Jefferson County Unincorporated
City Zoning Code
City Zoning Code
ARTICLE VII
Development Design Standards
Section 400.2160 Design Standards - Purpose.
[Zoning Order §7.010, 4-2-2008]
A.
This Article describes the specific design requirements to guide development in the County. The purpose of this Article is to:
1.
Protect property values, enhance community appearance, promote healthy living and preserve neighborhoods and rural character;
2.
Establish design parameters that will facilitate implementation of the development patterns of the Official Master Plan;
3.
Create design solutions that give developers flexibility to mix uses most effectively and innovatively develop and promote the public health, safety and welfare;
4.
Enable developers to create attractive, efficient and pedestrian-friendly/walkable living, shopping and working environments while preserving natural and environmental resources; and
5.
Increase public infrastructure efficiency and reduce or mitigate congestion through the implementation of the development patterns identified in the Official Master Plan and by the application of mixed uses and efficient densities.
Section 400.2170 Applicability.
[Zoning Order §7.020, 4-2-2008]
A.
The design standards in this Article are adopted to assist in ensuring that growth in the County occurs, as much as is possible, in accordance with the preferred growth alternative and with one (1) of the development patterns specified in the Master Plan. Development proposed in any location within the County shall conform to one (1) of the specified development patterns through the application of design standards appropriate to the applicable development pattern. This Article specifies design standards appropriate to zoning district classifications allowed in each of the development patterns. All development patterns may contain residential, commercial or industrial uses and zoning districts. The application of design standards to proposed development patterns shall be as follows:
Official Master Plan Development Pattern | Design Standards | |
|---|---|---|
Rural | None. See Section 400.2200 | |
Rural cluster | None. See Section 400.2200 | |
Large lot | Suburban | |
Suburban | Suburban | |
Mixed use | Mixed use | |
Mixed use addition | Mixed use | |
Infill | Mixed use, suburban or industrial — dependent on infill site | |
Industrial | Industrial |
The design standards supplement and enhance the use, density and district standards associated with the individual zoning districts and are provided as a tool to be used by developers and property owners intending to improve or modify their property. These standards reflect required, permitted and recommended standards of site design. Failure to meet any required standards indicated by "shall" or "must" or failure to attain any other applicable variance from a required standard could result in denial of a development plan. Permitted and recommended standards, indicated by "may" and "should", are intended to guide site design to a desired end result, rather than prescribe site design. |
B.
The design standards are interpreted and enforced in association with:
1.
The Official Master Plan;
2.
The purposes and objectives stated in each Article;
3.
Article V, which contains purposes, land use and lot dimension regulations for each zoning district;
4.
Article IV, including modifications allowed upon approval of a development plan as provided in Section 400.1390 (Article V) and Section 400.1230(E) (Article IV);
6.
All other standards of the Unified Development Order; and
7.
The standards of any other County code or ordinance.
Section 400.2200 Rural and Rural Cluster Design Standards - Implementation.
[Zoning Order §7.030, 4-2-2008]
Rural and rural cluster development patterns in the Official Master Plan shall be implemented by the standards of the "RA-5" District. Article V of this UDO contains performance and design standards for that district.
Section 400.2230 Suburban Design Standards - Implementation.
[Zoning Order §7.040, 4-2-2008]
Large lot and suburban development patterns in the Official Master Plan shall be implemented by the following design standards. They shall apply to the following zoning districts: "LR-2", "R-40", "R-20", "R-10", "R-7", "PR-1", "PR-2", "NC-1", "CC-2", "PC", "PB" and "NPI".
Section 400.2240 Suburban Design Standards - Objectives.
[Zoning Order §7.050, 4-2-2008]
A.
Residential Uses.
1.
Encourage the preservation or adaptive use of open space.
2.
Encourage maintenance of natural topography, substantial trees and tree groupings, hedgerows and other existing landscape features.
3.
Encourage developments with mixtures of densities, lot sizes, housing types and land uses.
4.
Encourage linking neighborhoods with safe, attractive pedestrian connections both along the street and on open space greenways.
5.
Connect residences to each other and to neighborhood parks, schools, public facilities and shops with direct pedestrian pathways.
