk”), it shall be clearly marked with painted or thermoplastic striping or similar types of nonpermanent applications. Contrasting paving materials (e.g., stamped or scored concrete or pavers inlaid between asphalt) are permitted. The public works director may require the crosswalk be designed as a raised, speed table-type crossing area.
3.
Walkway Width and Surface. Walkway and access way surfaces shall be concrete, asphalt, brick/masonry pavers, or other durable surface, as approved by the public works director, at least five feet wide. Multi-use paths (i.e., for bicycles and pedestrians) shall be concrete or asphalt and subject to the city of Silverton public works design standards.
4.
Accessible Routes. Walkways shall conform to applicable Americans with Disabilities Act (ADA) guidelines. The ends of all raised walkways, where the walkway intersects a driveway or street, shall provide ramps that are ADA accessible, and walkways shall provide unobstructed, direct routes to primary building entrances.
(Ord. 08-06 § 3, 2008; Ord. 20-09 § 3 (Exh. B), 2020)
§ 3.2.100 Purpose.
The purpose of this chapter is to promote community health, safety, and welfare by protecting natural vegetation and setting development standards for landscaping, street trees, fences, and walls. Together, these elements of the natural and built environment contribute to the visual quality, environmental health, and character of the community. Trees provide climate control through shading during summer months and wind screening during winter. Trees and other plants can also buffer pedestrians from traffic. Walls, fences, trees, and other landscape materials also provide vital screening and buffering between land uses. Landscaped areas help to control surface water drainage and can improve water quality, as compared to paved or built surfaces. This chapter is organized into the following sections:
SDC § 3.2.200, Landscape conservation, prevents the indiscriminate removal of significant trees and other vegetation, including vegetation associated with streams, wetlands, and other protected natural resource areas.
SDC § 3.2.300, Landscaping, sets standards for and requires landscaping of all development sites that require land use review and design review. This section also requires buffering for parking and maneuvering areas, and between different land use districts. Note that other relevant standards are provided in Article 2, Land Use (Zoning) Districts, for specific types of development.
SDC § 3.2.400, Street trees, sets standards for and requires planting of street trees for shading, comfort, water quality, and aesthetic purposes.
SDC § 3.2.500, Fences and walls, regulates the design of fences and walls, including allowable height and materials, to promote security, personal safety, privacy, and aesthetics.
(Ord. 08-06 § 3, 2008)
§ 3.2.200 Landscape conservation.
A.
Applicability. All development sites containing significant vegetation, as defined below, shall comply with the standards of this section and be subject to development review. The purpose of this section is to incorporate significant native vegetation into the landscapes of development and to protect vegetation in sensitive natural areas. The use of mature, native vegetation within developments is a preferred alternative to removal of vegetation and replanting. Mature landscaping provides summer shade and wind breaks, controls erosion, and allows for water conservation due to larger plants having established root systems. Refer to Chapter 3.6 SDC for additional tree requirements.
B.
Significant Vegetation. “Significant vegetation” means trees and plants within designated sensitive land areas such as floodplains, hillside protection areas, and wetlands. Protection shall not be required for nonnative, invasive plants (blackberries, poison oak, poison ivy, etc.) and any plants designated by the city as prohibited.
C.
Mapping and Protection Required. Significant vegetation shall be mapped as required by Chapter 4.2 SDC, Land Use Review and Design Review. Significant trees shall be mapped and protected per Chapter 3.6 SDC, Trees. The city also may require an assessment prepared by an arborist or other qualified professional to determine recommended protection or mitigation requirements.
D.
Protection Standards. Trees on public lands shall not be removed, cut, felled, trimmed or otherwise damaged or destroyed, except as approved by the city. The city may approve removal or trimming when a tree poses an immediate hazard to public safety as determined by the public works director. Trees on private land shall follow provisions of Chapter 3.6 SDC.
E.
Mitigation Required. Where removal of or impact to significant vegetation is proposed, or it is reasonable to expect it will be unavoidable during development, the city shall require mitigation through development review. Mitigation shall be proportionate to the loss of significant vegetation. Where complete mitigation on site is not practical due to limitations of the site, the city may accept an in-lieu fee for mitigation which will occur off site.
F.
Construction. All significant vegetation on a site that is not otherwise designated and approved by the city for removal shall be protected prior to, during, and after construction in accordance with a limit-of-clearing and grading plan approved by the planning official. The city may require chain-link or other protective fencing around significant vegetation and limit grading activities and operation of vehicles and heavy equipment in and around significant vegetation areas to prevent damage to the resource and to prevent erosion, pollution, or landslide hazards.
G.
Tree Felling. Review approval is required for the felling of five or more trees that have a caliper of six inches or larger at four and a half feet above grade on a lot or property inside the city limits within a calendar year. Felling trees at the direction of the city or by the city necessary to remove or alleviate an immediate danger to life or property; removal of any tree that is defined as a nuisance under the Silverton Municipal Code; to restore utility service or to reopen or maintain a public street or easement is exempt from review.
H.
Exemptions. The protection standards in subsections (D) and (E) of this section do not apply to:
1.
Dead or Diseased Vegetation. Dead or diseased vegetation meeting the criteria for “significant vegetation” may be removed after approval of a Type I land use review.
2.
Hazardous Vegetation and Other Emergencies. Significant vegetation may be removed without land use approval when the vegetation poses an immediate threat to life or safety or protection of property (e.g., windstorm damage, fallen-over house, road or power line, blocked drainage way, or similar circumstance).
(Ord. 08-06 § 3, 2008; Ord. 25-09 § 3, 2025)
§ 3.2.300 Landscaping.
A.
Applicability. This section shall apply to all new developments requiring land use review and design review.
B.
Landscaping Plan Required. A landscape plan is required. All landscape plans shall conform to the requirements in SDC § 4.2.500(B)(5). See Chapter 3.6 SDC for tree submittal requirements.
C.
Landscape Area Standards. Landscape areas shall be as provided in the base zone (Article 2) and other applicable provisions of this code (e.g., parking areas, buffering, screening, street trees, etc.).
D.
Landscape Materials. Permitted landscape materials include trees, shrubs, ground cover plants, nonplant ground covers, and outdoor hardscape features, as described below. “Coverage” is based on the projected size of the plants at maturity, i.e., typically three years after planting.
1.
Existing Vegetation. Existing noninvasive vegetation may be used in meeting landscape requirements.
2.
Plant Selection. A combination of deciduous and evergreen trees, shrubs, and ground covers shall be used for all planted areas, the selection of which shall be based on local climate, exposure, water availability, and drainage conditions. When new vegetation is planted, soils shall be amended, as necessary, to allow for healthy plant growth.
3.
“Nonnative, invasive” plants, as per SDC § 3.2.200(B), shall be removed during site development and the planting of new invasive species is prohibited.
4.
Hardscape features, such as plazas, pathways, patios and other pedestrian amenities may count toward 10 percent of the required landscape area, except in the commercial districts, where hardscape features may count toward 50 percent of the landscape area; provided, that such features conform to SDC § 2.3.170. Street trees, where required, do not count toward the minimum landscape area. Swimming pools, sports courts, decks and similar facilities may not be counted toward fulfilling the landscape requirement in any zone.
5.
Ground Cover Standard. All landscaped areas, whether or not required, that are not planted with trees and shrubs, or covered with nonplant material (subsection (D)(8) of this section), shall have ground cover plants that are sized and spaced with a minimum of one plant per 12 inches on center in triangular spacing, or other planting pattern that is designed to achieve 50 percent or greater coverage of all areas not covered by shrubs or trees.
6.
Tree Size. Trees shall have a minimum caliper of two inches or greater at time of planting.
7.
Shrub Size. Shrubs shall be planted from five-gallon containers or larger.
8.
Nonplant Ground Covers. Bark dust, chips, aggregate, or other nonplant ground covers may be used, but shall cover no more than 50 percent of the area to be landscaped and shall be confined to areas underneath plants. Nonplant ground covers cannot be a substitute for ground cover plants.
9.
Significant Vegetation. Significant vegetation protected in accordance with SDC § 3.2.200 may be credited toward meeting the minimum landscape area standards.
10.
Stormwater Facilities. Stormwater facilities (e.g., detention/retention ponds and swales designed for water quality treatment), when allowed, shall be landscaped with water-tolerant, native plants.
E.
Landscape Design Standards. All yards, parking lots, and required street tree planter strips shall be landscaped to provide, as applicable, erosion control, visual interest, buffering, privacy, open space and pathway identification, shading, and wind buffering, based on the following criteria and standards:
1.
Yard Setback Landscaping Design. Landscaping in yards shall:
a.
Provide visual screening and privacy within side and rear yards; while leaving front yards and building entrances mostly visible for security purposes.
b.
Use shrubs and trees as wind breaks and to screen parking areas.
c.
Retain natural vegetation.
d.
Define pedestrian pathways and open space areas with landscape materials.
e.
Provide focal points within a development, for example, by preserving large or unique trees or groves, hedges, and flowering plants.
f.
Use trees to provide summer shading within common open space areas and within front yards when street trees cannot be provided.
g.
Use a combination of plants for year-long color and interest.
h.
Use landscaping to screen outdoor storage and mechanical equipment areas, and to enhance graded areas such as berms, swales, and detention/retention ponds.
2.
Yard Setback Landscaping Requirements. Landscaping requirements listed by type of use:
a.
Residential, Single-Family. All front yards (exclusive of access ways and other permitted intrusions) are required to be landscaped with one tree at least six feet in height (two-inch minimum caliper) and two five-gallon shrubs or accent plants per 1,000 square feet of required yard area with the remaining area to be treated with an attractive ground cover (e.g., lawn, bark, rock, ivy, evergreen shrubs) within six months of issuance of an occupancy permit.
b.
Commercial and Multifamily. All required yards adjacent to a street (exclusive of access ways and other permitted intrusions) are required to be landscaped with one tree at least six feet in height (two-inch minimum caliper) and five five-gallon shrubs or accent plants per 1,000 square feet of required yard area with the remaining area to be treated with an attractive ground cover (e.g., lawn, bark, rock, ivy, evergreen shrubs) prior to issuance of an occupancy permit.
c.
Industrial and Public/Semi-Public. All required yards adjacent to a street (exclusive of access ways and other permitted intrusions) are required to be landscaped with one tree at least six feet in height (two-inch minimum caliper) and five-gallon shrubs or accent plants per 1,000 square feet of required yard area, with the remaining area to be treated with an attractive ground cover (e.g., lawn, bark, rock, ivy, and evergreen shrubs) prior to issuance of an occupancy permit. Where the yard adjacent to a street of an industrially or publicly/semi-publicly zoned property is across a right-of-way from other industrially, commercially, or publicly/semi-publicly zoned property, only 30 percent of such yard area must be landscaped.
3.
Parking Areas. A minimum 10 percent of the total surface area of all parking areas, as measured around the perimeter of all parking spaces and maneuvering areas, shall be landscaped. Such landscaping shall consist of “evenly distributed” shade trees with shrubs and/or ground cover plants that conform to the criteria in subsections (E)(1)(a) through (h) of this section. “Evenly distributed” means that the trees and other plants are distributed around the parking lot perimeter and between parking bays to provide a partial canopy. At a minimum, one tree per 10 parking spaces on average shall be planted to create a partial tree canopy over and around the parking area. Parking areas shall include landscape islands with trees to break up the parking area into rows of not more than 10 contiguous (side-by-side) parking spaces. All parking area landscapes shall have dimensions of not less than 24 square feet of area, or not less than four feet in width by six feet in length, to ensure adequate soil, water, and space for healthy plant growth. Such areas shall have irrigation or temporary irrigation to ensure plant survival and success.
Figure 3.2.300(E)(1) General Landscape Areas (Typical)  |
4.
Screening and Buffering Required. Screening and buffering are required under the following conditions:
a.
Parking/Maneuvering Area Adjacent to Streets and Drives. Where a parking or maneuvering area is adjacent and parallel to a street or driveway, an evergreen hedge, decorative wall (masonry or similar quality material) with openings, arcade, trellis, or similar partially opaque structure six feet in height shall be established between street and driveway. The required screening shall have breaks to allow visibility (natural surveillance) into the site and to allow pedestrian access to any adjoining walkways. Hedges used to comply with this standard shall be a minimum of 36 inches in height at maturity, and shall be of such species, number, and spacing as to provide year-round screening within one year after planting. Vegetative ground cover is required on all surfaces between the wall/hedge and the street/driveway line.
b.
Parking/Maneuvering Area Adjacent to Building. Where a parking or maneuvering area or driveway is adjacent to a building, the area shall be separated from the building by a curb and a raised walkway, plaza, or landscaped buffer not less than five feet in width and six feet in height. Raised curbs, bollards, wheel stops, or other design features shall be used to protect pedestrians, landscaping, and buildings from being damaged by vehicles. Where parking areas are located adjacent to residential ground-floor living space, a four-foot-wide landscape buffer with a curbed edge may fulfill this requirement.
c.
Screening of Mechanical Equipment, Outdoor Storage, Service and Delivery Areas, and Other Screening When Required. All mechanical equipment, outdoor storage and manufacturing, and service and delivery areas shall be screened from view from all public streets and adjacent residential districts. When these or other areas are required to be screened, such screening shall be provided by:
i.
A decorative wall (i.e., masonry or similar quality material);
ii.
An evergreen hedge;
iii.
An opaque or sight-obscuring fence complying with SDC § 3.2.500; or
iv.
A similar feature accepted by the approval authority providing an adequate screen.
Walls, fences, and hedges shall comply with the vision clearance requirements and provide for pedestrian circulation, in accordance with Chapter 3.1 SDC, Access and Circulation. (See SDC § 3.2.500 for standards specific to fences and walls.)
d.
Existing Significant Vegetation. Where significant vegetation exists it shall be preserved as a “buffer” around the development/subdivision within the setback areas at a minimum. The reviewing body may require preservation of other tree groves and clusters of significant vegetation through design review or the planned development process when an applicant has requested an adjustment to code standards, as provided under Chapters 4.2 and 4.5 SDC.
e.
Between Different Land Uses. Perimeter screening and buffering requirements of Table 3.2.300(E)(2), Table 3.2.300(E)(3) and Figure 3.2.300(E)(4) are in addition to standard setbacks of the applicable zoning district and the yard setback landscaping requirements of subsection (E)(2) of this section. Perimeter screening and buffering shall be located as near to the property line as possible. In a case of two overlapping screening and buffering types, the higher type shall prevail. To determine the type of perimeter screening and buffering required, the following procedures shall be used:
i.
Identify the subject property’s zoning district. Identify the adjacent property(ies) zoning district(s) and determine if the property(ies) is developed or vacant.
ii.
Determine the perimeter screening and buffering type by referring to Table 3.2.300(E)(2).
iii.
Determine the perimeter screening and buffering type standards by referring to Table 3.2.300(E)(3). For the landscaping requirements, all plant units shall be rounded up and existing vegetation may be used to satisfy planting requirements.
iv.
Determine the perimeter screening and buffering structures by referring to Figure 3.2.300(E)(4).
v.
Screening and buffering requirements for developments adjacent to the city limits or urban growth boundary shall be determined by the community development director or designee.
vi.
When the subject property develops prior to an adjacent vacant property, the vacant perimeter screening and buffering type shall be used. When the adjacent vacant property develops, all remaining screening and buffering requirements of Table 3.2.300(E)(2) shall be installed between the two developed uses.
vii.
The perimeter screening and buffering standards of this section are not required when properties are separated by a public street.
viii.
When different land uses are developed with a planned development, screening and buffering standards between those uses shall be similar to Table 3.2.300(E)(2), as determined by the community development director or designee.
Perimeter Screening and Buffering Types Table 3.2.300(E)(2) | |||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|
ADJACENT LAND USE DISTRICT | |||||||||||
DEVELOPED | VACANT | ||||||||||
R-1 AR | R-5 | RM-10 RM-20 DCF | DC GC P | IP LI I | R-1 AR | R-5 | RM-10 RM-20 DCF | DC GC P | IP LI I | ||
SUBJECT PROPERTY LAND USE DISTRICT | R-1 AR | 0 | 1 | 2 | 3 | 4 | 0 | 1 | 2 | 3 | 3 |
R-5 | 1 | 0 | 2 | 3 | 4 | 1 | 0 | 3 | 3 | 3 | |
RM-10 RM-20 DCF | 2 | 2 | 0 | 3 | 4 | 2 | 2 | 0 | 3 | 3 | |
DC GC P | 3 | 3 | 3 | 0 | 3 | 3 | 3 | 3 | 0 | 3 | |
IP LI I | 4 | 4 | 4 | 3 | 0 | 4 | 4 | 4 | 3 | 0 | |
Perimeter Screening and Buffering Standards Table 3.2.300(E)(3) | ||||
|---|---|---|---|---|
SCREENING AND BUFFERING TYPE | PLANT UNITS PER 100 LINEAL FEET | ADDITIONAL SETBACK OPTIONS (IN FEET) | PLANT UNIT MULTIPLIER | STRUCTURE REQUIRED (TABLE 3.2.300(E)(3)) |
1 | 2 Canopy Trees 2 Understory Trees | 5.0 7.5 10.0 12.5 | 1.0 0.8 0.6 0.4 | F-1 F-1 None None |
2 | 2 Canopy Trees 4 Understory Trees | 5.0 7.5 10.0 12.5 | 1.0 0.8 0.6 0.4 | F-2 F-2 F-2 F-2 |
3 | 5 Canopy Trees 10 Understory Trees 15 Shrubs | 10.0 15.0 20.0 25.0 | 0.9 1.0 0.8 0.6 | BW-1 BW-1 F-3 F-3 |
4 | 6 Canopy Trees 9 Understory Trees 36 Shrubs 18 Evergreen Trees | 20.0 30.0 40.0 50.0 | 0.6 0.8 1.0 0.8 | BW-2 BW-2 BW-1 BW-1 |
 Perimeter Screening and Buffering Structures Figure 3.2.300(E)(4) |
F.
Irrigation. All required landscape areas except for single-family dwellings, duplexes and triplexes shall be provided with a piped under-ground water supply irrigation unless a licensed landscape architect or certified nurseryman submits written verification that the proposed plant materials do not require irrigation. Irrigation systems installed in the public right-of-way require an encroachment permit. The use of indigenous drought-tolerant plants from the city’s approved plant list is encouraged, and may be required where exposure, slope or soil conditions warrant. Irrigation shall be provided for plants that are not drought-tolerant.
G.
Maintenance. If the plantings fail to survive within three years, the property owner shall replace them with an equivalent specimen (i.e., evergreen shrub replaces evergreen shrub, deciduous tree replaces deciduous tree, etc.) within six months of their dying or removal, whichever comes first. All manmade features required by this code shall be maintained in good condition, or otherwise replaced by the owner within six months of any such feature being removed or irreversibly damaged (whichever comes first).
1.
Height Requirements. Trees or shrubs growing in the right-of-way or on private property must be trimmed to maintain a minimum canopy height of eight feet above sidewalks, or 12 feet above streets or alleys.
2.
Trimming – Specifications – Owner Responsibility.
a.
Trees, shrubs or plants standing in or upon any public street or alley, or on private grounds, and having branches projecting into the public street or sidewalk, shall be kept trimmed by the owner or owners of the property adjacent to or in front of such trees, shrubs or plants, growing so that:
i.
The lowest branches shall not be less than a minimum of 12 feet above any surface of the street pavement, and shall not be less than 14 feet above the surface of streets designated as state highways;
ii.