6.
Encourage interconnectivity among neighborhoods to distribute traffic evenly and avoid excessive traffic on any one (1) street and limit traffic cutting-through from one neighborhood to another or from one County-maintained road to another.
7.
Minimize cut-through traffic within a neighborhood by providing a safe access configuration for internal and external traffic movement and design streets with appropriate speeds based upon the intended use, allowing for narrower widths and other traffic calming measures.
8.
Encourage parks and community facilities.
9.
Provide for varying front yard depths including allowance for increasing the proportion of rear yard area to front yard area to provide for privacy and to foster a more intimate and friendly neighborhood street.
B.
Non-Residential Uses.
1.
Facilitate efficient and attractive working conditions and provide places for employees to socialize and enjoy recreation. For example, development in the "PB" Planned Business Park District can be designed to facilitate socialization for business and pleasure by including restaurants, health clubs and other supportive uses that serve both the employees in the district and the community as a whole.
2.
Improve business efficiency and competitiveness as well as personal well-being among employees by locating business and personal services within the "PB" District and provide for a high degree of walkability between office buildings and these services.
3.
Facilitate pedestrian circulation among shops by encouraging appropriate storefront windows, signs and lighting in building design. Encourage the positioning of small local stores in front of big box stores to create a continuous shopping environment.
4.
Encourage the design of commercial developments as a "district" rather than a "strip", so that the groupings of businesses can be approached from more places around the perimeter resulting in less congestion and more accessibility, including pedestrians and bicyclists.
Section 400.2250 Suburban Design Standards - Residential Design Standards.
[Zoning Order §7.060, 4-2-2008]
A.
Residential uses implementing the suburban and large lot development patterns in the Official Master Plan (development proposals averaging two (2) acre lot sizes or less) shall meet the following design standards.
1.
Street design.
a.
Streets shall be laid out so that any single block face does not exceed one thousand five hundred (1,500) feet in length. Street layouts that provide right-of-way connections to the edge of the development adjacent to parcels of land that may develop in the future may be required where physically feasible considering grade and location so that this street pattern can be maintained, cut-through conflicts can be reduced and traffic circulation can be increased.
b.
Cul-de-sacs should be used where topographical conditions or natural features limit potential street connections. Alternative street layouts, such as eyebrows or loop lanes, may be used as an alternative to cul-de-sacs.
c.
If sidewalks are proposed on one (1) or both sides of a street, sidewalks should be separated from the street pavement by a planting strip with a minimum width of:
Section 400.2260 Suburban Design Standards - Non-Residential Design Standards.
[Zoning Order §7.070, 4-2-2008; Ord. No. 25-0117, 2-4-2025]
A.
Non-residential uses implementing the suburban and large lot development patterns in the Official Master Plan, not including industrial uses designed in accordance with Division 6 of this Article, shall meet the following design standards.
1.
Street design.
a.
Streets shall be laid out so that any single block face does not exceed one thousand five hundred (1,500) feet.
b.
Block faces may exceed one thousand five hundred (1,500) feet where internal drive aisles are provided to accommodate anticipated traffic. Internal drive aisles shall mimic the landscaping, planting strip, vehicle lane and curb cut design standards of the intersecting street.
c.
Sidewalks adjoining the front of a building facade shall be a minimum of eight (8) feet wide. Sidewalks separated three (3) or more feet from building facades may be as narrow as five (5) feet wide. Sidewalks should be provided along street rights-of-way.
d.
Street layouts should provide right-of-way connections to the edge of the development to adjacent sites, so that street patterns can be extended to future development, where topography allows and future anticipated land uses would benefit.
2.
Building relationship to street.
a.
Building entrances and entrances to business services are encouraged to face onto an existing street or major internal drive.
b.
Buildings are strongly encouraged to present their building fronts with windows and provide employee and general public entrances on an existing street or major internal drive.
c.
The open space requirement may be waived if an equally acceptable open space is provided on an adjacent lot subject to appropriate deeds, restrictions or easements or an equally acceptable open space, as identified in Division 8 of this Article, is dedicated to the public subject to County approval.
3.
Lot access, circulation and parking.
a.