The lowest branches shall not be less than a minimum of eight feet above any surface of a sidewalk;
iii.
The highest branches of any bush or shrub on private property shall comply with the clear vision area requirements.
b.
Newly planted trees may remain untrimmed; provided, that they do not interfere with street traffic or persons using the sidewalk, or obstruct the light of any street electric lamp.
3.
Trimming – Notice to Comply. Whenever the owner or owners, lessees, occupants or persons in charge of private grounds neglect or refuse to trim any tree, shrub or plant, as provided in this code, the city shall serve upon such owner or owners, lessees, occupants or persons in charge a written notice to trim such tree or trees, shrubs or plants within 10 days after giving of such notice; failure to do so will be considered in violation of this chapter and subject to the penalties provided in this code. Such notice shall be served upon the owner or owners, lessees, occupants, person in charge, or occupant of the property by posting the same upon such property or near to the trees, shrubs or plants to be trimmed.
4.
Trimming – City to Perform Work When. If the owner or owners, lessees, occupants or persons in charge of the property fail and neglect to trim such trees, shrubs or plants within 10 days after receiving said notice, the city manager or duly authorized representative may cause any vegetation in or upon any parking strip, street right-of-way or other public place in the city to be trimmed, pruned, or removed.
5.
Removal of Trees or Shrubs.
a.
The city manager may remove or cause or order to be removed any tree, plant or shrubs, or part thereof, planted or growing in or upon any public street or alley which is in unsafe conditions, which by reason of its nature is injurious to sewers or other public improvements, or is affected with an injurious fungal disease, insect or other pest.
b.
Whenever, in the opinion of the city manager, trimming or treatment of any such tree or shrub located on private ground but have branches extending over any public street or alley is deemed necessary, the city manager shall have the power to trim or treat any such branch or branches, or cause or order the same to be trimmed or treated.
(Ord. 08-06 § 3, 2008; Ord. 10-02 Exh. A § B, 2010; Ord. 25-09 § 3, 2025)
§ 3.2.400 Street trees.
Street trees shall be planted in all new subdivisions and any project classified as a major project, except where specifically exempt under this code or where the reviewing body approves an adjustment to the street design standards under SDC § 3.4.100, Transportation standards. Planting of street trees shall generally follow construction of curbs and sidewalks; however, the city may defer tree planting until final inspection of completed dwellings to avoid damage to trees during construction. The planting and maintenance of street trees shall conform to the following standards and guidelines and any applicable road authority requirements:
A.
Growth Characteristics. Trees shall be selected based on climate zone, growth characteristics and site conditions, including available space, overhead clearance, soil conditions, exposure, and desired color and appearance. Drought-resistant trees should be chosen where they suit the specific soil type.
B.
Caliper Size. The minimum caliper size at planting is two inches.
C.
Spacing and Location. The intent of this section is to provide a procession of trees for shade, buffering, pedestrian comfort and aesthetics on all city streets. Street trees shall be spaced so that there is at least one tree planted for every 35 feet of street frontage, except where existing utilities, vision clearance requirements or similar factors preclude such spacing. Actual spacing of trees may vary based on the growth habits of selected trees. See the city of Silverton street tree and tree crown area reference list in SDC § 3.6.170.
D.
Soil Preparation, Planting and Care. The developer shall be responsible for planting street trees, including soil preparation, ground cover material, staking, and temporary irrigation for one year after planting. The developer shall also be responsible for tree care (pruning, watering, fertilization, and replacement as necessary) during the first two years after planting, after which the adjacent property owners shall maintain the trees.
E.
Assurances. The city shall require the developer to provide a performance and maintenance bond or cash deposit in an amount determined by an estimate provided by the developer or by the community development director, to ensure the planting of the tree(s) and care during the first year after planting.
F.
Street Tree List. A list of approved street trees is available at Silverton City Hall.
(Ord. 08-06 § 3, 2008; Ord. 09-25 § 3, 2025)
§ 3.2.500 Fences and walls.
Construction of fences and walls shall conform to all of the following requirements:
A.
General Requirements. All fences, walls, or hedges shall comply with the height limitations of the respective zoning district (Article 2, Tables 2.2.120.A and 2.3.120) and the standards of this section. The city may require installation of walls and/or fences as a condition of development approval, in accordance with land division approval (e.g., flag lots), approval of a conditional use, or design review approval. A building permit is required for fences greater than six feet in height (see also SDC § 3.2.300 for landscape screening wall requirements). All fences shall be located outside any vision clearance area.
B.
Dimensions.
1.
The combined height of fences and/or retaining walls and/or other decorative landscape elements (i.e., rocks, railroad ties, etc.) within a front yard setback or in front of the front facade of a building shall not exceed 42 inches as measured from the grade closest to the street right-of-way. Fences in the front yard of corner lots may be six feet in height, provided the fence is 50 feet from the through-curb intersection and set back at least five feet from the property line.
 |
2.
Fences built atop retaining walls shall conform to the following standards:
a.
When the retaining wall is not adjacent to or abutting a public right-of-way and is less than 30 inches in height from finished grade, the maximum height of the fence shall be six feet in a residential zoning district and eight feet in a commercial or industrial zoning district.
b.
When the retaining wall is not adjacent to or abutting a public right-of-way and is greater than 30 inches in height from finished grade, the combined height of the wall and fence from finished grade shall not exceed eight and one-half feet in a residential zoning district and 10 feet in a commercial or industrial zoning district.
c.
Fences located on top of retaining walls greater than 30 inches in height from finished grade and not adjacent to or abutting a public right-of-way may exceed the total allowed combined height listed in subsection (B)(2)(b) of this section; provided, that the fence is located a minimum of two feet from the retaining wall and the fence height does not exceed six feet in height with a maximum combined height of 15 feet (the maximum height requirement does not apply to any safety measure required by the International Building Code).
3.
One arbor, gate, or similar garden structures not exceeding eight feet in height and six feet in width is allowed per yard; provided, that it is not within a required clear vision area.
4.
Walls and fences to be built for required buffers shall comply with SDC § 3.2.300.
5.
Fences and walls shall comply with the vision clearance standards of SDC § 3.1.200.
C.
Maintenance. For safety and for compliance with the purpose of this chapter, walls and fences required as a condition of development approval shall be maintained in good condition, or otherwise replaced by the property owner.
D.
Materials.
1.
Permitted materials: wood, chain-link steel, iron, bricks, stone, rusticated concrete masonry block, stucco, or similar masonry, and nonprohibited evergreen plants are permitted. Poured concrete walls must be striated, battered, scored or have other finished surface. Materials on all projects other than single-family and duplex dwellings on individual lots are subject to review and approval through design review.
2.
Prohibited materials: unfinished concrete blocks, straw bales, barbed or razor wire, scrap lumber or other scrap materials, sheet metal, hedges taller than eight feet and similar fence and wall materials are prohibited. Electric fences are also prohibited.
3.
Masonry walls exceeding four feet in height are subject to review and approval by the building official. Fences and walls taller than six feet are subject to landscape screening and require a building permit.
 |
(Ord. 08-06 § 3, 2008; Ord. 10-02 Exh. A § B, 2010)
§ 3.3.100 Purpose.
The purpose of this chapter is to provide basic and flexible standards for development of vehicle and bicycle parking. The design of parking areas is critically important to the economic viability of some commercial areas, pedestrian and driver safety, the efficient and safe operation of adjoining streets, and community image and livability. Historically, some communities have required more parking than is necessary for some land uses, paving extensive areas of land that could be put to better use. Because vehicle parking facilities occupy large amounts of land, they must be planned and designed carefully to use the land efficiently, minimize stormwater runoff, and maintain the visual character of the community. This chapter recognizes that each development has unique parking needs and provides a flexible approach for determining parking space requirements (i.e., “minimum” and “performance-based” standards). This chapter also provides standards for bicycle parking because many people use bicycles for recreation, commuting, and general transportation. Children as well as adults need safe and adequate spaces to park their bicycles throughout the community.
(Ord. 08-06 § 3, 2008)
§ 3.3.200 Applicability.
All developments subject to land use review or design review (Chapter 4.2 SDC), including modifications to existing parking facilities, must comply with the provisions of this chapter.
(Ord. 08-06 § 3, 2008)
§ 3.3.300 Automobile parking standards.
A.
Vehicle Parking – Minimum Standards by Use. The number of required off-street vehicle parking spaces is determined in accordance with the standards in Table 3.3.300.A or, alternatively, through a separate parking demand analysis as described in subsection (A)(2) of this section.
1.
Where a use is not specifically listed in this table, parking requirements are determined by finding that a use is similar to one of those listed in terms of parking needs, or by estimating parking needs individually using the demand analysis option described below.
2.
An applicant may propose parking in amounts less than listed in Table 3.3.300.A by submitting a parking demand analysis to the community development director for review and approval. The parking demand analyses must be based on the proposed use and provide an estimate of parking demand based on the number of employees and customers/visitors who are likely to travel to the subject site by automobile, transit, bicycle and foot. The analysis is reviewed through a Type II land use review, or a Type III review if the request is part of an application that is already subject to Type III review. The reviewing body may approve, approve with conditions or deny the proposal.
3.
Parking that counts toward the minimum requirement is parking in garages, carports, parking lots, bays along driveways, shared parking, and designated on-street parking when approved through land use review or design review, as applicable, and subject to subsection (C) of this section. In recognition that downtown is the most compact and walkable area of Silverton, off-street parking requirements are waived in the downtown commercial (DC) district.
Table 3.3.300.A – Minimum Required Parking by Use | |
|---|---|
Use Categories (Examples of uses are in Chapter 1.6 SDC; definitions are in Chapter 1.5 SDC.) | Minimum Parking per Land Use (fractions rounded down to the closest whole number) |
Residential Categories | |
Household Living | |
Accessory dwelling | None |
Single-family dwelling, including attached and detached dwellings and manufactured homes | 2 spaces per dwelling unit provided on-street parking is available. If on-street parking is not available, then each unit must provide 3 spaces. |
Duplex | 1 space per dwelling unit (2 per duplex) |
Multifamily | 1 space per studio or 1-bedroom unit plus 1 visitor space for each 4 units 1.5 spaces per 2-bedroom unit plus 1 visitor space for each 4 units 2.25 spaces per 3-bedroom or larger unit plus 1 visitor space for each 4 units |
Group living, such as nursing or convalescent homes, rest homes, assisted living, congregate care, and similar special needs housing | 1 space per 4 bedrooms plus 1 space per employee based on the largest shift |
Commercial Categories | |
Drive-up/drive-in/drive-through facilities (drive-up windows, kiosks, ATMs, similar uses/facilities), per SDC § 2.3.160 | No parking requirement if drive-up/drive-in/drive-through is in conjunction with a business. If not in conjunction with a business, then one space per employee is required. See SDC § 2.3.160 for queuing area requirements |
Bed and breakfast inn | 1 space per rentable bedroom plus 1 space for owner/manager |
Educational services, not a school (e.g., tutoring or similar services) | 1 space per 500 sq. ft. floor area |
Entertainment, major event | 1 space for every 4 event attendees plus 1 space for every 3 employees |
Offices | 1 space per 400 sq. ft. of floor area |
Outdoor recreation, commercial | 1 space for every 4 event attendees plus 1 space for every 3 employees |
Parking lot (when not an accessory use) | None |
Quick vehicle servicing or vehicle repair. (See also drive-up/drive-in/drive-through uses, per SDC § 2.3.160) | 2 spaces per service bay plus 1 per employee |
Retail sales and service (See also drive-up uses) | Retail: 1 space per 400 sq. ft., plus 1 space for each 3 employees except bulk retail (e.g., auto, boat, trailers, nurseries, lumber and construction materials, furniture, appliances, and similar sales) 1 per 1,000 sq. ft. Restaurants and Bars: 8 spaces per 1,000 sq. ft. floor area Health Clubs, Gyms: 1 space per piece of workout equipment or workout station; plus one space for every 3 employees Continuous Entertainment (e.g., bowling alleys): 1 space for every 4 patrons or 1 space per bowling lane plus 1 space for every 3 employees Lodging (hotels, motels, inns), (see also bed and breakfast inns): 1 space per rentable room plus 1 space for every 3 employees. For associated uses, such as restaurants, entertainment uses, and bars, see above Theaters and Cinemas: 1 space per every 4 seats |
Self-service storage | 2 spaces |
Industrial Categories | |
Industrial service (See also drive-up uses) | A minimum of 2 spaces; 1 space per 1,000 sq. ft. of floor area |
Manufacturing and production | A minimum of 2 spaces; 1 space per 1,000 sq. ft. of floor area |
Warehouse and freight movement | A minimum of 2 spaces; 1 space per 1,000 sq. ft. of floor area |
Wholesale Sales | |
- Fully enclosed | 1 space per 1,000 sq. ft.: A minimum of 2 spaces |
- Not enclosed | 1 space per 1,000 sq. ft.: A minimum of 2 spaces |
Institutional Categories | |
Basic utilities | None |
Community service | 1 space per 200 sq. ft. of floor area |
Daycare, adult or child daycare; does not include family daycare (12 or fewer children) under ORS 657A.250 | 1 drop-off space for every 10 children plus 1 space for each employee |
Parks and open space | 1 space for every 4 attendees or per CU review (Chapter 4.4 SDC) for active recreation areas |
Religious institutions and houses of worship | 1 space per every 4 seats of the main assembly area; or per CU review, as applicable |
Schools | Grade, elementary, middle, junior high schools: 2 spaces per classroom High schools: 1 space per 6 students plus 1 space per full-time employee |
Other Categories | |
Accessory uses (with a permitted use) | No standard, except some uses may be required to provide parking under the minimum standards for primary uses, as determined by the decision body through land use review, conditional use review, or site design review |
Agriculture – Nurseries and similar horticulture | See retail sales and wholesale, as applicable |
Radio frequency transmission facilities | None |
Rail lines and utility corridors, except those existing prior to effective date of the ordinance codified in this title. | None |
Temporary uses (limited to “P” and “CU” uses), per SDC § 4.9.100. | As determined per SDC § 4.9.100 |
Transportation facilities (operation, maintenance, preservation, and construction in accordance with the city’s transportation system plan) | None |
B.
Vehicle Parking – Minimum Accessible Parking.
1.
Accessible parking shall be provided for all uses in accordance with the standards in Table 3.3.300.B; parking spaces used to meet the standards in Table 3.3.300.B shall be counted toward meeting off-street parking requirements in Table 3.3.300.A;
2.
Such parking shall be located in close proximity to building entrances and shall be designed to permit occupants of vehicles to reach the entrance on an unobstructed path or walkway;
3.
Accessible spaces shall be grouped in pairs where possible;
4.
Where covered parking is provided, covered accessible spaces shall be provided in the same ratio as covered nonaccessible spaces;
5.
Required accessible parking spaces shall be identified with signs and pavement markings identifying them as reserved for persons with disabilities; signs shall be posted directly in front of the parking space at a height of no less than 42 inches and no more than 72 inches above pavement level. Van spaces shall be specifically identified as such.
Table 3.3.300.B – Minimum Number of Accessible Parking Spaces Source: ADA Standards for Accessible Design 4.1.2(5) | |||
|---|---|---|---|
Total Number of Parking Spaces Provided (per lot) | Total Minimum Number of Accessible Parking Spaces (with 60-inch access aisle, or 96-inch aisle for vans*) | Van Accessible Parking Spaces (with min. 96-inchwide access aisle) | Accessible Parking Spaces (with min. 60-inch wide access aisle) |
Column A | |||
1 to 25 | 1 | 1 | 0 |
26 to 50 | 2 | 1 | 1 |
51 to 75 | 3 | 1 | 2 |
76 to 100 | 4 | 1 | 3 |
101 to 150 | 5 | 1 | 4 |
151 to 200 | 6 | 1 | 5 |
201 to 300 | 7 | 1 | 6 |
301 to 400 | 8 | 1 | 7 |
401 to 500 | 9 | 2 | 7 |
501 to 1,000 | 2% of total parking provided in each lot | 1/8 of Column A** | 7/8 of Column A*** |
1,001 | 20 plus 1 for each 100 over 1,000 | 1/8 of Column A** | 7/8 of Column A*** |
Notes: |
|---|
*vans and cars may share access aisles |
**one out of every eight accessible spaces |
***seven out of every eight accessible parking spaces |
C.
On-Street Parking. On-street parking shall conform to the following standards:
1.
Dimensions. The following constitutes one on-street parking space:
a.
Parallel parking, each 22 feet of uninterrupted curb;
b.
Diagonal (45- to 60-degree) parking, each with 12 feet of curb;
c.
Ninety-degree (perpendicular) parking, each with nine feet of curb.
2.
Location. When approved through land use review or design review, as applicable, on-street parking may be counted toward the minimum standards in Table 3.3.300.A when it is on the block face abutting the subject site. An on-street parking space must not obstruct a required clear vision area and it must not violate any law or street standard.
3.
Public Use Required for Credit. On-street parking spaces counted toward meeting the parking requirements of a specific use may not be used exclusively by that use, but shall be available for general public use at all times. Signs or other actions that limit general public use of on-street spaces are prohibited.
D.
Shared Parking. Required parking facilities for two or more uses, structures, or parcels of land may be satisfied by the same parking facilities used jointly, to the extent that the owners or operators show that the need for parking facilities does not materially overlap (e.g., uses primarily of a day-time versus nighttime nature; weekday uses versus weekend uses); and provided, that the right of joint use is evidenced by a recorded deed, lease, contract, or similar written instrument establishing the joint use. The city may approve owner requests for shared parking through land use review or design review, as applicable.
E.
Off-Site Parking. Except for single-family dwellings and duplexes, the vehicle parking spaces required by this chapter may be located on another parcel of land, provided the parcel is within 500 feet of the use it serves and the city has approved the off-site parking through land use review or design review, as applicable. The distance from the parking area to the use shall be measured from the nearest parking space to a building entrance, following a sidewalk or other pedestrian route. The right to use the off-site parking must be evidenced by a recorded deed, lease, easement, or similar written instrument.
F.
General Parking Standards.
1.
Location. Parking is allowed only on streets, within garages, carports, and other structures, or on driveways or parking lots that have been designed and developed in conformance with this code. Article 2, Land Use (Zoning) Districts, prescribes parking location for some land uses (e.g., the requirement that parking for some multiple-family and commercial developments be located to the side or rear of buildings), and Chapter 3.1 SDC, Access and Circulation, provides design standards for driveways. Street parking spaces shall not include space in a vehicle travel lane (including emergency or fire access lanes), public right-of-way, pedestrian access way, landscape, or other undesignated area.
2.
Mixed Uses. If more than one type of land use occupies a single structure or parcel of land, the total requirements for off-street automobile parking shall be the sum of the requirements for all uses, unless it can be shown that the peak parking demands are less (i.e., the uses operate on different days or at different times of the day). The city may reduce the total parking required accordingly through land use review or design review, as applicable.
3.
Availability of Facilities. Owners of off-street parking facilities may post a sign indicating that such off-street parking, or portions thereof, is available only for residents, customers, and/or employees.
4.
Lighting. Parking areas shall have lighting to provide not less than two footcandles of illumination over walkways leading to and from parking area. Similar lighting should be provided over parking areas but complete illumination of parking spaces at two footcandles is not required. Light standards shall be directed downward only and shielded to prevent lighting spillover into any adjacent residential district or use and to prevent light pollution in the night sky.
5.