To minimize curb cuts, vehicle and pedestrian connections between adjacent lots should be used to eliminate the need for multiple curb cuts along a street. Accesses through local alleys or major local access or local access streets are encouraged.
b.
An internal circulation system shall provide designated pedestrian connections between all buildings on the site and between the primary entrance of all buildings and the right-of-way. Pedestrian connections should be at least as frequent and direct as any vehicle access lanes.
c.
Parking areas with more than one hundred (100) spaces shall include designated walkways, at least five (5) feet wide, connecting the parking area with the building. One (1) designated walkway shall be installed for every two hundred fifty (250) feet of building frontage on the primary parking area. Locations where the designated walkways intersect with vehicle travel lanes should be minimized. These locations should have a paved surface differing from the vehicle travel lane, such as pavers or textured and colored pavement.
4.
Relationship to adjacent property.
a.
In instances where lots are smaller than six thousand (6,000) square feet or where buildings are less than fifty (50) feet from the right-of-way, the pedestrian and vehicular connections provided by the streets will be considered sufficient connections. In all other cases, alternatives, such as cross access easements or pedestrian alleys, should be considered.
b.
In instances where uses of different intensity or different zoning districts abut, a buffer meeting the requirements of Article XIV should be provided. However, transitions should be designed to ensure that the uses are compatible and may include:
(1)
A perimeter masonry wall, landscaping or a combination of a masonry wall and landscaping between three (3) to four (4) feet high and including gates for pedestrian access in appropriate places;
(2)
Access roads, overflow parking, storm drainage facilities or any other low intensity element of the site located near transition areas including landscaping elements, berms or screening walls that make the transitions to the less intense use; and
(3)
Four-sided architecture (designing all sides of the building with similar architectural details, materials and colors to avoid the appearance of a back side of any building), where rear of structure is visible from a public view.
Section 400.2290 Mixed Use Design Standards.
[Zoning Order Art. 7, Div. IV, 4-2-2008]
Both the mixed use and mixed use addition development patterns in the Official Master Plan shall be implemented by the following design standards. They shall apply to the following zoning districts: "PR-2" Planned Mixed Residential District and "PM" Planned Mixed Use District.
Section 400.2300 Mixed Use Design Standards - Objectives.
[Zoning Order §7.080, 4-2-2008]
A.
Residential Uses.
1.
Encourage developments with mixtures of densities, lot sizes and housing types.
2.
Foster neighborhood security with means for maintaining activity at all times of the day.
3.
Encourage linking neighborhoods with safe, attractive pedestrian connections both along the street and on open space greenways.
4.
Connect residences to each other and to neighborhood parks, schools, public facilities and shops with direct pedestrian pathways.
5.
Encourage interconnectivity among neighborhoods to distribute traffic evenly and avoid excessive traffic on any one street and limit traffic cutting-through from one neighborhood to another or from one County-maintained road to another.
6.
Minimize cut-through traffic within a neighborhood by providing a safe access configuration for internal and external traffic movement and design streets with appropriate speeds based upon the intended use, allowing for narrower widths and other traffic calming measures.
7.
Encourage parks and community facilities.
B.
Non-Residential Uses.
1.
Provide a focal point for neighborhoods surrounding office and commercial development.
2.
Allow a mixture of non-residential and residential uses to occur in a compact, pedestrian friendly manner.
3.
Allow vehicular access to the varied activities that occur in the mixed use development pattern, but never at the expense of pedestrian safety.
4.
Encourage buildings with diverse and interesting architectural styles that allow mixed use developments to attain a unique identity in the County.
5.
Prescribe compact development patterns that preserve rural qualities of outlying areas.
Section 400.2310 Mixed Use Design Standards - Residential Design Standards.
[Zoning Order §7.090, 4-2-2008]
A.
Residential uses implementing the mixed use and mixed use addition development patterns in the Official Master Plan shall meet the following design standards.
1.
Street design.
a.