Screening of Parking Areas. Parking spaces shall be located or screened so that head-lights do not shine onto adjacent residential uses, per subsection (E) of this section.
6.
Carpool/Vanpool/Rideshare Parking. Parking areas that have designated employee parking and more than 20 vehicle parking spaces shall provide at least 10 percent of the employee parking spaces (minimum two spaces) as preferential carpool, vanpool, and rideshare parking spaces. Preferential carpool, vanpool, and rideshare parking spaces shall be closer to the employee entrance of the building than other parking spaces, with the exception of ADA accessible parking spaces.
7.
Transit-Related Facilities in Parking Areas. Parking spaces and portions of parking areas may be used for transit-related uses such as transit stops and park-and-ride or rideshare areas, provided the improvements are identified in an adopted transit or transportation plan and applicable requirements in this section can still be met.
G.
Parking Stall Design and Minimum Dimensions. All off-street parking spaces shall be improved to conform to city standards for surfacing, stormwater management, and striping. Standard parking spaces shall conform to the following standards and the dimensions in Figures 3.3.300.F(1) and (2), and Table 3.3.300.F:
1.
Motor vehicle parking spaces shall measure nine feet wide by 18 feet long or by 16 feet long, with not more than a two-foot overhang when allowed;
2.
All parallel motor vehicle parking spaces shall measure eight feet wide by 22 feet;
3.
Parking area layout shall conform to the dimensions in Figures 3.3.300.F(1) and (2), and Table 3.3.300.F in this section;
4.
Not more than 20 percent of the total parking spaces in a parking lot may be designated for compact cars and shall measure eight feet wide by 16 feet long. Such spaces must be signed and/or the space painted with “Compact Car Only”;
5.
Parking areas shall conform to Americans with Disabilities Act (ADA) standards for parking spaces (dimensions, van-accessible parking spaces, etc.). Parking structure vertical clearance and van-accessible parking spaces should refer to federal ADA guidelines; and
6.
Bicycle parking shall be on a two-foot by six-foot minimum concrete pad per bike, or within a garage or patio of residential use.
Figure 3.3.300.F(1) – Parking Area Layout  |
Figure 3.3.300.F(2) Disabled Person Parking Requirements  |
Table 3.3.300.F – Parking Area Layout | |||||||||
|---|---|---|---|---|---|---|---|---|---|
PARKING ANGLE < ° | CURB LENGTH | STALL DEPTH | AISLE WIDTH | BAY WIDTH | STRIPE LENGTH | ||||
SINGLE D1 | DOUBLE D2 | ONE WAY A1 | TWO WAY A2 | ONE WAY B1 | TWO WAY B2 | ||||
Standard Space (See Figure 3.3.300.F(2) for ADA space requirements) | 90° Compact | 9 ft. 8 ft. | 18 ft. 16 ft. | 36 ft. 32 ft. | 23 ft. 23 ft. | 23 ft. 23 ft. | 59 ft. 55 ft. | 59 ft. 55 ft. | 18 ft. 16 ft. |
60° | 10 ft. | 20 ft. | 40 ft. | 17 ft. | 18 ft. | 57 ft. | 58 ft. | 23 ft. | |
45° | 12 ft. | 18 ft. 6 in. | 37 ft. | 13 ft. | 18 ft. | 50 ft. | 55 ft. | 26 ft. 6 in. | |
30° | 17 ft. | 16 ft. 6 in. | 33 ft. | 12 ft. | 18 ft. | 45 ft. | 51 ft. | 32 ft. 8 in. | |
0° | 22 ft. | 8 ft. | 16 ft. | 12 ft. | 18 ft. | 28 ft. | 34 ft. | 8 ft. | |
Important cross-references: See also Article 2, Land Use (Zoning) Districts, for parking location requirements for some multifamily and commercial land uses; Chapter 3.1 SDC, Access and Circulation, for driveway standards; and Chapter 3.2 SDC, Landscaping, Street Trees, Fences and Walls. | |||||||||
(Ord. 08-06 § 3, 2008; Ord. 10-02 Exh. A § B, 2010; Ord. 20-09 § 3 (Exh. B), 2020; Ord. 21-04 §§ 19, 20, 2021)
§ 3.3.400 Bicycle parking requirements.
Except for single-family dwellings and duplex dwellings, all uses that are subject to land use review or site design review, as applicable, shall provide bicycle parking, in conformance with the standards in Table 3.3.400, and subsections (A) through (I) of this section.
A.
Minimum Required Bicycle Parking Spaces. Uses must provide bicycle parking spaces, as designated in Table 3.3.400. Where two options are provided (e.g., two spaces, or one per eight bedrooms), the option resulting in more bicycle parking is used.
Table 3.3.400 | ||
|---|---|---|
Use Categories | Specific Uses | Number of Spaces (near building entry) |
Residential Categories | ||
Multifamily dwellings (3 or more units) | Multifamily | 2 or 1 space per unit |
Group living | Group living | 2 or 1 space per every 2 bedrooms |
Dormitory | 1 per 2 bedrooms | |
Commercial Categories | ||
Retail sales and service | Retail sales and service | 2 or 1 space per every 10 automobile spaces required |
Lodging | 2 or 1 per every 10 automobile spaces required | |
Office | 2 or 1 space per every 10 automobile spaces required | |
Commercial outdoor recreation | 8 or 1 per 10 automobile spaces | |
Major event entertainment | 8 or 1 per 20 seats or per CU review | |
Industrial Categories | ||
Manufacturing and production | 2 or 1 per every 10 automobile spaces required | |
Warehouse and freight movement | 2 or 1 per floor area | |
Institutional Categories | ||
Basic utilities | Bus transit center | 8 |
Community service | Community service | 2 or 1 per every 10 required automobile spaces |
Park and ride | 8 | |
Parks (active recreation areas only) | 8 or per CU review | |
Schools | Grades 2 – 5 | 1 per classroom, or per CU review |
Grades 6 – 12 | 4 per classroom, or per CU review | |
Colleges | Excluding dormitories (see group living, above) | 2 or 4 per classroom, or per CU review |
Medical centers | 2 or 1 per 10 required automobile spaces, or per CU review | |
Religious institutions and places of worship | 2 or 1 per 10 required automobile spaces | |
Daycare | 2 or 1 per 2,000 sq. ft. of net building area | |
Other Categories | ||
Other categories | Determined through land use review, site design review or CU review, as applicable | |
B.
Exemptions. This section does not apply to single-family and duplex dwellings, home occupations, agriculture and livestock uses.
C.
Long-Term Bicycle Parking. Long-term bicycle parking (covered or enclosed) may be used to fulfill bicycle parking requirements.
D.
Location. Bicycle parking when located out-side the building it is intended to serve must be no farther from the main building entrance than the distance to the closest motor vehicle space, or 50 feet, whichever is less.
E.
Visibility and Security. Bicycle parking for customers and visitors of a use must be visible from street sidewalks or building entrances, so that it provides sufficient security from theft and damage.
F.
Design Options. Bicycle parking requirements for multiple-family uses and employee parking can be met by providing a bicycle storage room, bicycle lockers, racks, or other secure storage space inside or outside of the building. For example, covered bicycle parking may be under a stairway, projecting walls, or roof overhangs. Bicycle parking, when allowed within a public right-of-way, must conform to the city of Silverton’s public works design standards.
1.
Bike racks must be securely anchored to the ground, wall or other structure.
2.
Racks for required bicycle parking spaces shall ensure that bicycles may be locked to them without undue inconvenience. Provision of bicycle lockers for long-term (employee) parking is encouraged but not required.
3.
Bicycle parking spaces shall be at least two feet wide by six feet long and, when covered, have a vertical clearance of seven feet. An access aisle of at least five feet in width shall be provided and maintained beside or between each row of bicycle parking.
4.
Each bicycle parking space must be accessible without moving another bicycle.
G.
Lighting. For security, outdoor bicycle parking shall be at least as well lit as primary building entrances and vehicle parking areas.
H.
Reserved Areas. Areas designated for bicycle parking shall be clearly marked and reserved for bicycle parking only; for example, with appropriate signage or pavement stenciling.
I.
Hazards. Bicycle parking shall not impede or create a hazard to pedestrians. Parking areas shall be located so as to not conflict with vision clearance standards (Chapter 3.1 SDC).
(Ord. 08-06 § 3, 2008)
§ 3.3.500 Loading areas.
A.
Purpose. The purpose of this section is to provide standards for a minimum number of off-street loading spaces that will ensure adequate loading areas for large uses and developments, and to ensure that the appearance of loading areas is consistent with that of parking areas.
B.
Applicability. This section applies to residential multifamily projects with 50 or more dwelling units, and nonresidential and mixed-use buildings with 20,000 square feet or more total floor area.
C.
Number of Loading Spaces.
1.
Multifamily Residential Buildings. Buildings where all of the floor area is in residential use shall meet the following standards:
a.
Fewer than 50 dwelling units on a site that abuts a local street: No loading spaces are required.
b.
All other buildings: One space per 50 units.
2.
Nonresidential and Mixed-Use Buildings. Buildings where any floor area is in nonresidential uses shall meet the following standards:
a.
Less than 20,000 square feet total floor area: no loading spaces required.
b.
Twenty thousand to 50,000 square feet of total floor area: one loading space.
c.
More than 50,000 square feet of total floor area: two loading spaces.
D.
Size of Spaces. Required loading spaces shall be at least 35 feet long and 10 feet wide, and shall have a height clearance of at least 13 feet.
E.
Placement, Setbacks, and Landscaping. Loading areas shall conform to the setback and perimeter landscaping standards in Articles 2 and 3. Where parking areas are prohibited between a building and the street, loading areas are also prohibited. In the downtown commercial (DC) and downtown commercial fringe (DCF) districts, the reviewing body may approve a loading area adjacent to or within the street right-of-way through design review or conditional use review, as applicable, where it finds that loading and unloading operations are short in duration (i.e., less than one hour), do not obstruct traffic during peak traffic hours, and do not interfere with emergency response services.
(Ord. 08-06 § 3, 2008)
§ 3.4.010 Purpose and applicability.
A.
Purpose. This chapter provides general development standards and approval criteria for public improvements. The code incorporates by reference the city’s public facility master plans, including plans for domestic water (specifically Chapter 2 – Design Criteria), sanitary sewer (specifically Chapter 5 – Water Quality and Regulatory Issues and Chapter 10 – Recommended Plan), storm drainage (specifically Chapter 3 – Storm Water System Design Criteria and Chapter 7 – Water Quality), parks (specifically the Goals and Policies and Strategies and Actions), and transportation (specifically all TSP Standards in Chapter 5 for Street Functional Classification, Roadway Cross Section Standards, Mobility Standards, Access Management, Traffic Signal Spacing, and Local Street Connectivity). The code also incorporates by reference Silverton’s public works design standards (specifically Chapters 1 through 5 and Appendices A through H). This chapter is intended to provide minimum requirements for public facilities. It is not intended to duplicate or replace the design standards contained in the above documents.
B.
When Standards Apply. Development may occur only upon the city of Silverton reviewing and approving all proposed public facilities, finding them in conformance with requirements established in this chapter.
C.
Engineering Design Criteria, Standard Specifications and Details. Unless otherwise provided herein, construction, reconstruction, and repair of public facilities in the city of Silverton, including but not limited to transportation facilities, water, sanitary sewer, storm drainage, parks, and other facilities, shall occur only in accordance with the city of Silverton public works design standards. The design standards’ specifications, standards, and details are hereby incorporated into this code by reference.
D.
Conditions of Development Approval. Development shall not occur until all required public facilities are in place or guaranteed, in conformance with the provisions of this code and the city’s design standards. Improvements required as a condition of development approval, when not voluntarily accepted by the applicant, must be roughly proportional to the impact of the development on public facilities. Findings in the development approval must indicate how the required improvements are directly related and roughly proportional to the impact of development.
(Ord. 08-06 § 3, 2008; Ord. 19-09 § 1, 2019; Ord. 20-09 § 3 (Exh. B), 2020)
§ 3.4.100 Transportation standards.
A.
Development Standards. The following standards shall be met for all new uses and developments:
1.
All new lots created, consolidated, or modified through a land division, partition, lot line adjustment, lot consolidation, or street vacation must have frontage or approved access to a public street, except as specifically allowed through a planned development approval under Chapter 4.5 SDC or as provided for flag lots under Chapter 4.3 SDC, Land Divisions and Property Line Adjustments.
2.
Streets within or abutting a development shall be fully improved in accordance with the transportation system plan and the design standards. Three-quarter-street improvements may be accepted only when requiring a full-width street improvement cannot be justified based on the proportionate impact of the development on the transportation system, as approved by the public works director. Where a less than full street is allowed, the minimum total paved width shall not be less than 28 feet to provide for two travel lanes and bicycle lanes, unless otherwise approved by the public works director.
3.
Development of new streets, and additional street width or improvements planned as a portion of an existing street, shall be improved in accordance with this section, and public streets shall be dedicated to the applicable road authority.
4.
When development occurs with frontage on a substandard right-of-way and right-of-way dedication is not required as part of the development, the setback for the new development shall be calculated based on the anticipated future right-of-way.
5.
All new streets and drives shall be paved in accordance with design standards.
B.
Guarantee. The city may accept a future improvement guarantee in lieu of street improvements if the following conditions exist:
1.
Due to the developed condition of adjacent properties it is unlikely that street improvements would be extended in the near future, and deferring the improvement associated with the project under review does not, by itself, reduce street safety or capacity; and
2.
Deferral of the improvement, or a part of the improvement, does not create a potential safety hazard to motorists, bicyclists, or pedestrians; and
3.
Deferral of the improvement does not preclude future improvements in conformance with city plans; or
4.
The improvement is not roughly proportional to the proposed development; and
5.
The applicant has not voluntarily agreed to complete the street improvements with proposed development.
C.
Creation of Rights-of-Way for Streets and Related Purposes. Streets shall be created through the approval and recording of a final subdivision or partition plat; except the city may approve the creation of a street by acceptance of a deed; provided, that the street is deemed in the public interest by the city council for the purpose of implementing the transportation system plan, and the deeded right-of-way conforms to the standards of this code.
D.
Creation of Access Easements. The city may approve an access easement when the easement is necessary to provide for access and circulation in conformance with Chapter 3.1 SDC, Access and Circulation. Access easements shall be created and maintained in accordance with applicable provisions of the Uniform Fire Code.
E.
Street Location, Width, and Grade. The location, width and grade of all streets shall conform to the transportation system plan and approved street plans or subdivision plats. Street location and design shall be determined in relation to existing and planned streets, topographic conditions, public convenience and safety, and in appropriate relation to the proposed use of the land to be served by such streets as follows:
1.
Street grades shall be approved by the public works director in accordance with the design standards; and
2.
Where the location of a street is not shown in an existing street plan, the location of streets in a development shall either:
a.
Provide for the continuation and connection of existing streets in the surrounding areas, conforming to the street standards of this section; or
b.
Conform to a street plan adopted by the city if it is impractical to connect with existing street patterns because of particular topographical or other existing conditions of the land. Such a plan shall be based on the type of land use to be served, the volume of traffic, the capacity of adjoining streets, and the need for public convenience and safety.
F.
Minimum Rights-of-Way and Street Sections. Street rights-of-way and improvements must conform to the standards and specifications of the transportation system plan and design standards. Where a range of right-of-way or roadway width is indicated, the width shall be the narrower in the range unless unique and specific conditions exist as determined by the reviewing body based upon the following factors:
1.
Street classification in the transportation system plan;
2.
Anticipated traffic generation;
3.
On-street parking needs;
4.
Sidewalk and bikeway requirements based on anticipated level of use;
5.
Requirements for placement of utilities;
6.
Street lighting;
7.
Minimize drainage, slope, and sensitive lands impacts;
8.
Street tree location, as provided for in Chapter 3.2 SDC;
9.
Protection of significant vegetation, as provided for in Chapter 3.2 SDC;
10.
Safety and comfort for motorists, bicyclists, and pedestrians;
11.
Street furnishings (e.g., benches, lighting, bus shelters, etc.), when provided;
12.
Access needs for emergency vehicles; and
13.
Transition between different street widths (i.e., existing streets and new streets).
G.
Subdivision Street Connectivity. All subdivisions shall conform to all the following access and circulation design standards, as applicable:
1.
Connectivity to Abutting Lands. The street system of proposed subdivisions shall be designed to connect with existing, proposed, and planned streets outside of the subdivision as provided in this section. Wherever a proposed development abuts unplatted land or a future development phase of the same development, street stubs shall be provided to allow access to future abutting subdivisions and to logically extend the street system into the surrounding area. All street stubs shall be provided with a temporary turnaround unless specifically exempted by the fire marshal, and the restoration and extension of the street shall be the responsibility of any future developer of the abutting land.
2.
When Abutting an Arterial Street. Property access to abutting arterials shall be minimized.
Where such access is necessary, shared driveways may be required in conformance with SDC § 3.1.200. If vehicle access off a secondary street is possible, then the road authority may prohibit access to the arterial.
3.
Continuation of Streets. Planned streets shall connect with surrounding streets to permit the convenient movement of traffic between residential neighborhoods and to facilitate emergency access and evacuation. Connections shall be designed to meet or exceed the standards in subsection (G)(4) of this section and to avoid or minimize through traffic on local streets. Appropriate design and traffic control and traffic calming measures, as provided in subsection (H) of this section, are the preferred means of discouraging through traffic.
4.
Street Connectivity and Formation of Blocks. In order to promote efficient vehicular and pedestrian circulation throughout the city, subdivisions and site developments of more than two acres shall be served by a connecting network of public streets and/or pedestrian access ways, in accordance with the following standards (minimum and maximum distances between two streets or a street and its nearest access way):
a.
Residential districts: minimum of 100-foot block length and maximum 600-foot length with a desired block length of 500 feet;
b.
Downtown commercial and downtown commercial fringe districts: block lengths shall be consistent with the existing town plat, as of November 5, 2008;
c.
General commercial district: minimum of 100-foot block length and maximum 600-foot length;
d.
Not applicable to the industrial districts.
Figure 3.4.100.G – Street Connectivity and Formation of Blocks  |
5.
Pedestrian Access Way Standards. Where it is impractical to make a street connection in conformance with the standards in subsection (G)(4) of this section, a pedestrian access way must be provided at or near the middle of a block in lieu of the street connection, as generally shown in Figure 3.4.100.G. The city may also require developers to provide an access way where a cul-de-sac or other street is planned and the access way would connect the streets or provide a connection to other developments. Such accessories shall conform to all of the following standards:
a.
Access ways shall be no less than 20 feet wide with a minimum eight-foot-wide paved surface, or wider if utilities are provided, and located within a right-of-way or easement allowing public access and, as applicable, emergency vehicle access;
b.
If the streets within the subdivision or neighborhood are lighted, access ways in the subdivision must also be lighted. Access way lighting must provide at least two footcandles of illumination. Light standards shall be directed downward only and shielded to prevent lighting spillover and to prevent light pollution in the night sky;
c.
A right-of-way or public access easement provided in accordance with subsection (G)(5)(a) of this section that is less than 20 feet wide may be allowed on steep slopes where the decision body finds that stairs, ramps, or switch-back paths are necessary;
d.
Access ways must be wheelchair accessible except where existing topography precludes access; and
e.
The city may require landscaping and fences as part of the required access way improvement to buffer pedestrians from adjacent vehicles, or to screen access ways from the view of adjacent residences.
6.
Pedestrian Access Way Exceptions. Access ways need not be required where one or more of the following conditions exist:
a.
Physical or topographic conditions make a street or access way connection impracticable. Such conditions include but are not limited to freeways, railroads, steep slopes, wetlands, or other bodies of water where a connection could not reasonably be provided;
b.
Buildings or other existing development on adjacent lands physically preclude a connection now or in the future considering the potential for redevelopment; or
c.
Where access ways would violate provisions of leases, easements, covenants, restrictions or other existing agreements, which preclude a required street or access way connection.
H.
Traffic Signals and Traffic Calming Features.
1.
Traffic signals shall be required with development when traffic signal warrants are met, in conformance with the Highway Capacity Manual and Manual of Uniform Traffic Control Devices. Where a proposed development results in an immediate need for a traffic signal, a signal meeting approved specifications shall be installed in conformance with the roadway authority’s requirements prior to occupancy of the development. The developer’s cost and the timing of improvements may be partially reimbursable through system development charge credits or other reimbursement approved by the public works director.
2.
When an intersection meets or is projected to meet traffic signal warrants, the city may accept alternative mitigation, such as a roundabout, in lieu of a traffic signal, if approved by the public works director and the applicable road authority if different than the city.
3.
The city may require the installation of traffic calming features such as curb extensions, reduced street width (parking on one side), medians with pedestrian crossing refuges, traffic tables or other features to reduce vehicle speeds in neighborhoods and other areas with high pedestrian use.
I.
Future Street Plan and Extension of Streets.
1.
A future street plan shall be filed by the applicant in conjunction with an application for a subdivision in order to facilitate orderly development. The plan must show the pattern of existing and proposed future streets from the boundaries of the proposed land division and include other divisible parcels within 600 feet surrounding and adjacent to the subject site. The street plan is not binding; rather, it is intended to show potential future street extensions with future development.
2.
Streets shall be extended to the boundary lines of the parcel or tract to be developed when the city determines that the extension is necessary to give street access to, or permit a satisfactory future division of, adjoining land. The point where the streets temporarily end shall conform to subsections (I)(2)(a) through (d) of this section:
a.
These extended streets or street stubs to adjoining properties are not considered to be cul-de-sacs since they are intended to continue as through streets when the adjoining property is developed.
b.
A temporary barricade approved by the public works director shall be constructed at the end of the street by the subdivider and shall not be removed until authorized by the city or other applicable agency with jurisdiction over the street. The cost of the barricade shall be included in the street construction cost.
c.
Temporary street ends must provide turnarounds constructed to Uniform Fire Code standards for streets over 150 feet in length. See also SDC § 3.1.200.
d.
A one-foot-wide reserve strip shall be required to be dedicated to the city at the terminus of the stub street.
J.
Street Alignment and Design. The alignment, design and construction of all streets, including vehicle and bicycling travel lanes, bus pullouts and waiting areas, sidewalks, planter strips, tree wells, street furnishings, driveway approaches (dimensions, spacing, access limitations), intersections, grades, horizontal and vertical curves, cul-de-sacs, and other improvements, shall conform to the city of Silverton design standards.
K.
Streets Adjacent to Railroad Right-of-Way. When a transportation improvement is proposed within 300 feet of a public railroad crossing, or a modification is proposed to an existing public crossing, the Oregon Department of Transportation and the rail service provider shall be notified and given an opportunity to comment. Private crossing improvements are subject to review and licensing by the rail service provider.
L.
Development Adjoining Arterial Streets. Where a development adjoins or is crossed by an existing or proposed arterial street, residential access shall be separated from through traffic and designed to minimize traffic conflicts. (See also the access requirements under SDC § 3.1.200.) The reviewing body may require one or more of the following improvements to ensure the continued operational safety of the transportation system and land use compatibility:
1.
A parallel access street (frontage road) along the arterial street with a landscape median separating the two streets.
2.
Deep lots (120 feet or greater) abutting the arterial street to provide at least 10 feet of landscape buffering along the arterial, provided vehicle access is from a secondary street. Where a secondary street is not available and direct access to the arterial is necessary, such lots shall combine and share driveways.
3.
Screen planting within a nonaccess reservation (e.g., public easement or tract) of not less than 10 feet in width at the rear or side property line along the arterial.
4.
Other treatment approved by the city that is consistent with the intent of this section.
M.
Private Streets. Private streets are permitted solely within manufactured home parks when the review body determines that public streets are not needed to provide for circulation and/or access to neighboring properties.
N.
Street Names. The developer shall submit proposed street names to the city of Silverton community development department for review and submittal to the Marion County road naming committee for approval prior to recording the final plat. No new street name shall be used that duplicates or could be confused with the name of an existing street in the vicinity. Street names, signs, and numbers shall conform to the established pattern in the surrounding area, except as requested by emergency service providers.
O.
Survey Monuments. Upon completion of public improvements and prior to acceptance by the city, it shall be the responsibility of the developer’s registered professional land surveyor to establish survey monuments in accordance with city and Marion County standards and provide certification to the public works director of all public improvements and as-builts.
P.
Street Signs. All street signs must be reviewed and approved by the public works department or other roadway authority, as applicable, before they are installed. The developer is responsible for the cost of all signs required in the development. Street name signs shall be installed at all street intersections. Stop signs and other signs may also be required.
Q.
Mailboxes. Plans for mailboxes must be approved by the United States Postal Service and the public works department prior to installation.
R.
Street Light Standards. Street lights must be reviewed and approved by the public works department prior to installation.
S.
Street Cross-Sections. Cross-sections shall conform to the city of Silverton public works design standards. The final lift of asphalt or concrete pavement shall be placed on all new constructed public roadways prior to final city acceptance of the roadway unless otherwise approved by the public works director.
T.
Alley Standards. Use of alleys may be considered as part of residential neighborhood design. A narrower minor local street (28-foot paved surface) will be allowed with alley access because the alley will reduce some of the parking and access functions usually found on the frontage street. To the maximum extent possible, all private utilities must be located in the alley and curb cuts will not be permitted along the frontage street. The standard six-foot planter strip and five-foot setback sidewalks are required along the frontage street. Alleys shall be consistent with the city’s public works design standards, paved with a dustless surface (i.e., concrete or asphaltic concrete), and shall follow the general development standards governing streets. As an incentive, lots with alley access may be up to 1,000 square feet smaller than the standard minimum lot size of the zone.
U.
Level of Service Standard.
1.
City performance standards shall be used to evaluate developments impacting city or county facilities. The level of service standard shall be LOS D based on the Highway Capacity Manual methodology and a v/c ratio of 0.85 for signalized and all-way stop controlled intersections. For unsignalized intersection, the level of service standard shall be LOS D based on the Highway Capacity Manual and a v/c ratio of 0.90. ODOT v/c ratio standards shall apply to ODOT facilities.
2.
For signalized intersections, adequate level of service is LOS D, based on a weighted average of vehicle delay for the intersection.
3.
For stop-controlled intersections, adequate level of service is LOS D. Level of service for two-way stop-controlled intersections is based on individual vehicle movement, and all-way stop controlled intersections is based on a weighted average of vehicle delay for the intersection.
4.
An amendment or other land use application that requires analysis of traffic capacity and allows development that either (a) may cause a transportation facility to perform below the standards established in subsections (U)(1) and (U)(2) of this section, or (b) adds vehicle trips to a facility that is already performing below the standards established in subsections (U)(1) and (U)(2) of this section may be approved if:
a.
Development resulting from the amendment or other land use application will mitigate the impacts of the amendment or other land use application in a manner that avoids further degradation to the performance of the facility by the time of development through one or more of the following:
i.
One or more combination of transportation improvements or measures are imposed to mitigate the transportation impacts of the amendment or other land use application in a manner that avoids further degradation to the performance of the facility by the time of any development.
ii.
On-site and off-site improvements beyond required frontage improvements.
iii.
Payment of a fee in lieu of construction.
iv.
Correction of off-site transportation deficiencies within the study area that are not substantially related to development impacts.
v.
Construction of on-site facilities or facilities located within the right-of-way adjoining the development site that exceed minimum required standards and that have a transportation benefit to the public.
V.
Transit Access and Supportive Improvements. Development that is proposed adjacent to an existing or planned transit stop, as designated in an adopted transportation or transit plan, shall provide the following transit access and supportive improvements in coordination with the transit service provider:
1.
Reasonably direct pedestrian connections between the transit stop and primary entrances of the buildings on site. For the purpose of this section, “reasonably direct” means a route that does not deviate unnecessarily from a straight line or a route that does not involve a significant amount of out-of-direction travel for users.
2.
The primary entrance of the building closest to the street where the transit stop is located is oriented to that street.
3.
A transit passenger landing pad that is ADA accessible.
4.
An easement or dedication for a passenger shelter or bench if such an improvement is identified in an adopted plan.
5.
Lighting at the transit stop.
6.
Other improvements identified in an adopted transportation or transit plan.
(Ord. 08-06 § 3, 2008; Ord. 10-02 Exh. A § B, 2010; Ord. 19-09 § 2, 2019; Ord. 20-09 § 3 (Exh. B), 2020)
§ 3.4.200 Public use (park) areas.
A.
Dedication of Public Use (Park) Areas.
1.
The availability of parkland and open space is a critical element in maintaining and improving the quality of life in Silverton. All new development that results in the creation of new residential dwelling units (subdivisions, partitions, planned unit developments, multifamily developments, manufactured home parks, etc.) is required to provide through payment and/or dedication public use areas (such as parks, playgrounds, community centers, trails, etc.) based on the city’s most current parks and recreation master plan.
2.
Where a proposed park, playground, or other public use area shown in a plan adopted by the city is located in whole or in part in a subdivision, planned unit development and/or other development proposal, the city may require the dedication and/or reservation and/or improvement thereof for public use (parks, playgrounds, trails, etc.) purposes; provided, that the impact of the development on the city park system is roughly proportionate to the dedication/reservation/improvement being required. However, the city is under no obligation to accept such areas or improvements offered for dedication or sale.
3.
The amount of land and park improvements, when required, shall be proportionate to the impact the development will have in generating park need based on the number of proposed dwelling units. All required improvements shall conform to the level of service standards identified in the city of Silverton’s most current parks master plan and as refined and adopted by the parks and recreation system development charges (SDC) methodology. The 2008 park and recreation master plan estimated a 2030 population of 14,400 and need for 115.25 acres of new parklands (based on eight acres of neighborhood park and community parkland per 1,000 population), 20 acres of new natural areas, 13,467 lineal feet of trails, and other improvements (community center, swimming pool, etc.), to serve the new need. (Note: This amount of needed land does not address the existing deficiencies since improvement fee SDCs may only be used for growth needs.) The required parkland dedication is in addition to any street tree planter strips, stormwater facilities, or other open space improvements that may be donated or otherwise required.
4.
Any required parkland dedication and/or improvements in excess of the proportionate share impact of the development shall be eligible for reimbursement. The city may accept a cash payment (also known as a system development charge) in lieu of parkland dedication and/or improvement where it finds that due to location, size, or other considerations the proposed land and/or improvements would not provide suitable park facilities.
5.
The Silverton city council may permit a noncity (public or private) entity to own and manage the park area required in subsection (A)(3) of this section; provided, that the city and park provider shall first enter into a legal agreement assuring that city residents will have public access to the park. The agreement, at a minimum, shall also describe the types of park uses and facilities that are to be provided, park operating hours, and ongoing maintenance responsibilities. All property taxes are the responsibility of the property owner.
6.
Land that has been required to meet park needs shall be dedicated to the city or if it is to be owned by a public or private entity then the city council shall approve of the alternative ownership and legal documents acceptable to the city attorney shall be provided that assure public access, park operating hours, and ongoing maintenance responsibilities.
7.
Dedication Procedures. Prior to approval of the final plat, the developer shall dedicate land as previously determined by the city in conjunction with approval of the tentative plan. Dedication of land in conjunction with multifamily development (when there is no final plat) shall be required prior to the issuance of permits and commencement of construction.
a.
Prior to acceptance of required parkland dedications, the applicant/developer shall complete the following items for all proposed dedication areas:
i.
The developer shall clear, fill and/or grade all land to the satisfaction of the city, install sidewalks on the parkland adjacent to any street and seed the parkland; and
ii.
The developer shall submit a Phase 1 Environmental Site Assessment completed by a qualified professional according to the American Society of Testing and Materials Standards (ASTM 1527). The results of this study shall reflect a clean environmental record.
b.
Additional Requirements.
i.
In addition to a formal dedication on the plat to be recorded, the subdivider shall convey the required lands to the city by general warranty deed. The developer of a multifamily development or manufactured home park shall deed the lands required to be dedicated by a general warranty deed. In any of the above situations, the land so dedicated and deeded shall not be subject to any reservations of record, encumbrances of any kind or easements which, in the opinion of the director, will interfere with the use of the land for park, open space, or recreational purposes.
ii.
Where any reservations, encumbrances, or easements exist, the city may require payment in lieu of dedication of land unless it chooses to accept the land subject to the encumbrances.
c.
Phased Development. In a phased development, the required parkland shall be dedicated prior to approval of the final plat for the first phase. Improvements to the land as required by subsection (A)(7)(a)(i) of this section shall be made prior to approval of the final plat for the phase that includes the parkland.
8.
Cash in Lieu of Dedication. At the city’s discretion, the city may accept cash payment in lieu of land dedication. The amount of the cash payment shall be set by the city council by resolution and shall be based on the parks and recreation system development charges (SDC) methodology update report. The fee shall be paid prior to the signing of the final plat, or with multifamily development (when there is no final plat) payment shall be required prior to the issuance of permits and prior to the commencement of construction.
B.
System Development Charge Credit. Dedication of land or facilities to the city for parks, voluntary or otherwise, may be eligible for credit toward any required system development charge for parks.
(Ord. 08-06 § 3, 2008)
§ 3.4.300 Sanitary sewers, water, street lights and fire protection.
A.
Sanitary Sewer, Storm Drainage and Water System Improvements. Sanitary sewer system and water system improvements shall be installed with new development in accordance with the city’s sanitary sewer master plan, water system master plan, and public works design standards. When streets are required to be stubbed to the edge of the subdivision, sewer and water system improvements shall also be stubbed with the streets, except where the public works director finds that future extension is not practical due to topography or other constraints. Where public sanitary sewer or water service is not available within 300 feet of a property, private wells and septic systems may provide service for the development of a single-family dwelling, duplex dwelling, or use serving the public on parcels containing at least two acres; provided, that a petition for improvement/waiver of remonstrance is signed for their share of the costs for and future connection to public water and sewer services. These provisions are supplementary to the provisions in Chapters 13.12 and 13.16 SMC. Any private well or septic system allowed by this section must be approved by Marion County and the State Water Resources Department.
B.
Plan Approval. Development permits for sewer and water system improvements shall not be issued until the public works director has approved all sanitary sewer and water plans in conformance with city standards.
C.
Over-Sizing Facilities. The city may require as a condition of development approval that sewer and water systems serving new development be sized to accommodate future development within the area as projected by the applicable water and sewer master plans and public works design standards. Oversizing of facilities may be eligible for credit toward system development charges.
D.
Street Lights. Street lights shall be provided in all developments within the city and shall be provided in accordance with the city’s design standards. The reviewing body may add street lights at other locations and authorize specific exceptions to the above priorities when necessary in order to enhance the public safety and welfare.
E.
Fire Protection. Developers shall provide third party verification of existing and proposed water service mains and hydrant flow supporting the development site. Hydrant flow analyses and plans for hydrants and water service mains shall be subject to review and approval by the fire marshal as part of the development review process.
F.
Inadequate Facilities. Development may only occur where existing or proposed public facilities are adequate to serve the site as required per subsection (A) of this section. If services do not meet these standards, service upgrades may be required or the development permits may be restricted by the city. Deficiencies in the existing water or sewer system that cannot be rectified by the development and that if not rectified will result in a threat to public health or safety, surcharging of existing mains, or violations of state or federal standards pertaining to operation of domestic water or sewerage treatment systems will not be approved.
(Ord. 08-06 § 3, 2008; Ord. 10-02 Exh. A § B, 2010; Ord. 21-04 § 21, 2021)
§ 3.4.400 Storm drainage and erosion control.
A.
General Provisions. The city shall issue a development permit only where adequate provisions for stormwater runoff and erosion control have been made in conformance with the city of Silverton storm drainage master plan and public works design standards.
B.
Accommodation of Upstream Drainage. Culverts and other drainage facilities shall be large enough to accommodate existing stormwater. Such facilities shall be subject to review and approval by the public works director.
C.
Effect on Downstream Drainage. Where it is anticipated by the public works director that the additional runoff resulting from the development will overload an existing drainage facility, the city shall withhold approval of the development until provisions have been made for improvement of the potential condition or until provisions have been made for storage of additional runoff caused by the development. Stormwater detention and/or retention facilities, including water quality treatment, may be required in conformance with city standards.
D.
Over-Sizing. The city may require as a condition of development approval that storm drainage systems serving new development be sized to accommodate future development within the area as projected by the applicable storm drainage master plan. Over-sizing of facilities may be eligible for credit towards SDCs.
E.
Existing Watercourse. Where a proposed development is traversed by a watercourse, drainage way, channel, or stream, there shall be provided a stormwater easement or drainage right-of-way conforming substantially to the lines of such watercourse and such further width as will be adequate for conveyance and maintenance to protect the public health and safety.
F.
Erosion Control. Specific erosion control measures shall be designed, installed and monitored in conformance with the city’s design standards. City-approved erosion control measures must be in place prior to, during and after construction activities for projects that disturb one or more acres of land over a period of time. A National Pollution Discharge Elimination System (NPDES) permit must be obtained from the Department of Environmental Quality prior to the issuance of a development permit or land use permit.
G.
Detention. All required stormwater detention must provide for the 25-year storm event. Detention shall be located in underground facilities, or, if aboveground detention is utilized, it shall be with the review and approval of the public works director.
(Ord. 08-06 § 3, 2008)
§ 3.4.500 Sidewalks.
A.
Requirement. Sidewalks shall be constructed on all public streets in the city by the owners of property next adjacent thereto. As such, sidewalks shall be constructed in accordance with the specifications hereinafter provided. All development for which land use applications are required must include sidewalks adjacent to public streets. This requirement also applies to new single-family houses and duplexes if they are located on arterial or collector streets or on curbed local streets if there is an existing sidewalk within 500 feet on the same side of the street.
In the case of arterial or collector streets, sidewalks shall be built during their construction and considered during their reconstruction. This provision shall also apply to local streets that serve commercial and multifamily development. Sidewalks are required on both sides of all streets except in hillside developments and mini-subdivisions. If an interim street standard is being constructed which does not include bike lanes or sidewalks, interim bikeways or walkways for pedestrians shall be provided through construction of paved roadway shoulders at least eight feet in width on arterials and six feet on other streets.
B.
Specifications for Construction. Specifications for the construction of the various kinds of walks provided for have been made by the city engineer and filed in the office of the city recorder, which specifications are hereby especially referred to and by reference are made a part hereof; provided, however, that changes may be made in such specifications by the city council at any time, and when so made and approved and filed in the office of the city recorder, such changed or amended specifications shall become a part hereof the same as though such specifications were now on file in the office of the city recorder.
C.
Mid-Block Requirements. In the case of blocks greater than 500 feet in length, the review body shall require mid-block pedestrian walks and/or bikeways on a right-of-way at least 20 feet in width with a minimum eight-foot-wide paved surface. All walkways or bikeways between streets shall be subject to the requirements of the public works director.