Residential streets should be laid out so that any single block face does not exceed one thousand five hundred (1,500) feet in length. Streets may exceed these dimensions in the case of topographical constraints or natural features that are worthy of preservation. Mid-block pedestrian connections should be encouraged where they will provide safer, more efficient pedestrian access than conventional sidewalks along streets. These mid-block pedestrian crossings shall be installed with proper signage and/or signalization in order to alert vehicular traffic of the crossing. These dimensions shall provide a dedicated mid-block pedestrian connection through the block; each such block segment shall not exceed eight hundred (800) feet. Street layouts should provide right-of-way connections to the edge of the development to adjacent sites, so that street patterns can be extended to future development, where topography allows and future anticipated land uses would benefit.
b.
Paved sidewalks shall be provided in mixed use developments where connectivity to commercial uses from residential uses is necessary based upon an evaluation of:
2.
Lot access, circulation and parking.
a.
Vehicular access may be by a rear or side alley. Alley-facing garages shall be set back at least four (4) feet from the rear right-of-way or easement line. Where the property line extends to the centerline of the alley, the garage shall be set back ten (10) feet from the centerline.
b.
Exterior off-street surface parking may be located behind the principal structure.
c.
Driveways should be set back at least one (1) foot from the side lot line, except that shared driveways may be allowed through an easement designated on a plat.
3.
Relationship to adjacent property.
a.
The majority of residences are encouraged to be within one-half (½) mile of an existing or planned non-residential center of the mixed use development.
b.
Lower-density residential patterns should be located on edges that transition to rural areas or to other mixed use developments.
c.
Higher-density residential areas with eight (8) or more dwelling units per acre should be located within one thousand two hundred (1,200) feet of the non-residential center of the mixed use development, civic uses such as schools or common open space. Areas with less than eight (8) dwelling units per acre should be at least one thousand two hundred (1,200) feet from the non-residential center.
Section 400.2320 Mixed Use Design Standards - Residential and Non-Residential Design Standards.
[Zoning Order §7.100, 4-2-2008]
A.
Residential and non-residential uses implementing the mixed use and mixed use addition development patterns in the Official Master Plan shall meet the following design standards.
1.
Street design.
a.
Non-residential streets shall be laid out so that any single block face does not exceed six hundred (600) feet in length. Streets may exceed these dimensions in the case of topographical constraints or natural features that are worthy of preservation. These dimensions shall provide a dedicated mid-block pedestrian connection through the block.
b.
Cul-de-sacs or dead-end streets should not be used for non-residential streets. However streets that terminate with cross streets (t-intersections) are encouraged when used in conjunction with the location of significant buildings or architectural elements at the termination of the street.
c.
Sidewalks shall be required and should be located near the street edge. Tree wells or landscape wells are encouraged along the street edge every seventy-five (75) feet on center. Location of sidewalks should reflect tree locations.
d.
On-street parking is encouraged to provide a buffer for pedestrians, calm traffic and reduce vehicle speeds and to reduce the need for dedicated off-street parking lots.
e.
Street layouts should provide right-of-way connections to the edge of the development to adjacent sites, so that street patterns can be extended to future development, where topography allows and future anticipated land uses would benefit.
2.
Lot access, circulation and parking.
a.
Sidewalks adjoining the front of a building facade shall be a minimum of eight (8) feet wide. Sidewalks separated three (3) or more feet from building facades may be as narrow as five (5) feet wide. Sidewalks should be provided along street rights-of-way.
b.
Vehicle access is encouraged through rear alleys. In cases where rear alleys are not feasible, vehicle access points should be limited to side streets.
c.
Any off-street parking shall be behind the building or located to the side of the building. Any parking located to the side of the building shall be set back at least ten (10) feet from the right-of-way and screened. A fence or wall screening of a minimum of three (3) feet high shall be constructed between the parking lot and the sidewalk. Landscaping approximately three (3) feet high shall be provided along with the fence or wall screening. The design and character of the combined landscaping and fence, masonry wall or decorative wall screening should be compatible with the architectural design and character of adjacent buildings.
d.
No more than thirty-five percent (35%) of any single block should be dedicated to off-street parking. However, blocks that are set up for centralized public parking to serve multiple non-residential uses in the mixed use center may occupy up to fifty percent (50%) of a block. Combined landscaping and fence, masonry wall or decorative wall screening should be provided for each street frontage of a parking area. Such screening should be compatible with the architectural design and character of surrounding buildings on the fronting street. The screening should be a minimum of three (3) feet high.