D.
Design, Width, and Location. All sidewalks must be constructed, replaced or repaired in accordance with the Silverton transportation system plan and the Standard Construction Specifications. The required width and location of sidewalks is as follows:
1.
The required width for a sidewalk on an arterial or collector street is six feet. This width may be reduced to five feet if the sidewalk is separated from the curb by a landscaped planter strip at least five feet wide. In those instances where there is inadequate right-of-way for additional width and no additional right-of-way can be obtained as a condition of development approval, the sidewalk width may be reduced to five feet. In all cases, any right-of-way remaining outside the sidewalk is to be landscaped and maintained by the adjoining property owner.
2.
Sidewalks along residential and other local streets must be a minimum of five feet in width. Street trees shall be selected from the list of approved street trees established by the city. Other tree species may be approved if they have similar qualities as those on the list. The planter strip shall be of permeable materials.
3.
In the downtown area sidewalks shall be provided consistent with the Silverton downtown master plan.
4.
Regardless of other provisions contained in this section, any sidewalk project that is less than 200 feet in length and connects on either end to an existing sidewalk may be designed to match the existing pattern with the approval of the city public works director.
5.
Where obstructions exist or are proposed (including but not limited to mail boxes, utility poles, trees, planters, fire hydrants, signs, benches, bus stops, etc.), provisions must be made to maintain a minimum of four feet of unobstructed sidewalk width on local streets, five feet on collector and arterial streets, and five feet in the downtown commercial district.
6.
Maintenance of sidewalks and planter strips shall be the continuing obligation of the adjacent property owner. Planter strips shall be landscaped and maintained in like manner to the front yard setback requirements of Article 3, Community Design Standards.
7.
Sidewalks shall be designed to parallel streets in line and grade and shall avoid unnecessary meandering from the curb line and elevation changes except as necessary to avoid significant trees or traverse topographic barriers. All sidewalks shall be constructed to the official city specifications grade and at such lateral grade or slope as has been or may be specified in the general specification therefor by the city engineer. Grades shall be furnished without charge to property owners, when applied for, for the purpose of constructing sidewalks.
8.
Pedestrian/bike access ways not adjacent to a public street shall be a minimum of 20 feet wide and dedicated to the public. The access way improvement shall be a minimum eight-foot-wide paved surface and shall be provided with pedestrian-scaled lighting along the access way. Lighting shall not shine into adjacent residences. Trees shall be provided within the dedicated access way in accordance with the requirements of Chapter 3.2 SDC.
E.
Conformance to Street Grades. All sidewalks constructed adjacent to a street must be placed upon the street grade as established at the time of sidewalk construction. If a space is left between the property line and the sidewalk and/or between the sidewalk and the curb, the space shall be filled and surfaced with earth or other approved material level with the sidewalk. Grade shall be furnished without charge to property owners, when applied for, for the purpose of constructing sidewalks.
F.
Timing of Sidewalk Construction. Sidewalk construction may be deferred until the proposed improvement on the property is completed. No occupancy permit shall be issued by the building official for a development until the provisions of this title are satisfied. The public works director shall require a future improvement assurance (as described in SDC § 3.4.700) when, in his opinion, the construction of the sidewalk is impractical for one or more of the following reasons:
1.
In the case of all property other than industrial:
a.
The street is not improved with curbs.
b.
Forthcoming installation of public utilities or street paving would be likely to cause severe damage to the new sidewalk.
c.
Street right-of-way is insufficient to accommodate a sidewalk on one or both sides of the street.
d.
Topography or elevation of the sidewalk base area makes construction of a sidewalk impractical or economically infeasible.
e.
The location is not on a designated collector or arterial street.
f.
Less than 70 percent of the property frontage is developed with sidewalks along that side of the block, except in the case of a new or developing subdivision, in which case, sidewalks shall not be deferred.
2.
In the case of industrial property:
a.
The frontage considered for the deferral is not on a major pedestrian route to a school, shopping center, park, church, or other pedestrian traffic generator, as determined by the public works director.
3.
The deferral of the sidewalk construction does not pose a threat to the welfare and safety of the public based upon a review of the pedestrian/vehicular traffic, the width and condition of the street, and of the on-street parking.
4.
Whenever the construction of a sidewalk has been deferred, the property owner shall, unless otherwise allowed by the public works director or his/her designee:
a.
Grade and slope the area to the future sidewalk grade;
b.
Avoid planting trees in the sidewalk area, or building fences, retaining walls, steps, or other impediments to the future sidewalk; and
c.
Note on the plans for the development that a deferment has been granted but that sidewalk construction may be ordered by the city council at any time.
5.
Sidewalk construction which has been deferred pursuant to this section may be initiated by resolution of the city council.
(Ord. 08-06 § 3, 2008; Ord. 10-02 Exh. A § B, 2010)
§ 3.4.600 Utilities.
A.
Underground Utilities.
1.
Generally. All new utility lines including, but not limited to, those required for electric, communication, lighting, and cable television services and similar facilities shall be placed underground, except for surface-mounted transformers, surface-mounted connection boxes and meter cabinets which may be placed above ground, temporary utility service facilities during construction, and high-capacity electric lines operating at 50,000 volts or above, subject to review and approval by the public works director.
2.
New Development. The following additional standards apply to all new development, in order to facilitate underground placement of utilities:
a.
The developer shall make all necessary arrangements with the serving utility to provide the underground services. Care shall be taken to ensure that all aboveground equipment does not obstruct required vision clearance areas;
b.
The city reserves the right to approve the location of all surface-mounted facilities;
c.
All underground utilities, including sanitary sewers and storm drains installed in streets by the developer, shall be constructed prior to the surfacing of the streets; and
d.
Stubs for service connections shall be sufficient in length to avoid disturbing the street improvements when service connections are made.
3.
Exception to Undergrounding Requirement. Exceptions to the undergrounding requirement may be granted by the public works director due to physical constraints, such as steep topography, sensitive lands or existing development conditions that make undergrounding impractical.
(Ord. 08-06 § 3, 2008; Ord. 10-02 Exh. A § B, 2010)
§ 3.4.700 Construction plan approval and assurances.
A.
Plan Approval and Permit. No public improvements, including sanitary sewers, storm sewers, streets, sidewalks, curbs, lighting, parks, or other requirements, shall be undertaken except after the plans have been approved by the city, permit fee paid, and permit issued. The permit fee is required to defray the cost and expenses incurred by the city for construction and other services in connection with the improvement. The permit fee shall be set by the city council.
B.
Performance Guarantee. The city may require the developer or subdivider to provide assurance, bonding or other performance guarantees to ensure completion of required public improvements. See Chapter 4.2 SDC, Land Use Review and Design Review, and Chapter 4.3 SDC, Land Divisions and Property Line Adjustments.
1.
The assurance shall contain the time within which the obligation is to be met. It may take the form of a surety or performance bond, cash, a negotiable security deposit, a mutual improvement agreement, a monetary contribution to a fund for future improvements if established by a separate city ordinance or other guarantees approved by the city attorney sufficient to cover the cost of the work as estimated by the city. The bond shall be conditioned upon the developer’s carrying out the obligation and fulfilling the other requirements of this title that bear on the approval of the development. The deposit or bond shall be forfeited to the city if the developer does not fulfill the requirements. The bond or deposit shall remain in the custody of the city until the obligation is completed or the bond or deposit is forfeited, or shall be placed in an escrow account subject to city control.
2.
If the public works director finds that a developer is not fulfilling an obligation, the director shall, in written notice to the developer and the developer’s surety, specify the details of noncompliance. Unless the public works director allows more time for compliance because of circumstances beyond the developer’s control, within 30 days after receiving the notice, the developer or the developer’s surety shall commence the compliance and proceed diligently to complete fulfillment of the obligation.
a.
If the developer or the developer’s surety does not commence the compliance within the 30 days or the additional time allowed by the public works director, or has so commenced but fails diligently to complete the compliance, or the compliance is otherwise not completed within the time specified in granting the development approval, the city may take the following action:
i.
Enter upon the site of the development and carry out the obligation in accordance with the provisions agreed upon under the acknowledgement.
ii.
Notify the developer and the developer’s surety of the developer’s failure to perform as required by this code.
iii.
Demand payment from the developer for the unfulfilled obligation.
iv.
If the security for the obligation is a bond, notify the surety that has furnished the bond that reimbursement for the expense for fulfillment of the obligation is due and payable to the city or, if the security is a deposit of cash or other assets, appropriate as much of the deposit as is necessary to recoup the expense.
v.
Void all approvals granted in reliance on the improvement assurance.
b.
If a bond or other required security is not sufficient to compensate the city for expenses necessary to fulfill the obligation, the amount due to the city for the obligation is a lien in favor of the city and upon the entire contiguous real property of the owner of the land subject to the obligation.
c.
The lien attaches upon the filing with the city recorder of notice of the claim for the amount due for the fulfillment of the obligation. The notice shall demand the amount due, allege the insufficiency of the bond or other security to compensate the city fully for the expense of the fulfillment of the obligation, and allege the developer’s failure to do the required obligation.
d.
The lien may be foreclosed in the manner prescribed by law for foreclosing other liens on real property.
e.
The remedies set forth for noncompliance are cumulative. In addition to the remedies set forth above, noncompliance by the developer or his surety with any term of a performance guarantee shall entitle the city to pursue any civil remedy permitted by law.
C.
Petition for Improvement/Waiver of Remonstrance. Existing single-family or duplex residential lots of record and lots created by a land partition may be developed, provided the lots are subject to a petition for improvement/waiver of remonstrance for a future assessment district for the lacking public facilities as determined and approved by the public works director in consultation with the Silverton fire district.
(Ord. 08-06 § 3, 2008; Ord. 21-04 § 22, 2021)
§ 3.4.800 Installation.
A.
Conformance Required. Improvements installed by the developer, either as a requirement of these regulations or at his/her own option, shall conform to the requirements of this chapter, approved construction plans, and to improvement standards and specifications adopted by the city.
B.
Adopted Installation Standards. The Standard Specifications for Public Works Construction, Oregon Chapter A.P.W.A., are hereby incorporated by reference; other standards may also be required upon recommendation of the public works director.
C.
City Inspection. Improvements shall be constructed under the inspection and to the satisfaction of the city. The city may require minor changes in typical sections and details if unusual conditions arising during construction warrant such changes in the public interest. Modifications to the approved design requested by the developer may be subject to review under Chapter 4.6 SDC, Modifications to Approved Plans and Conditions of Approval. Any monuments that are disturbed before all improvements are completed by the subdivider shall be replaced prior to final acceptance of the improvements.
D.
Engineer’s Certification and As-Built Plans. A registered civil engineer shall provide written certification in a form required by the city that all improvements, workmanship, and materials are in accordance with current and standard engineering and construction practices, conform to approved plans and conditions of approval, and are of high grade, prior to city acceptance of the public improvements, or any portion thereof, for operation and maintenance. The developer’s engineer shall also provide one set of record drawings in photo Mylar (three-mil. minimum); and a CD containing the digital record drawings in both Auto-CAD (check with public works department to determine release format) and Portable Document Format (.pdf) format, in conformance with design standards specifications, for permanent filing with the city.
(Ord. 08-06 § 3, 2008; Ord. 14-01 § 1 (Exh. A), 2014)
§ 3.4.900 Easements.
A.
Provision. The developer is responsible for making arrangements with the city, the applicable district, and each utility franchise for the provision and dedication of utility easements necessary to provide full services to the development. Public main line utility easements shall conform to city specification. See the design standards.
B.
Recordation. As determined by the public works director, all easement facilities required under this chapter shall be recorded after final acceptance of public improvements. See also Chapter 4.3 SDC, Land Divisions and Property Line Adjustments.
(Ord. 08-06 § 3, 2008)
§ 3.5.100 Purpose.
The city recognizes that certain significant historic resources located within its boundaries contribute to the unique character of the community and are irreplaceable, and as such, merit preservation. This chapter establishes an historic landmark commission; a program for the identification, evaluation, and designation of historic resources as landmarks; and a process for assisting in the perpetuation of these resources through review of alteration, moving or demolition of designated historic landmarks which have statewide or national significance.
(Ord. 08-06 § 3, 2008; Ord. 10-02 Exh. A § B, 2010)
§ 3.5.200 Historic landmark commission.
A.
The mayor and city council shall appoint a five-member historic landmark commission (“commission”) with a demonstrated interest, competence, or knowledge in historic preservation to carry out the provisions of this chapter. The membership criteria, term of service, election of officers, number of frequency of meetings, staff support for the commission, and roles and responsibilities of the commission are as provided in the ordinance codified in this title.
B.
A simple majority of the seated members of the commission shall constitute a quorum to conduct official business.
C.
In the event that the historic landmark commission is unable to reach a quorum due to the lack of interested or qualified members, the historic landmark commission shall make recommendations regarding the alteration, moving or demolition of designated historic landmarks and the Silverton planning commission shall make the decision following the Type III process.
D.
Employing the procedures and criteria in SDC § 3.5.300, the commission shall periodically identify, evaluate, and re-evaluate the historic resources of the city and maintain an accurate Historic Resources Inventory.
E.
Employing the procedures and criteria in SDC § 3.5.500, the commission shall periodically revise the designated landmarks register of the city by adding or deleting properties.
F.
Employing the procedures and criteria in SDC §§ 3.5.500 and 3.5.700, the commission shall review and act upon applications for the alteration, relocation, or demolition of properties listed on the Designated Landmarks Register.
G.
The commission shall advise and make policy recommendations to the Silverton city council on matters relating to historic preservation.
H.
Nothing in the above section shall conflict or supersede with the duties and responsibilities assigned to the Silverton planning commission.
(Ord. 08-06 § 3, 2008; Ord. 10-02 Exh. A § B, 2010)
§ 3.5.300 Historic resources inventory.
A.
The commission shall determine and periodically revise priorities for the identification and evaluation of historic resources.
B.
The commission shall use State Historic Preservation Office standards for evaluating historic resources. The system shall rank surveyed historic resources as historic contributing or nonhistoric contributing, and eligible, potentially eligible, or ineligible for listing on the National Registry of Historic Places. Owners of surveyed properties will be notified of these findings.
C.
Documentation of properties in the Historic Resources Inventory shall be on forms compatible with property survey standards established by the State Historic Preservation Office.
D.
Documentation of properties in the Historic Resources Inventory is an administrative function of the community development department that does not require a land use decision.
E.
Alterations or new construction proposed for a property listed on the Historic Resources Inventory are not subject to the regulations of SDC §§ 3.5.600 and 3.5.700 unless the property is also listed on the National Register of Historic Places.
(Ord. 08-06 § 3, 2008; Ord. 10-02 Exh. A § B, 2010)
§ 3.5.400 Local historic districts.
A.
Any individual or group, including the commission acting on its own initiative, may nominate a defined geographical area as a local historic district by submitting a complete application to the commission.
B.
The historic landmarks commission shall review a request for the creation of a local historic district and make a recommendation to city council for the approval or denial of the proposed district. City council shall establish or abolish a local historic district by the enactment of an ordinance.
C.
Documentation of properties within a proposed local historic district shall be on forms compatible with property survey standards established by the State Historic Preservation Office.
D.
At least 55 percent of properties within a proposed local historic district shall be identified as historic contributing properties using State Historic Preservation standards.
E.
Properties identified as historic contributing within approved local historic districts shall be listed on the Historic Resources Inventory.
F.
The alteration, moving, or demolition of a property located within a designated local historic district is not subject to the regulations of SDC §§ 3.5.600 and 3.5.700 unless that property is also listed on the National Registry of Historic Places.
(Ord. 10-02 Exh. A § B, 2010)
§ 3.5.500 Designated landmarks register.
A.
Properties listed on the National Register of Historic Places, including all properties within National Register Historic District boundaries, shall be automatically listed on the Designated Landmarks Register. As Historic Resources of Statewide or National Significance, all such properties shall be subject to the regulations in SDC §§ 3.5.600 and 3.5.700. Only properties listed on the Designated Landmarks Register shall be eligible for tax incentives and grants administered by the State Historic Preservation Office.
B.
Any individual or group, including the commission acting on its own initiative, may nominate a historic resource for inclusion on or removal from the Designated Landmarks Register by submitting a complete application to the commission. The burden of proof lies with the applicant. No individual property shall be so designated without the written consent of the owner. In the case of multiple ownership, no property shall be so designated if a majority of the owners oppose the designation.
C.
The commission shall establish standards for a complete application. Upon acceptance of a complete application, the commission shall review the application using a Type III procedure under SDC § 4.1.400.
D.
In order to be included or maintained on the Designated Landmarks Register, the commission must find that the historic resource is over 50 years of age or of extraordinary historic importance, and possess sufficient historic integrity, and:
1.
Is associated with events that have made a significant contribution to the broad patterns of local, state, or national history; or
2.
Is associated with the lives of persons, or groups of people, significant in local, state, or national history; or
3.
Embodies the distinctive characteristics of an architectural type, style, period, or method of construction or that represents the work of a master, or that possesses high artistic values, or that represents a significant and distinguishable entity whose components may lack individual distinction; or
4.
Has yielded or is likely to yield information which is important in local, state, or national history.
E.
The commission shall develop findings to support its decisions. These findings shall indicate those elements of a property, including interior landscape, architecture, and archaeological features, that are included in the designation.
(Ord. 08-06 § 3, 2008. Formerly 3.5.400; Ord. 10-02 Exh. A § B, 2010)
§ 3.5.600 Historic design review.
A.
Alterations or new construction located on a property listed on the designated landmarks register are subject to historic design review unless exempted by subsection (B) of this section.
B.
Exempt from Historic Design Review. The following activities shall be exempt from historic design review:
1.
Normal repair and maintenance other than change of facade color where exterior material or color is specifically listed in the National Register nomination as an attribute that contributes to the resource’s historic value;
2.
Changes that do not require a building permit, design review permit, sign permit, or other permit from the city and that will not alter the exterior material of a historic resource;
3.
Changes of exterior paint color unless the exterior color was specifically listed in the National Register of Historic Places nomination as an attribute that contributes to the resource’s historic value; or
4.
Changes in landscaping unless the landscaping is identified in the National Register of Historic Places nomination as an attribute that contributes to the resource’s historic value;
5.
Parking lot landscaping that meets the standards of Chapter 3.2 SDC and does not involve the installation of a wall or fence;
C.
The following activities shall require staff-level historic design review through a Type I (subsections (C)(1) through (4) of this section) or Type II (subsections (C)(5) through (7) of this section) procedure (SDC §§ 4.1.200 and 4.1.300), as applicable:
1.
Exterior alterations or renovations to elevation(s) facing an interior or rear property line or that are not otherwise visible from the adjacent public right(s)-of-way.
2.
Additions to the building that are not visible from the public right(s)-of-way and do not change the building footprint, height, volume or massing as seen from the adjacent public right(s)-of-way.
3.
Restoration of historic features using materials and techniques that are similar to those used in the original construction or that will substantially replicate the original when such materials or techniques are not available.
4.
In-kind replacement of doors, windows, siding and other architectural features that are visible from the adjacent public right(s)-of-way.
5.
Uncovered or covered rear deck additions not visible from the adjacent public right(s)-of-way.
6.
Construction of a detached accessory structure with 460 square feet or less of floor area when the accessory structure is at least 40 feet from a front property line.
7.
Installation of new or replacement awnings.
D.
The following activities shall require historic design review through a Type III procedure (SDC § 4.1.400). A public hearing before the historic landmark commission is required for:
1.