3.
Relationship to adjacent property. Connections shall be maintained between residential and non-residential uses. Transitional areas between residential and non-residential uses should be designed to ensure that the uses are compatible and may include:
a.
A perimeter masonry wall, landscaping or a combination of a masonry wall and landscaping, though any wall should be between three (3) to four (4) feet high and include gates for pedestrian access in appropriate places;
b.
Vehicle or pedestrian alleys, access roads, overflow parking, storm drainage facilities or any other low intensity element of the site near transition areas, though any such element should be accompanied by landscaping elements, berms or screening walls that make the transitions to the less intense use appropriate;
c.
Four-sided architecture (designing all sides of the building with similar architectural details, materials and colors to avoid the appearance of a back side of any building) where rear of structure is visible from a public view; and
Section 400.2350 Infill Development Design Standards - Implementation.
[Zoning Order §7.110, 4-2-2008]
All infill development shall conform to one (1) of the design standards (Divisions 2 through 6) set forth in this Article. The location of the proposed infill development and adjacent uses shall be the primary considerations in determining which design standard shall apply to the proposed development.
Section 400.2380 Industrial Design Standards.
[Zoning Order Art. 7, Div. VI, 4-2-2008]
The industrial development pattern in the Official Master Plan shall be implemented by the following design standards. They shall apply to the "PI" Planned Industrial District. These standards shall not apply to industrial uses that are integrated into the development built in the suburban or mixed use development patterns and those industrial developments shall be subject to the design standards applicable to those particular patterns.
Section 400.2390 Industrial Design Standards - Objectives.
[Zoning Order §7.120, 4-2-2008]
A.
Development in the industrial districts:
1.
Encourage the kinds of amenities and services for employees that the Planned Business Park districts provide (distances to common facilities may be greater due to the horizontal expansiveness of most industrial uses, warranting close attention to the location of common facilities in site planning to minimize these distances);
2.
Utilize building materials, orientation and landscaping that are visually attractive thereby affecting the value and reputation of the County as a whole; and
3.
Minimize the impact of operations on the surrounding community.
Section 400.2400 Industrial Design Standards - Standards.
[Zoning Order §7.130, 4-2-2008]
A.
Building Design.
1.
Industrial buildings should be designed with four-sided architecture as in Section 400.2320(3)(c) above.
2.
Mechanical units shall be screened as set forth in Section 400.2400(F)(2) below. Awnings, canopies and arcades are permitted to extend into the front yard setback to provide shelter for pedestrians from wind, rain and snow.
3.
Solar energy devices, if provided, shall be integral to overall building design.
B.
Street Design.
1.
Streets should be laid out so that any single block face does not exceed one thousand five hundred (1,500) feet. Street layouts should provide right-of-way connections to the edge of the development to adjacent sites, so that street patterns can be extended to future development, where topography allows and future anticipated land uses would benefit.
2.
In instances where block faces exceed one thousand five hundred (1,500) feet, internal drive aisles should be provided to create at least as frequent access as would have been provided by the street patterns in Section 400.2400(B)(1) above. Internal drive aisles shall mimic the design standards of streets, including landscaping, sidewalks, planting strips, vehicle lanes and curb cuts.
3.
Curb cuts and internal drive aisles shall be separated by a minimum of two hundred (200) feet from one another or intersecting street rights-of-way.
4.
Alternative pedestrian connections shall be provided both to the site and between all buildings within a development.
5.
Sidewalks are optional, but if sidewalks are provided, sidewalks should be separated from the street pavement by a planting strip with a minimum width of:
6.
In instances where on-street parking has been approved by the County, sidewalks may abut the street provided the minimum sidewalk shall be at least eight (8) feet wide.
C.
Building Relationship To Street.
1.
Building entrances and entrances to business services are encouraged to face onto an existing street or a landscaped open space.
2.
Industrial buildings are strongly encouraged to present their building fronts with windows and provide employee and general public entrances on an existing street or major internal drive.
D.
Site Coverage.
1.
Maximum FAR (see Table 5-2 of Article V). The FAR shall be applied only to the area proposed for initial development, not to area left undeveloped and reserved for future expansion.
2.
Impervious area coverage may extend up to eighty percent (80%) of the development site. Porous surfaces that allow storm water to infiltrate below the surface, such as porous concrete or asphaltic materials, are encouraged.
E.
Access, Circulation And Parking. If a development abuts or contains an existing or proposed limited access highway or arterial street, the Planning and Zoning Commission and/or County Council may require frontage roads or parallel streets to separate through and local traffic and to provide for visually safe and attractive roadways:
1.
A minimum setback of twenty (20) feet from street rights-of-way and adjoining residential property shall be required for all surface parking lots.
2.
A minimum setback of twenty (20) feet from street rights-of-way shall be required for all circular drive drop-offs.
F.
Relationships To Adjoining Property.
1.
Setbacks. Buildings shall be set back a minimum of fifty (50) feet from any residentially zoned property.
2.
Buffer screen standards.
a.
In addition to or in lieu of, the requirements described in Article XIV, Table 14-1, developments adjoining existing residential or residentially zoned property shall provide screening in the rear and side yards consisting of a minimum of: a buffer of at least fifty (50) feet of existing mature woodlands provided that they are contained on the same lot or tract of land as the proposed development; or at least two (2) staggered rows of three (3) foot high evergreen trees placed six (6) feet on center; or a constructed earthen berm at least ten (10) feet in width and six (6) feet in height and with a slope not exceeding a 3:1 ratio; or a sight-proof fence at least six (6) feet in height constructed of either weather-resistant wood (excluding plywood), masonry wall (with masonry/brick pilasters), rock, brick or vinyl (weather-resistant composite material). The required materials are to provide for ease of maintenance and longevity of the required buffer screen.
b.
A live planted screen alternative or combination screen consisting of berms and live plants may also be substituted for the above or combination thereof if the Planning and Zoning Commission approves this alternative, after a finding that the alternative buffer screen provides a more pleasing environment for the adjoining properties.
Section 400.2430 Geotechnical Study Requirements.
[Zoning Order §7.135, 4-2-2008]
A.
The geotechnical study is to recommend courses of action that will allow for the safe development of a site that may contain geological or soil constraints. When required to provide a geotechnical study, the minimum information shall be provided in the study:
1.
A description of the site and the existing topographic, geologic and soils information to include slope categories, geologic formations, soil types and vegetative cover.
2.
A statement and description of field test data. This information must be adequate to accurately map all shale formations, colluvial soils or loess deposits on natural slopes in excess of twenty percent (20%), describe any shale beds, soil layer thickness, the dip of any shale beds, the slope of any residual clay layers having relatively thick soil layers above and the presence of any subsurface water where grading is proposed to occur.
3.
Description of laboratory test data. This should relate to the information found in the above described data gathering requirements. The internal strength properties of all shale or other potentially weak materials or contacts should be measured.
4.
An analysis of the above gathered information relative to any potential site development problems. Landslide analysis should be broken into properties such as affects of slope, material properties, dip of bedding planes, slope on inclined loess or colluvium/residual clay layers, effects of hydrostatic pressure, other effects of subsurface water, etc.
5.
Recommendations to address any problems such as landsliding or expansive soils.
6.
Recommendations for the proper placement or compaction of fill to avoid potential problems or for suitable foundations.
7.
Recommendations for testing during construction such as density testing including the location and frequency of such testing.
8.
Recommendations for walls, plant cover or other slope treatment that may be necessary to ensure slope stability.
B.
All projects requiring a geotechnical study shall also submit a post construction report that includes as a minimum the following information:
Section 400.2440 Trash Enclosures.
[Zoning Order §7.140, 4-2-2008]
Where required, all exterior non-residential trash storage containers shall be screened so that they are not visible from off the property. Where individual trash enclosures are provided, screening shall be constructed of masonry walls, decorative walls or fence, with a gate (not plastic or vinyl) painted to be compatible with the color of the walls or fence and the building it is to serve.
Section 400.2450 Vertical Wall/Cut and Usable Space Requirements.
[Zoning Order §7.145, 4-2-2008]
A.