Exterior alterations, renovations, or additions to elevation(s) facing a public right(s)-of-way or that are visible from the public right(s)-of-way that result in an increase in building footprint, height, volume, or massing.
2.
Construction of a new building(s) or placement of a relocated structure(s) on an historic site.
3.
Restoration of historic features using materials and techniques that are dissimilar to those used in the original construction or that will substantially deviate from the original construction in terms of style, design, or character.
4.
Changes of exterior paint color from a paint color that was specifically listed in the National Register nomination as an attribute that contributes to the resource’s historic value.
5.
Relocation of a historic building.
6.
Public art.
7.
Covered or uncovered rear deck additions that are visible from the adjacent public right(s)-of-way.
8.
Construction of a detached accessory structure with greater than 460 square feet of area or when the accessory structure is less than 40 feet from a front property line.
E.
At a minimum an application for historic design review shall include:
1.
Materials as required for design review under Chapter 4.2 SDC.
2.
Documentation from the historic resources inventory.
3.
Narrative description of proposed alteration to the historic resource.
4.
Other materials as deemed necessary by the community development director to assist in historic design review.
F.
Upon acceptance of a complete application staff shall process the request through a Type I or Type II procedure (SDC §§ 4.1.200 or 4.1.300) or schedule a public hearing before the landmark commission pursuant to SDC § 4.1.400.
G.
Where an application requires design review under Chapter 4.2 SDC (e.g., modification to a nonhistoric parking lot) and historic design review by the landmark commission (e.g., modification to an historic structure), the commission may serve as the reviewing body for both requests. Alternatively, separate hearings before the planning commission and landmark commission may be required, with the landmark commission’s review limited to historic elements of the project. The community development director shall have discretion in determining the applicable reviewing body based on the size and scope of the project, and consistent with the criteria in Chapters 3.5 and 4.2 SDC.
H.
The burden of proof lies with the applicant. Applications for historic design review may be approved, approved with conditions, or denied. Conditions imposed by the landmarks commission are binding on all permits issued pursuant to city codes.
I.
In general, a proposed alteration or new construction shall either:
1.
Cause the property listed on the designated landmarks register to more closely approximate the original historic design or style, appearance, or material composition of the historic resource; or
2.
Be compatible with the historic characteristics of the property listed on the designated landmarks register based on a consideration of the historic design or style, appearance, or material composition of the historic resource.
J.
In order to approve historic design review applications, the reviewing body shall consider the following criteria:
1.
Facades. Characteristic architectural features, such as balconies, porches, bay windows, dormers, or trim details on main facades shall be retained, restored, or designed to complement the primary structure and any existing surrounding comparable historic resources. Particular attention should be paid to those facades facing street rights-of-way. Architectural elements inconsistent with the property’s existing building design or style shall be avoided.
2.
Building Materials. Building materials shall be reflective of, and complementary to, those found on the existing Designated Landmarks Register property and existing surrounding comparable historic resources. Siding materials of vertical board, plywood, cement stucco, aluminum, exposed concrete block, and vinyl shall be avoided unless documented as being consistent with the original design or style of the property.
3.
Architectural Details. Retention and repair of existing character-defining elements of a structure, such as molding or trim, brackets, columns, cladding, ornamentation, and other finishing details and their design or style, materials, and dimensions, shall be considered by the property owner prior to replacement. Replacements for existing architectural elements or proposed new architectural elements shall be consistent with the resource’s design or style. If any previously existing architectural elements are restored, such features shall be consistent with the documented building design or style. Conjectural architectural details shall not be applied.
4.
Scale and Proportion. The size and proportions of the alteration or new construction shall be compatible with existing structures on the site, if proposed to remain, and with any surrounding comparable structures. Additions or new construction shall generally be smaller than the impacted designated historic resource, if proposed to remain. In rare instances where an addition or new construction is proposed to be larger than the original historic resource, it shall be designed such that no single element is visually larger than the original resource, if proposed to remain, or any existing surrounding comparable historic resources.
5.
Height. To the extent possible, the height of the alteration or new construction shall not exceed that of the existing historic resource, if proposed to remain, and any existing surrounding comparable historic resources. However, second story additions are allowed, provided they are consistent with the height standards of the underlying zoning designation and other chapters of this code, and provided they are consistent with the other review criteria contained herein.
6.
Roof Shape. New roofs shall match the pitch and shape of the original historic structure if proposed to remain, or any existing surrounding compatible historic resources.
7.
Pattern of Window and Door Openings. To the extent possible window and door openings shall be compatible with the original features of the existing historic resource, if proposed to remain, in form (size, proportion, detailing), materials, type, pattern, and placement of openings.
8.
Building Orientation. Building orientation shall be compatible with existing development patterns on the Designated Landmarks Register property, if proposed to remain, and any existing surrounding comparable historic properties. In general, alteration or new construction shall be sited so that the impact to primary facade(s) of the historic structure proposed to remain is minimized.
9.
Site Development. To the extent practicable, given other applicable development standards, such as standards in this code for building coverage, setbacks, landscaping, sidewalk and street tree locations, the alteration or new construction shall maintain existing site development patterns, if proposed to remain.
10.
Accessory Development/Structures. Accessory structures development such as exterior lighting, walls, fences, awnings, and landscaping that are associated with an alteration or new construction shall be visually compatible with the architectural design or style of the existing Designated Landmarks Register property, if proposed to remain, and any surrounding comparable historic properties.
11.
Garages. Garages, including doors, shall be compatible with the site’s primary structure, if proposed to remain, based on factors that include design or style, roof pitch and shape, architectural details, location and orientation, and building materials. The design or style of alteration or new construction involving an existing or new garage, visible from public rights-of-way or private street rights-of-way, shall also be compatible with the design or style of other surrounding comparable historic properties.
12.
Chemical or Physical Treatments. Chemical or physical treatments, if appropriate, shall be undertaken using the gentlest means possible. Treatments that cause damage to historic materials shall not be used.
13.
Differentiation. An alteration or new construction shall be differentiated from the portions of the site’s existing historic resource. However, it shall also be compatible with the historic resource’s significant materials, design or style elements, features, size, scale, proportion, and massing. Therefore, the differentiation may be subtle and may be accomplished with variations in wall or roof alignment, offsets, roof pitch, or roof height. Alternatively, differentiation may be accomplished by a visual change in surface, such as a molding strip or other element that acts as an interface between the original resource and the alteration or new construction.
(Ord. 08-06 § 3, 2008. Formerly 3.5.500; Ord. 10-02 Exh. A § B, 2010)
§ 3.5.700 Historic relocations and demolitions.
A.
Applications for the relocation or demolition of a designated landmark or historic resource of statewide significance shall be considered in a public hearing by the landmark commission following a Type III procedure (SDC § 4.1.400). In order for the commission to approve the relocation or demolition, it must find that:
1.
No prudent and feasible alternative exists; or
2.
The designated property is deteriorated beyond repair; or
3.
The value to the community of the proposed use of the property outweighs the value of retaining the designated landmark or historic resource of statewide significance.
B.
At the hearing for an application to relocate or demolish a designated landmark or historic resource of statewide significance, the commission may, in the interest of exploring reasonable alternatives, delay issuance of a demolition permit for up to 90 days from the date of the hearing. If, 10 days prior to the expiration of the delay period, the commission finds that there are still reasonable alternatives to explore, it may apply to the Silverton city council for permission to continue the delay for an additional period of up to 90 days.
C.
In approving an application for the demolition of a designated landmark or historic resource of statewide significance, the commission may impose the following conditions:
1.
Photographic, video, or drawn recordation of the property to be demolished; and/or
2.
Salvage and creation of significant elements; and/or
3.
Other reasonable mitigation measures.
(Ord. 08-06 § 3, 2008. Formerly 3.5.600; Ord. 10-02 Exh. A § B, 2010)
§ 3.5.800 Exclusions.
A.
No provision of this title shall be construed to prevent the ordinary or emergency repair or maintenance of a designated landmark or historic resource of statewide significance, when such action does not involve a change in design, materials, or appearance.
B.
No provision in this title shall be construed to prevent the alteration, demolition, or relocation of a designated landmark or historic resource of statewide significance, when the building official certifies that such action is required for public safety.
(Ord. 08-06 § 3, 2008. Formerly 3.5.700; Ord. 10-02 Exh. A § B, 2010)
§ 3.5.900 Appeals.
A.
Appeals of historic design review decisions by staff are referred to the landmark commission for a public hearing under SDC § 4.1.300(G).
B.
Decisions of the landmark commission can be appealed to the Silverton city council, as provided under SDC § 4.1.300(G). Decisions of the Silverton city council can be appealed to the Land Use Board of Appeals.
(Ord. 08-06 § 3, 2008. Formerly 3.5.800; Ord. 10-02 Exh. A § B, 2010)
§ 3.6.100 Purpose.
The purpose of this chapter is to promote community health, safety, and welfare by protecting the trees in Silverton’s urban forest and setting development standards, for their planting, care, and removal. Together, elements of the natural and built environment contribute to the visual quality, environmental health, and character of the community. Trees provide climate control through shading during summer months and wind screening during winter. The collective aboveground biomass of trees store and isolate carbon allowing removal of pollution. In addition, their leaves and stems help avoid water runoff. Trees and other plants can also buffer pedestrians from traffic. Walls, fences, trees, and other landscape materials also provide vital screening and buffering between land uses. Landscaped areas help to control surface water drainage and can improve water quality, as compared to paved or built surfaces. This chapter regulates the removal, protection, and planting of trees throughout the development process to encourage development to incorporate existing trees, particularly high quality or larger trees and groves, into the site design, to retain sufficient space to plant new trees, and to ensure suitable tree replacement when trees are removed. It is the intent of these provisions to lessen the impact of tree removal and to ensure mitigation when tree preservation standards are not met.
(Ord. 25-09 § 7, 2025)
§ 3.6.110 Where this chapter applies.
This chapter only applies to development properties within Silverton’s city limits. Trees within public rights-of-way that are managed by the state of Oregon are exempt from the regulations of this chapter. Trees located on lands or within utility corridor easements that are owned by state or federal agencies are also exempt from the regulations in this chapter. However, these trees may be subject to other city regulations or intergovernmental agreements. Furthermore, the city retains summary abatement authority for nuisances posing an immediate threat to public safety.
(Ord. 25-09 § 7, 2025)
§ 3.6.120 Definitions.
The following definitions will apply to the terminology used in this chapter. If a definition is not listed in this chapter, the definition in Chapter 1.5 SDC will apply. Where definitions are not provided in this chapter or Chapter 1.5 SDC, their normal dictionary meaning will apply:
“Arboriculture”
means the practice and study of the care of trees and other woody plants in the landscape.
Arborist.
See “Certified arborist.”
“Caliper”
is the standard trunk diameter measurement for trees taken six inches above grade for up to and including four-inch caliper size and 12 inches above grade for a large tree. This may be contrasted with DBH which is always measured at four and one-half feet above grade.
“Canopy tree”
is a deciduous tree with a mature height of more than 25 feet. The following sources are approved for determining mature height:
1.
Silverton tree and tree crown area reference list (Figure 3.6.170);
2.
https://landscapeplants.oregonstate.edu/node/2163 (Oregon State University College of Agricultural Sciences – Department of Horticulture, Landscape Plants);
3.
The Tree Book by Michael A. Dirr and Keith S. Warren;
4.
Manual of Woody Landscape Plants by Michael A. Dirr;
5.
When these sources do not list the species or variety in question other published sources are acceptable.
“Certified arborist”
means a person who has a current and valid designation of “ISA Certified Arborist” by the International Society of Arboriculture, demonstrating specialized knowledge, experience, and training relating to arboriculture.
“City”
means the city of Silverton.
“City manager”
means the city manager or the city manager’s authorized representative or designee.
“City trees”
means trees located on property designated as city property, including public parks, and trees located in public right-of-way not defined as street right-of-way.
“Community development director”
means the community development director or the director’s designee.
“Conservation”
means maintaining significant native trees and vegetation in the landscapes of development and protecting vegetation in sensitive natural areas. The use of mature, native vegetation within developments is a preferred alternative to removal of vegetation followed by replanting. Mature landscaping provides summer shade and wind breaks, controls erosion, and allows for water conservation due to larger plants having established root systems.
“Critical root protection zone”
means the distance extending out from and surrounding a tree trunk representing the essential area of the roots that must be maintained for the tree’s survival. The critical root zone distance is calculated by multiplying the diameter of the tree, in inches, measured at four and one-half feet above the mean ground level, DBH, by 12 or the dripline of the tree, whichever is larger. For example, a tree with a diameter of two inches would have a critical root zone of 24 inches, which is two times 12 all around the tree.
“Crown”
means area of the tree above the ground, measured in mass, volume, or area extending from the trunk and including the branches, stems, leaves, and reproductive structures.
“Crown area”
means the average area in square feet that the tree crown covers (Figure 3.6.120-1).
“Cultivated”
means trees and plants grown for their ornamental traits or other ecological and sociological benefits. They may include wild plants and native species.
Figure 3.6.120-01: Measuring Crown Area  |
“Cutting”
means the felling or removal of a tree, or any procedure that results in the death or substantial destruction of a tree. Cutting does not include normal trimming or pruning but does include topping of trees.
“DBH”
means the diameter at breast height. See “Diameter at breast height.”
“Dangerous tree”
is a tree which in the professional assessment of a certified arborist has a strong likelihood of causing a hazard to life or property.
“Dead tree”
means a tree that is dead or has been damaged beyond repair or where not enough live tissue, green leaves, limbs, or branches exist to sustain life.
“Deciduous tree”
means trees which shed or lose foliage at the end of the growing season.
“Development”
means all improvements on a site, including buildings, other structures, parking and loading areas, landscaping, paved or graveled areas, and areas devoted to exterior display, storage, or activities. Development includes improved open areas such as plazas and walkways but does not include natural geologic forms or unimproved land.
“Development impact area”
is the area on a site affected by proposed site improvements, including buildings, structures, parking and loading areas, landscaping, and paved or graveled areas. The “development impact area” also refers to areas devoted to storage of materials, or construction activities such as grading, filling, trenching, or other excavation necessary to install utilities or access.
“Development review”
is a generic term meaning any type of review undertaken to ensure compliance with this code.
“Diameter at breast height” or “DBH”
means the measurement of trees as measured at a height four and one-half feet above the mean ground level at the base of the tree (Figure 3.6.120-02). The DBH may be determined by measuring the circumference of the tree trunk four and one-half feet above the mean ground level at the base of the tree and dividing by 3.14. Trees existing on slopes are measured at the mean ground level at the base of the tree (Figure 3.6.120-02). When the trunk branches or splits less than four and one-half feet from the ground, measure the smallest circumference below the lowest branch and divide by 3.14 (Figure 3.6.120-02). For multi-stemmed trees, the size is determined by measuring all the trunks, and then adding the total diameter of the largest trunk to one-half the diameter of each additional trunk. A multi-stemmed tree has trunks that are connected above the ground and does not include individual trees growing close together or from a common root stock that do not have trunks connected above the ground (Figure 3.6.120-02).
Figure 3.6.120-02: Measuring Diameter at Breast Height  |
Figure 3.6.120-03: Distinguishing Circumference and Diameter  |
“Dripline”
means an imaginary line around a tree or shrub at a distance from the trunk equivalent to the canopy (leaf and branch) spread.
“Dying tree”
means a tree that is diseased, infested by insects, deteriorating, or rotting, as determined by a certified arborist, and that cannot be saved by standard horticultural or arboricultural practices, or a tree that must be removed to prevent the spread of infestation or disease to other trees.
“Evergreen”
means trees and plants that retain their foliage throughout the year.
“Fee schedule”
is the schedule of city fees and charges adopted by city council.
“Grove”
means a contiguous and clearly demarcated group of eight or more trees (or three or more Oregon white oaks) growing closely together in a manner that creates a distinct and contiguous canopy. All trees in the grove must be greater than significant size DBH for their species as listed in this chapter. They may belong to the same species or a mixture of species covering an area of less than one-eighth of an acre, or 5,445 square feet.
“Heritage grove”
is a grove that has been formally recognized by the historic landmarks commission and the city for its size, age, species, and/or historical, habitat, or horticultural significance.
“Heritage tree”
is a tree designated as a historic landmark tree, a historic tree, or a heritage tree by the historic landmarks commission and the city for its size, age, species, and/or historical, habitat, or horticultural significance.
“Infected”
means any appearance of a disease on trees or plants that may be a menace to horticultural or farm crops.
“Infested”
means when the adult, egg, larvae or pupae of an insect or other plant pest is found in such numbers as, in the opinion of the city, to be a menace to horticultural or farm crops.
“Invasive species”
means nonnative organisms that cause economic or environmental harm and can spread to new areas of the city. “Invasive species” does not include humans, domestic livestock, or non-harmful exotic organisms.
“ISA”
means the International Society of Arboriculture.
“ISA best management practices”
means the guidelines established by ISA for arboricultural practices for use by arborists, tree workers, and the people who employ their services.
“Large tree”
is a tree of a species which normally reaches a height of 40 feet or more upon maturity.
“Major pruning”
means removal of 20 percent or more of the live crown or pruning cuts removing branches with diameter greater than 40 percent of tree DBH at the point one inch above where the branch attaches to the trunk, or six inches, whichever is greater, or removal of or injury to 15 percent or more of the root system during any 12-month period.
“Mature trees”
are trees that are close to their full height and crown size, these dimensions being determined by species and site factors.
“Multi-stemmed tree”
is a tree having two or more main trunks arising from the root collar or from the main trunk. Their size is determined by measuring all the trunks, and then adding the total diameter of the largest trunk to one-half the diameter of each additional trunk if the tree is classified as significant.
“Owner”
means any person who owns land, or a lessee, agent, employee, or other person acting on behalf of the owner with the owner’s written consent.
“Person”
means any individual, partnership, co-partnership, firm, company, corporation, association, joint stock company, trust, estate, governmental entity, or any other legal entity, or their legal representatives, agents, or assigns.
“Pest”
means a disease, microscopic organism, insect, nematode, arthropod, parasite, or a noxious weed as defined in ORS 569.175 (definitions for ORS 569.175 to 569.195), capable of having a significant adverse effect on the environmental quality of this state or of causing a significant level of economic damage in this state, including but not limited to damage to agricultural, horticultural or forest plants, crops, commodities or products.
“Plant”
means to plant, to put or set a growing plant, whether with roots or a piece of a plant that has the capacity to grow roots, into the ground so that it can grow.
“Planter strip”
means a landscaped area for city-approved street trees and other plantings within the public right-of-way, usually a continuous planter area between the street and a sidewalk. See also “Tree well.”
“Public agency”
means any public agency or public utility as defined in ORS 757.005, or a drainage district organized under ORS Chapter 547.
“Public right-of-way”
means land dedication or easement conveyance to the city or other public entity for public use; typically for streets, utilities, parkland and/or similar facilities. Permanent structures, objects and buildings are not allowed to project over or encroach into public rights-of-way, except as allowed by the city for landscaping and trees.
“Public tree”
means a tree on land owned or maintained by the city.
“Public works director”
means the public works director or the director’s designee.
“Remove or removal”
means to fell or sever a tree or the intentional use of any procedure, the natural result of which is to cause the death or substantial destruction of the tree. Removal does not in any context include normal trimming of trees.
“Significant tree”
means:
1.
Any tree meeting the threshold size standards in SDC § 3.6.150(A).
“Small tree”
is a tree species which normally does not reach a height that exceeds 25 feet upon reaching maturity.
“Staging”
means a designated area for the storage of equipment and vehicles, stockpiles, waste bins, and other construction-related materials during a construction project. Any construction trailers are to be included in the construction staging area. In some cases, more than one staging area may be established on site.
“Stormwater runoff”
is any surface water runoff or runoff in channels which results directly either from a rainstorm or from the melting of snow. The U.S. EPA has declared pollution from stormwater runoff to be the nation’s largest source of water quality problems.
“Street tree”
means a city-approved tree planted in a planter strip or tree well in a city street right-of-way. When any portion of the trunk of a tree crosses a public right-of-way line at ground level, it is considered a street tree.
“Street tree and tree crown area reference list”
includes tree species approved by the city for planting within the right-of-way and tree crown calculations for residential development.
“Sustainable and urban tree advisory board”
advises the city council and/or the planning commission on programs, practices and decision-making involving all aspects of urban forestry.
“Topping”
means the cutting back of limbs or trunks within the tree’s crown to buds, stubs, or lateral branches not large enough to assume the terminal role. It is an inappropriate pruning practice used to reduce tree height by cutting to a predetermined crown limit without regard to tree health or structural integrity. Topping does not include acceptable pruning practices as described in the American National Standards Institute (ANSI) “A300 Pruning Standards” and companion “Best Management Practices for Tree Pruning” published by the International Society of Arboriculture, such as crown reduction, utility pruning, or crown cleaning to remove a safety hazard, dead or diseased material. Topping is considered “removal.”
“Tree”
means a self-supporting, perennial woody plant characterized by one main trunk or in some cases multiple trunks, and one main canopy of leaves, usually growing to a height of 15 feet or higher.
“Tree canopy”
means the ground area that, when viewed from above the crown of one or more trees, is mostly covered by the tree(s). For deciduous trees, canopy area is based on the time of year when foliage is present.
“Tree circumference” (see DBH)
means the distance measured around the trunk of a tree at four and one-half feet above the mean ground level from the base of the trunk. For multi-stemmed trees, the size is determined by measuring all the trunks, and then adding the total diameter of the largest trunk to one-half the diameter of each additional trunk.
“Tree contractor”
means a person licensed to complete tree servicing work by the state of Oregon Construction Contractors Board (CCB).
“Tree fund”
means the tree fund as created by this chapter.
“Tree well”
means a planter area cut out of a sidewalk within the street furnishing zone, planted with a street tree and including ground cover or a grate cover; typically used in commercial districts where on-street parking or pedestrian traffic makes the use of a planter strip impracticable.
“Trimming”
is the selective removal of plant parts to meet specific goals and objectives, using best practices as set forth by American National Standards Institute (ANSI) A300 Standards.
“Urban forest”
means the trees and vegetation that exist within the city.
“Urban heat islands”
are metropolitan places where buildings and pavement cause the area to be hotter than outlying areas, with impacts felt most during summer months. Paved roads, parking lots, and buildings absorb and retain heat during the day and radiate that heat back into the surrounding air. “Utility” is a public utility, business, or organization that supplies energy, gas, heat, steam, water, communications, or other services through or associated with telephone lines, cable service, and other telecommunication technologies, sewage disposal and treatment, and other operations for public service.
“Wild”
is an endemic species, or species native to the Silverton area of the Willamette Valley ecoregion. It is a self-sown (grown from a non-human-planted seed) or self-cloning (by root pieces, suckers, branch layer, or sprout) plant.
“Woodland”
is an area of contiguous wooded vegetation where trees are at a density of at least one significant DBH tree per 325 square feet of land where the branches and leaves form a continuous canopy. A woodland shall include areas with continuous canopy of trees over an area of at least 20,000 square feet and with any dimension being not less than 35 feet. A woodland may be delineated through an aerial photograph or a ground survey. A woodland shall include both understory and protected trees.
(Ord. 25-09 § 7, 2025)
§ 3.6.130 Administration.
A.
Authority. The city of Silverton shall have control of all street trees, shrubs, and other plantings now or hereafter in any street, park, public right-of-way or easement, or other public place within the city, and shall have the power to plant, care for, maintain, remove, replace, and require the care of, maintenance of, removal, and replacement of such trees, shrubs and other plantings.
B.
Public Trees. The public works director is responsible for the implementation and enforcement of public trees and shall have jurisdiction over all street trees and city trees, including the planting, removal, care, maintenance, and protection thereof.
C.
Private Trees. The community development director is responsible for the implementation and enforcement of the provisions in this chapter.
D.
Advising Body. The sustainable and urban tree advisory board advises the city council and/or the planning commission on programs, practices and decision-making involving all aspects of urban forestry. Duties and responsibilities include the following:
1.
Study, investigate and provide advice to the city council and/or the planning commission on the preservation, pruning, planting, replanting, removal, or disposition of the urban forest.
2.
Provide advice to the city council and/or the planning commission on policy and regulatory issues involving trees, including climate adaptation and mitigation efforts.
3.
Provide outreach and education to the community on tree-related issues and concerns.
4.
Provide recommendations to the city council on the allocation of funds from the tree fund.
5.
The sustainable and urban tree advisory board, when requested by the city council, will consider, investigate, make findings, report, and make recommendations on any special matter or question coming within the scope of its work.
(Ord. 25-09 § 7, 2025)
§ 3.6.140 Creation of a tree fund.
A.
Establishment. A city tree fund is hereby established for the collection of any funds used for the purpose and intent set forth by this chapter.
B.
Funding Sources. The following funding sources may be allocated to the tree fund:
1.
Tree permit revenue.
2.
Payments received in lieu of required and/or supplemental plantings.
3.
Civil penalties collected pursuant to this chapter.
4.
Agreed-upon restoration payments or settlements in lieu of penalties.
5.
Sale of trees or wood from city property.
6.
Donations and grants for tree purposes.
7.
Other monies allocated by the city council.
C.
Funding Purposes. The city will use the tree fund for the following purposes:
1.
Expanding, maintaining, and preserving the urban forest within the city;
2.
Planting and maintaining trees within the city;
3.
Supporting public education related to urban forestry;
4.
Assessing urban forest canopy coverage; or
5.
Any other purpose related to trees, wood-land protection, and enhancement as determined by the city council.
(Ord. 25-09 § 7, 2025)
§ 3.6.150 Tree preservation and planting.
Intent. Trees provide important ecological and social services to the residents of Silverton, but it takes years and sometimes decades to reach a size that makes a substantial contribution. Each tree species varies in the size it may reach at maturity. The size of a tree is not the only measure of its contribution to society or its ecological impact.
A.
Significant Trees. The significant tree designations set forth in this subsection establish a threshold trunk size, measured in DBH, for various tree species. A significant tree is defined by the DBH as set forth below.
1.
Significant DBH. Figure 3.6.150-01 gives the DBH at which the city considers each tree species significant. Trees with DBH at or greater than that listed DBH are significant and must be treated as such when establishing their status and protection according to this chapter.
2.
In order to establish the significance of a tree within city limits, an applicant shall complete the following, in the order listed below:
a.
Identify trees four inches or greater in DBH that are located on the development property.
b.
Determine the species identity of such trees.
c.
Measure the circumference of such trees at DBH. Divide the circumference in inches by 3.14 to determine the product, inches DBH.
i.
Example: species Abies grandis
circumference measured at DBH = 37 inches
37 3.14 = 11.78 inches DBH
Species Abies grandis must be 18 inches DBH or more to be significant, therefore this tree is not significant
3.
Mature Crown Area. To calculate mature crown area square half of the mature width then multiply by 3.14. For instance a Grand Fir has a width at maturity of 30 feet, therefore 15 feet times 15 feet times 3.14 equals 706.5 square feet.
4.
Minimum Landscape Standards. Significant trees are protected as set forth in subsections below. An applicant may credit significant trees protected in accordance with this chapter toward meeting the minimum landscape area standards in Chapter 3.2 SDC.
Figure 3.6.150-01: Significant Tree DBH | ||
|---|---|---|
Latin Name | Common Name | Inches DBH When Species Becomes Significant |
Abies grandis | Grand Fir | 18 |
Acer circinatum | Vine Maple | 6 |
Acer macrophyllum | Bigleaf Maple | 12 |
Alnus rubra | Red Alder | 10 |
Arbutus menziesii | Pacific Madrone | 8 |
Calocedrus decurrens | Incense Cedar | 10 |
Chamaecyparis lawsoniana | Port Orford Cedar | 10 |
Cornus nuttalii | Pacific Dogwood | 4 |
Crataegus douglasii | Douglas Haw | 4 |
Crataegus gaylussacia | Klamath Haw | 4 |
Fraxinus latifolia | Oregon Ash | 6 |
Malus fusca | Oregon Crabapple | 4 |
Pinus monticola | Western White Pine | 22 |
Pinus ponderosa | Willamette Valley Ponderosa Pine | 15 |
Populus trichocarpa | Black Cottonwood | 24 |
Prunus emarginata | Bitter Cherry | 6 |
Pseudotsuga menziesii | Douglas Fir | 24 |
Quercus garryana | Oregon White Oak | 6 |
Salix scouleri | Scouler’s Willow | 4 |
Taxus brevifolia | Pacific Yew | 4 |
Thuja plicata | Western Red Cedar | 22 |
Tsuga heterophylla | Western Hemlock | 20 |
Any noninvasive tree not listed including nonnative tree species | Generally accepted mature height* x 20% = inches DBH to be significant. Where a range of mature heights are indicated, the taller number shall be used to determine significance. | |
Notes: | |
|---|---|
* | The following sources are approved to establish generally accepted mature height, width, and crown area in the order below: |
1. | Silverton Tree and Tree Crown Area Reference List (Figure 3.6.170) |
2. | https://landscapeplants.oregonstate.edu/node/2163 (Oregon State University College of Agricultural Sciences – Department of Horticulture – Landscape Plants) |
3. | The Tree Book by Michael A. Dirr and Keith S. Warren |
4. | Manual of Woody Landscape Plants by Michael A. Dirr |
5. | When these sources do not list the species or variety in question other published sources are acceptable. |
B.
Heritage Trees. The historic landmarks commission may designate certain trees or groups of trees as “heritage trees” within the city; provided, that the landowner(s) of record upon which the tree or grove is located consents. The consent of a property owner will bind all successors, heirs, and assigns. The purpose of the heritage tree or heritage grove designation is to recognize, foster appreciation of, and protect trees and groves having special importance to the community. The historic landmarks commission shall have the authority to determine whether a tree or grove recommended for consideration qualifies as a heritage tree or grove. Any member of the public, whether a historic landmarks commission member, property owner, or third-party citizen, may nominate trees or groves to the historic landmarks commission. Once a tree or grove is designated as a heritage tree or heritage grove, it will remain so unless it becomes necessary to classify it as a dangerous tree and be removed as such. Except as otherwise expressly provided in this chapter, heritage trees and groups of heritage trees may not be removed without the express consent of the historic landmarks commission.
C.
Tree Conservation.
1.
Applicability. The purpose of this section is to incorporate trees into the landscapes of development and to protect significant trees and trees in sensitive natural areas. The use of mature, native trees within developments is a preferred alternative to removal of trees and replanting. Mature landscaping provides summer shade and wind breaks, controls erosion, and allows for water conservation due to larger trees having established root systems.
The tree preservation requirements in this subsection apply to the following types of development:
a.
Land divisions;
b.
Design reviews/conditional uses;
c.
Expansion of existing parking lots that results in an increase in paved surfaces;
d.
Conversion of gravel parking lots to paved parking lots.
2.
Protection and Planting Standards.
a.
Tree Canopy Preservation and Planting Standards for Private Property. There is a target tree canopy standard for all land use categories on private property. The target tree canopy shall be met either through preservation of existing trees, replanting of removed trees, or planting new trees where a site did not meet the standard prior to development, as provided in this chapter. Public right-of-way and proposed public right-of-way are not considered part of the development site for the purposes of the canopy coverage calculations. When calculating canopy threshold percentages, all percentage numbers shall be rounded to the nearest whole number. See Chapter 3.2 SDC for street tree planting requirements.
Figure 3.6.150-02: Target Tree Canopy | |
|---|---|
Category of Use | Target Tree Canopy Percentage of Tree Canopy Versus Total Area of Property (ending tree canopy coverage) |
R-1 Single-Family Residential R-5 Low Density Residential | 25 percent |
RM-10 Multiple-Family Residential – 10 RM-20 Multiple-Family Residential – 20 | 25 percent |
Acreage Residential | 40 percent |
Downtown Commercial Fringe, General Commercial | 10 percent |
Industrial Park, Light Industrial | 15 percent |
b.
Tree Preservation on Public Lands. Trees on public lands shall not be damaged or destroyed, except as approved by the city to address an immediate hazard to public safety, and except as otherwise exempted in subsection (C)(8) of this section.
c.
Tree Preservation on Private Property. Tree protection on private property shall follow subsections (C)(2)(c)(i) through (C)(2)(c)(ii) of this section during the development process, as applicable.
i.
Target Tree Canopy. If a development site has a tree canopy coverage of significant trees greater than the standard, trees may be removed provided the standard is still met after removal. The developer may request on-site existing tree removal up to 30 percent below the target tree canopy standard percentage for its use category identified in subsection (C)(2)(a) of this section with mitigation provided per subsection (C)(4) of this section. The developer may request tree removal in excess of the 30 percent below the target tree canopy standard which is a discretionary review by the planning commission following SDC § 4.2.510 and with mitigation provided per subsection (C)(4) of this section.
ii.
If a site does not have a tree canopy coverage of significant trees greater than the standard, the developer may request on-site existing tree removal up to 30 percent of the existing tree canopy with mitigation provided per subsection (C)(4) of this section. The developer may request tree removal in excess of the 30 percent existing tree canopy which is a discretionary review by the planning commission following SDC § 4.2.510 and with mitigation provided per subsection (C)(4) of this section.
d.
Parking Lot Standards. Shade trees shall be evenly distributed and conform to the criteria in Chapter 3.2 SDC, SDC § 3.2.300(E)(1)(a) through (E)(1)(h) and (E)(3). “Evenly distributed” means that the trees are distributed around the parking lot perimeter and between parking bays to provide a partial canopy. At a minimum, one canopy tree per 10 contiguous (side-by-side) parking spaces shall be provided. All parking area planters with trees shall have dimensions of not less than 48 square feet of area, or not less than six feet in width by eight feet in length, to ensure adequate soil, water, and space for healthy plant growth. Such areas shall have irrigation or temporary irrigation to ensure plant survival and success. Parking lot trees may count toward minimum canopy coverage requirements per Figure 3.6.150-02.
e.
Oregon White Oak. Notwithstanding anything to the contrary in this section, it is unlawful to remove any significant Quercus garryana (Oregon white oak) tree within the city limits without first making application to the city and obtaining a permit – except as otherwise exempted in subsection (C)(8) of this section.
f.
Any significant Oregon white oak which is removed shall be replaced in accordance with subsection (C)(4)(a) of this section, and an additional Oregon white oak removal fee per SDC § 3.6.190 shall also apply to the required mitigation.
g.
When the trunk of a tree crosses a property line at ground level it is considered an on-site tree except when the trunk crosses a public right-of-way line at ground level, it is considered a street tree. Public right-of-way will be considered off-site for the purpose of this section.
h.
Any tree saved and protected through a land division application must be identified and labeled on the site plan. Prior to the final plat being signed, a sign shall be posted at each tree or grove stating the trees are required to remain and be protected through development and include penalty fees for violation. See requirements for tree protection during construction in this chapter, SDC § 3.6.200. Signs shall be weatherproof and installation shall not cause any damage to the tree.
3.
Credits.
a.
Significant Trees. Significant healthy trees with DBH of more than 25 percent greater than significant for their species shall receive additional canopy credits over their existing tree crown area which shall be factored into the target tree canopy percentage calculations as defined in Figure 3.6.150-03 below.
Figure 3.6.150-03: Canopy Credits for Trees Greater Than Significant | |
|---|---|
Percent DBH Is Greater Than Significant for the Species | Available Canopy Credits |
25% to 49% | 1.25 |
50% to 74% | 1.50 |
75% or greater | 1.75 |
b.
The following table shall be used when calculating the target tree canopy percentage for significant trees with 25 percent or less than DBH than significant for their species and for trees that are to be planted to meet the target tree canopy:
Figure 3.6.150-04: Tree Planting Standards | ||
|---|---|---|
Tree Location | Existing Trees | Newly Planted Trees |
On-Site Trees (Trees located within the tax lot) | 100% of the existing or future mature crown area, whichever is greater *Significant tree credit for large DBH trees – see SDC § 3.6.190, Fee schedule* | 65% of the future mature crown area |
Off-Site Trees (Street trees within the adjacent ROW) | 50% of the existing or future mature crown area, whichever is greater | 50% of the future mature crown area |
c.
In cases where a portion of the crown area of on-site trees extends off site, the entire crown area is eligible for credit towards the tree canopy requirements. In cases where a portion of the crown area of off-site trees on private property extends on site, the crown area is not eligible for credit towards the tree canopy requirements.
d.
If trees die or are removed within three years for which credits were issued, those trees must be replaced or mitigated per this chapter.
4.
Mitigation Required.
a.
Tree Replacement. Where removal of significant trees is approved below the target tree canopy, and such removal or damage is not otherwise exempted in subsection (C)(8) of this section, the city shall require mitigation and the applicant shall submit a tree planting plan that demonstrates the target tree canopy will be met utilizing the tree planting standards in Figure 2.6.150-4. Where mitigation is approved in excess of the 30 percent below the target canopy, in addition to the plan that demonstrates meeting the target tree canopy, above, the canopy removal in excess of the 30 percent shall be mitigated at double the amount in canopy square feet.
i.
Mitigation and canopy replacement shall be proportionate to the loss of significant trees as described above. Where complete mitigation on site is not practical due to the amount of trees required for mitigation resulting in a target tree canopy of more than 50 percent above the target, the city shall accept an in-lieu fee for mitigation (see SDC § 3.6.190).
5.
Application Requirements. For applications listed in subsection (C)(1) of this section an analysis must demonstrate compliance with the applicable provisions of this chapter. Professionals such as ISA certified arborists, engineers, landscape architects, soil scientists, and surveyors may assist as needed in preparing the required information. The minimum submittal requirements include an inventory of existing trees on site, a tree preservation plan, and a tree planting plan. If multiple construction applications are required for a development proposal, including demolitions and subsequent construction, the same plans shall be included with each application.
a.
Existing Tree Inventory Requirements.
i.
Survey the locations of all trees at least four-inch DBH that are on site, within abutting public rights-of-way, and on abutting sites with root protection zones that extend into the site. The locations and information for trees on abutting sites may be estimated. All invasive trees, regardless of size, are to be located.
ii.
Number each tree for identification on the plans.
iii.
Identify the common name and scientific name of each tree.
iv.
Measure and provide the DBH of each tree in inches according to accepted ISA standards.
v.
Measure the approximate average crown radius of each tree in feet.
vi.
Provide the crown area of each tree using the formula: (crown radius)2 x π.
vii.
Identify if the tree is significant per Figure 3.6.150-01.
viii.
Identify if the tree is invasive per the Oregon Noxious Weed List or Silverton Invasive and Potential Nuisance Tree list, Figure 3.6.150-06.
ix.
Identify if the tree is a heritage tree as defined in subsection (B) of this section.
x.
Identify trees that are dead or in severe decline.
xi.
Identify whether the tree is proposed for removal or retained.
xii.
Organize the tree inventory information in a table.
b.
Tree Preservation Plan Requirements.
i.
Provide a site plan drawn to scale.
ii.
Include the existing tree locations and corresponding tree numbers from the tree inventory.
iii.
Clearly differentiate between significant, invasive and heritage trees through symbols or other methods.
iv.
Identify the following site disturbances:
(A)
Demolition;
(B)
Tree removal;
(C)
Staging, storage, and construction access;
(D)
Grading and filling;
(E)
Paving;
(F)
Construction of structures, foundations, and walls;
(G)
Utility construction;
(H)
Trenching and boring;
(I)
Excavation;
(J)
Any other demolition or construction activities that could result in ground disturbances and/or tree damage.
v.
Locate tree and soil protection fencing to scale.
vi.
Locate soil compaction prevention methods to scale.
vii.
Include tree protection specifications from the arborist report on the plans including a detail and description of tree protection fencing and signage.
viii.
The elements of the tree preservation plan may be included on multiple plan sheets for clarity.
ix.
The final approved set of construction drawings must include the tree preservation plan to ensure contractors, inspectors, and other professionals have access to the information.
c.
Tree Planting Plan.
i.
Provide a site plan drawn to scale.
ii.
Include the existing trees to be retained and their crown areas to scale.
iii.
Include the trees to be planted and their mature crown areas to scale based on the street tree and tree crown area reference list. Any trees not listed shall use the following approved sources to establish mature crown in the order listed below:
(A)
https://landscapeplants.oregonst ate.edu/node/2163 (Oregon State University College of Agricultural Sciences – Department of Horticulture – Landscape Plants);
(B)
The Tree Book by Michael A. Dirr and Keith S. Warren;
(C)
Manual of Woody Landscape Plants by Michael A. Dirr;
(D)
When these sources do not list the species or variety in question other published sources are acceptable.
iv.
Include a diagram depicting the tree planting that is consistent with ISA best management practices.
v.
The minimum size of planted trees is one-and-one-half-inch caliper for deciduous trees, five feet tall for evergreens, three feet tall for Quercus garryana, and Arbutus menziesii. Nursery stock must be in good health with the size and quality consistent with ISA best management practices and ANSI Z60.1 standards.
vi.
The species selection and spacing of trees to be planted must be such that it provides for the eventual mature size of the trees. Soil type, soil conditions and other site constraints shall be considered when selecting species for planting.
vii.
Root barriers must be installed according to the manufacturer’s specifications when a tree is planted within five feet of pavement or an underground utility box.
viii.
Where there are overhead high voltage utility lines, the tree species must be from the city approved street tree list with a designation allowing planting under high voltage lines.
ix.
The elements of the tree planting plan may be included on multiple plan sheets for clarity.
x.
The final approved set of construction drawings must include the tree planting plan to ensure contractors, inspectors, and other professionals have access to the information.
xi.
Include a planting timeline for when the trees are to be installed, who will install the trees, and how the planting will be assured if deferred to after the construction phase of the project.
d.
Report.
i.
Provide a written narrative that summarizes the information from the tree inventory, tree preservation plan, and tree planting plan.
ii.
Provide findings and calculations that demonstrate whether the tree preservation and planting standards in subsection (C)(2) of this section have been met.
iii.
If the tree preservation and/or tree planting standards have not been met, provide calculations for the applicable tree mitigation fees as required by subsection (C)(4) of this section.
iv.
If the applicant is seeking a variance to the tree preservation and/or tree planting standards in place of providing mitigation planting or fees, provide findings that demonstrate the proposal provides equivalent or greater environmental benefits as preserving or planting the required tree canopy as required by subsection (C)(9) of this section.
v.
Provide findings that demonstrate compliance with the tree protection standards in SDC § 3.6.200(A).
6.
Construction. All trees on a site that are not otherwise designated and approved by the city for removal shall be protected prior to, during, and after construction in accordance with SDC § 3.6.200(A).
7.
Additional Approval Criteria. When an application is submitted the city may approve the request when the following additional review criteria is met:
a.
Wooded areas along ridges and hilltops will be retained for their scenic and wildlife value in addition to preventing erosion.
b.
Wooded areas along property lines shall be retained at a minimum width of 10 feet to provide buffers from adjacent properties.
8.
Exemptions. The protection standards in this section do not apply to:
a.
Dead or diseased trees. Dead or diseased trees meeting the criteria for “significant trees” may be removed after approval of a Type I land use review.
b.
The removal is necessary to alleviate a dangerous tree posing an imminent threat to the public health or safety or posing an imminent threat to public or private property or prevent an imminent threat of serious environmental degradation.
c.
Tree removal as required by the city or public utility for the installation or maintenance or repair of roads, utilities, or other structure.
9.
Tree Variances. The applicant may seek an adjustment or variance at no cost to the applicant for smaller lot sizes, sidewalk deviations, on-street parking reduction, frontage improvements, reduced setbacks or a reduction in the number of parking spaces to avoid removal of significant trees, provided the applicant also takes measures to preserve the health of the trees.
a.
Review Criteria. The city shall consider the following review criteria and may approve, approve with conditions, or deny a design review adjustment based on the following; the applicant shall bear the burden of proof:
i.
Adjusting the subject code standard(s), i.e., decreasing, increasing, waiving, or making a material substitution, will result in a design that is as good or better than what would likely result under the base standard;
ii.
The adjustment is consistent with the code’s stated intent and is in the public interest.
10.
Invasive and Nuisance Trees. Trees on the Silverton invasive and potential nuisance tree list shall be removed during site development regardless of their size. The planting of species on the Silverton invasive and potential nuisance tree list is prohibited.
11.
Trees Requiring Approval. It is unlawful to plant native or nonnative willow, cottonwood, or poplar trees outside of riparian restoration projects anywhere in the city unless the public works director approves the site as one where the tree roots will not likely interfere with public sewers.
12.
Wild growing, naturally sown or distributed (through normal asexual spread such as stollens or rooted branches) Willamette Valley native Salix and Populus species may persist within city limits. This allowance does not extend to nonnative, ornamental, or exotic species.
13.
Prohibited in Right-of-Way. It is unlawful to plant fruit trees (other than ornamental fruit trees) or nut trees (other than ornamental nut trees) in or on a public right-of-way.
D.
Wetlands and Riparian Overlay District. Trees play a critical role in the ecological function of riparian corridors. The city and residents have strong interest in ensuring the ongoing function of these areas and vested interests in the existing and future trees growing there.
1.
Applicability. The wetland area regulations apply to those areas meeting Division of State Lands criteria for wetland classification. Precise wetland boundaries may vary from those shown on the comprehensive plan map exhibit if on-site inspection and delineation by a recognized authority and/or other city-approved documentation indicate more accurate boundaries. Those more precise boundaries can be identified, mapped, and used for review and development without a change in the comprehensive plan wetlands map exhibit. All developments proposed within a designated wetland area shall be subject to the provisions of conditional use review and the wetland area regulations (per Chapter 2.7 SDC).
2.
Canopy Protection Thresholds. The minimum threshold canopy percentage for each use area is doubled in the riparian overlay district.
3.
Tree Removal and Mitigation. Removal of significant trees in the wetland and riparian overlay district is allowed pursuant to the other sections of this chapter. Tree removals must be mitigated on site whenever possible to maintain tree cover in the corridor pursuant to the other sections of this chapter.
E.
Invasive and Potential Nuisance Trees. The preservation and removal of trees on the Silverton invasive and potential nuisance trees list is governed by the following provisions:
1.
Planting. Planting of any tree on the invasive and potential nuisance trees list is prohibited
2.
Reproduction. It is prohibited to let any plant with a noxious weed designation on the invasive and potential nuisance trees list produce seed, disseminate fruit, or reproduce sexually (via flowers) within the city.
Figure 3.6.150-06: Invasive and Potential Nuisance Trees | |||
|---|---|---|---|
Scientific Name | Common Name | Nuisance | Noxious Weed |
Education and Control | Immediate Action and Eradication | ||
Acer negundo | Box Elder | Yes | |
Acer platanoides | Norway Maple | Yes | |
Acer pseudoplatanus | Sycamore Maple | Yes | |
Acer saccharinum | Silver Maple | Yes | |
Ailanthus altissima | Tree-of-Heaven | Yes | |
Betula pendula | European White Birch | Yes | |
Crataegus monogyna | English Hawthorn | Yes | |
Ilex aquifolium | English Holly | Yes | |
Laburnum watereri | Goldenchain Tree | Yes | |
Paulownia tomentosa | Empress/Princess Tree | Yes | |
Populus | Cottonwoods and Poplars | Yes | |
Prunus avium | Sweet Cherry | Yes | |
Pyrus calleryana, and all cultivars | Callery Pear | Yes | |
Pyrus betulifolia, and all cultivars | Bradford Pear | Yes | |
Robina pseudoacacia | Black Locust | Yes | |
Salix | Willows | Yes | |
Sorbus aucuparia | European Mountain Ash | Yes | |
Ulmus pumila | Siberian Elm | Yes | |
(Ord. 25-09 § 7, 2025)
§ 3.6.170 Street tree and tree crown area reference list.
A.
Mature Crown Area. To calculate mature crown area square half of the mature width then multiply by 3.14. For instance a Grand Fir has a width at maturity of 30 feet, therefore 15 feet times 15 feet times 3.14 equals 707 square feet.
Tree list adopted by resolution.
(Ord. 25-09 § 7, 2025)
§ 3.6.190 Fee schedule.
Adopted in the city’s master fee schedule resolution.
(Ord. 25-09 § 7, 2025)
§ 3.6.200 Technical specifications.
A.
Tree Protection Specifications.
1.
Intent. Tree protection during development helps to reduce the negative impacts of construction. The tree protection regulations keep the foliage crown, branch structure and trunk clear from direct contact and injury by equipment, materials, or disturbances; preserve roots and soil in an intact and noncompacted state; and visibly identify the root protection zone in which no soil disturbance is permitted, and other activities are restricted. The protection of roots and soil where roots dwell is of critical importance during construction activities. Maintaining these protections through development will lessen undesirable consequences that may result from uninformed or careless acts, preserve both trees and property values, and reduce risks associated with damaged or destabilized trees.
2.
Applicability. These standards apply to any tree that is required to be retained on site or in the street during a development activity. Proposed tree protection shall meet the requirements below, except that the city may approve or require alternate protection methods for street or city trees.
3.
Protection Methods. The tree preservation plan shall show that trees retained are adequately protected during construction using the method described below:
a.
Establish a critical root protection zone by using one of the two following methods:
i.
Calculate by multiplying the diameter of the tree, in inches, measured at DBH, four and one-half feet above the mean ground level, by 12. For example, a tree with a diameter of four inches would have a critical root zone of 48 (four times 12 equals 48) inches all around the tree.
ii.
Determine the tree dripline which is an imaginary line around a tree at a distance from the trunk equivalent to the canopy (leaf and branch) spread as illustrated in Figure 3.6.200-01;
b.
Install protection fencing at the critical root zone perimeter before physical development starts and remain in place until final inspection. The fence shall meet one of the following:
i.
A minimum four-foot-high metal chain link or no-climb horse fence.
ii.
Four-foot-high orange construction fence.
iii.
Existing structures and/or existing secured fencing at least three and one-half feet tall can serve as the required protective fencing with city approval;
Figure 3.6.200-01: Tree Dripline Location  |
c.
Signage designating the protection zone and penalties for violations shall be secured in a prominent location on each protection fence and shall remain until construction is complete;
d.
Installation of landscaping is allowed within the root protection zone and is not an encroachment. Any in-ground irrigation systems are considered encroachments;
e.
The following is prohibited within the root protection zone of each tree or outside the limits of the development impact area: ground disturbance or construction activity including vehicle maneuvering or parking, storage of equipment or materials including soil, temporary or permanent stockpiling, proposed buildings, impervious surfaces, underground utilities, excavation, or fill, trenching or other work activities; and
f.
Hand excavation in the root zone will be allowed if approved through the application process with the submittal of an arborist’s report.
4.
Changes to Tree Protection. Changes to tree protection measures during the development may be approved as a revision to a permit provided that the change is not the result of an unauthorized encroachment into a root protection zone, and the applicant demonstrates that the tree protection standards of this section continue to be met. When an unauthorized encroachment has occurred, the city may pursue an enforcement action or other remedy.
5.
Tree Protection Inspections. The city may conduct inspections during project activity to determine compliance with this chapter and confirm that tree protection zones are being maintained and root protection methods are effective. No person may refuse entry or access to a permitted development site to any authorized representative of the city who provides proper credentials and requests entry for the purpose of conducting a tree protection inspection. In addition, no person may obstruct, hamper, or interfere with any such representative while in the process of carrying out their official duties.
6.
Performance Bond. To ensure that the significant trees identified through the development review process will be retained and protected, the review authority may require the developer to post a performance bond in an amount determined by the size of the trees being preserved as shown in the fee schedule (SDC § 3.6.190). The amount of the required performance bond shall be determined by totaling the number of trees being preserved based on size and bonding value in the fee schedule.
B.
Tree Installation and Ongoing Tree Maintenance.
1.
Installation. Plant materials shall be installed to current nursery industry standards and proper arboricultural practices ANZI Z60, and ISA best practices. Plant materials shall be labeled for the inspector and properly supported to ensure long-term survival. Support devices such as guy wires or stakes shall not interfere with vehicular or pedestrian movement.
2.
Timing. All trees required or approved to be planted shall be planted or payment in lieu of planting made prior to the certificate of occupancy, as applicable. However, it is encouraged that planting occurs during the wet months, October through April. Planting of trees may be deferred between May 1st and September 30th upon filing a performance guarantee or other assurance deemed acceptable by the city.
3.
Maintenance. If a tree(s) fails to survive three years after planting, the property owner shall replace them with an equivalent specimen (i.e., deciduous tree replaces deciduous tree, etc.) within six months of their dying or removal, whichever comes first.
a.
Height Requirements. Trees growing in the right-of-way or on private property must be trimmed to maintain a minimum canopy height of eight feet above sidewalks, or 12 feet above streets or alleys.
b.
Trimming – Specifications – Owner Responsibility.
i.
Trees, standing in or upon any public street or alley, or on private grounds, and having branches projecting into the public street or sidewalk, shall be kept trimmed by the owner or owners of the property adjacent to or in front of such trees growing so that:
(A)
The lowest branches shall not be less than a minimum of 12 feet above any surface of the street pavement and shall not be less than 14 feet above the surface of streets designated as state highways.
(B)
The lowest branches shall not be less than a minimum of eight feet above any surface of a sidewalk.
ii.
Newly planted trees may remain untrimmed; provided they do not interfere with street traffic or people using the sidewalk or obstruct the light of any street electric lamp.
(A)
Trimming – Notice to Comply. Whenever the owner or owners, lessees, occupants or persons in charge of private grounds neglect or refuse to trim any tree as provided in this code, the city shall serve upon such owner or owners, lessees, occupants or persons in charge a written notice to trim such tree or trees within 10 days after giving of such notice; failure to do so will be considered in violation of this chapter and subject to the penalties provided in this code. Such notice shall be served upon the owner or owners, lessees, occupants, person in charge, or occupant of the property by posting the same upon such property or near to the trees, to be trimmed.
(B)
Trimming – City to Perform Work When. If the owner or owners, lessees, occupants or persons in charge of the property fail and neglect to trim such trees within 10 days after receiving said notice, the city manager or duly authorized representative may cause any vegetation in or upon any parking strip, street right-of-way or other public place in the city to be trimmed, pruned, or removed.
(C)
Topping. Tree topping is prohibited in Silverton. Topping is destructive and creates situations resulting in tree growth that is compromised and ultimately dangerous and that diminishes the ecological and social benefits provided by the urban forest. In lieu of topping use standard ISA pruning practices such as tree reduction.
C.
Tree Removal Specifications. Trees shall be removed in a manner that will not jeopardize public safety or damage structures including utility lines or services, or adjacent trees. Trees shall be entirely removed.
1.
Completion. A tree will be considered completely removed when reduced to a stump no taller than four and one-half feet. For street tree removals, the city may direct the stump be ground out up to 18 inches below grade.
2.
Woody Debris Disposal. Utilizing urban wood is encouraged. Consider rather than burning or hauling to the landfill using cut trees for durable wood products. In all cases disposal, use, or reuse of wood and woody debris from private trees is at the property owner’s discretion, provided storage of wood does not constitute a public health or safety nuisance. If the city determines that the tree is affected by a pathogen or insect infestation that will likely adversely impact surrounding trees, all portions of the tree shall be removed from the site and properly disposed of at the property owner’s expense.
3.
Ordered Removals. The city manager may remove or cause or order to be removed any tree or part thereof, planted or growing in or upon any public street or alley which is in unsafe conditions, which by reason of its nature is injurious to sewers or other public improvements, or is affected with an injurious fungal disease, insect, or other pest.
D.
Arborist Certification. A tree contractor shall have on staff a certified arborist who is qualified to trim, treat, or remove street or city trees. The certified arborist must oversee all trimming work and certify that all work meets the city’s trimming specifications in subsection (B)(3) of this section. If a certified arborist is not on the staff of the tree contractor, the public works director, applying criteria developed by best practices as set forth by the ISA, must approve the tree contractor before the work begins. In cases where the professional opinion of a certified arborist differs from that of the public works director, the public works director may refer the matter to the sustainable and urban tree advisory board for a decision. Nothing in this section shall prevent the employees of public agencies with property in the city, who are not certified arborists, from trimming trees on the property of those public agencies.
(Ord. 25-09 § 7, 2025)
§ 3.6.210 Enforcement.
A.
Purpose. This section establishes an enforcement system to prohibit illegal tree activity to further the city’s goals for optimizing and enhancing the urban forest.
B.
Applicability – Where These Regulations Apply.
1.
City of Silverton. This section applies to all trees within the city of Silverton.
C.
City Authority. The city has the ultimate authority to:
1.
Interpret the provisions of this section and determine whether code criteria have been met.
2.
Establish conditions of permit and land use approval to ensure this section is properly implemented.
D.
Penalties. The following penalties apply to violations of the provisions of this section:
1.
A person who removes a tree regulated by this section without first obtaining the necessary permit from the city, removes a tree in violation of an approved permit, or violates a condition of an approved permit must pay a fine in an amount established in the fee schedule.
2.
Topping, pruning, or otherwise inflicting willful and negligent damage to a tree crown or roots in a manner that is inconsistent with ISA best management practices:
a.
Up to the amount established in the fee schedule or up to the appraised loss in value of the illegally topped or pruned tree as determined by an ISA certified arborist plus the arborist’s reasonable appraisal fee.
b.
Restoration of the tree crown, trunk, or root system as prescribed by an ISA certified arborist and approved by the city.
3.
Tree protection zone violations:
a.
Up to the amount established in the fee schedule.
b.
Restoration of the tree protection zone as prescribed by an ISA certified arborist and approved by the city.
4.
Evidence of Violation.
a.
If a tree is removed without the necessary permit, a violation will be determined by measuring the stump. A stump that is eight caliper inches or more in diameter will be considered prima facie evidence of a violation of this chapter.
b.
Removal of the stump of a tree removed without the necessary permit is a violation of this chapter.
c.
Proof of violation of this chapter will be deemed prima facie evidence that such violation is that of the owner of the property upon which the violation was committed.
(Ord. 25-09 § 7, 2025)