Any development where a retaining wall or vertical cut is proposed in an upward-sloping yard shall provide a minimum fifteen (15) foot wide fall zone easement from the bottom of the wall. Any structure requiring the issuance of a Jefferson County building permit, except a deck without walls or a roof, shall not be located within the fall zone easement.
B.
A portion of every rear yard in residential developments shall provide adequate usable space for outdoor recreation by the occupants of the lot. At least thirty percent (30%) of the required rear yard area must be usable, unless a variance is granted by the Jefferson County Board of Zoning Adjustment. A usable space is a contiguous area with grade less than thirty percent (30%).
Section 400.2460 Lighting Standards.
[Zoning Order §7.150, 4-2-2008; Ord. No. 11-12-2008A §§1 — 2(7.150), 11-12-2008; Resolution 1-14-2010A Exh. A, 1-14-2010; Ord. No. 10-0145 §§1 — 2, 2-18-2010]
A.
Commercial developments and other developments proposing parking lot and security lighting shall:
1.
Provide a photometric diagram indicating the levels of foot-candles throughout the site and at the property lines and as a part of the preliminary development plan.
2.
Utilize lighting so as to direct the light downward to avoid "light seepage". The light filament shall be shielded so the filament will not be seen from neighboring properties. All lighting serving parking lots shall be cut-off fixtures as defined by the Illuminating Engineering Society of North America.
3.
Provide lighting at the intersection of each drive aisle or driveway with the private, County-maintained and State-maintained streets.
4.
Provide lighting in accordance with the following table:
Table 7-1. Lighting Requirements | ||||
|---|---|---|---|---|
Basic1 | Enhanced Security2 | |||
Minimum foot-candles on pavement3 | 0.2 fc | 0.5 fc | ||
Maximum foot-candles on pavement | 4.0 fc | 7.5 fc | ||
Uniformity ratio, maximum:minimum4 | 20:1 | 15:1 | ||
Minimum foot-candles at 5 feet above pavement5 | 0.1 fc | 0.25 fc | ||
fc = foot-candles | ||||
1 | For typical conditions. During periods of non-use, the illuminance of certain parking facilities should be turned off or reduced to conserve energy. If reduced lighting is to be used only for the purpose of property security, it is desirable that the minimum (low point) value not be less than one-tenth (0.1) foot-candle. Reductions should not be applied to facilities subject to intermittent night use, such as at apartments, hospitals and transportation terminals. | |||
2 | The enhanced security lighting level should be used when personal security is an issue, such as where the parking facility is used during all hours of the day and night, where special security needs exist or where vandalism or crime are possible. | |||
3 | Measured on the parking surface, without any shadowing effect from parked vehicles or trees at points of measurement. | |||
4 | The highest horizontal illuminance point at grade, divided by the lowest horizontal illuminance point or area should not be greater than the values shown. | |||
5 | Measured at five (5.0) feet above the parking surface at the point of the lowest horizontal illuminance, excluding facing outward along boundaries. | |||
5.
Where security lighting is proposed, the following table shall govern the range of permissible light levels for the listed applications. Where a proposed security lighting application is not shown, the table shall be used as a guide for establishing the range of permissible light levels.
Table 7-2. Security Lighting Application | |||
|---|---|---|---|
Location | Average Horizontal Illumination Level on Ground | ||
Large open areas | 0.5 — 2.0 fc 1 | ||
Buildings | 0.5 — 2.0 fc 1 | ||
Perimeter fence | 0.5 fc | ||
Entrances | 3 fc | ||
Pedestrian pathways and access routes | 4 — 6 fc | ||
fc = foot-candle | |||
|---|---|---|---|
1 | The greater the brightness of the surrounding area, the higher the illuminance required to balance the brightness. | ||
C.
Floodlight fixtures are prohibited on parking lot light poles, but may be used as accent lighting only.
D.
Wall pack light fixtures are allowed, provided that full cutoffs are utilized to direct the light downward; and provided that no light source is visible. Wall pack fixtures located internally to a common area for multiple buildings may use light spreading fixtures approved by the Director, provided they cannot be seen from residential property or from adjacent streets.
Section 400.2470 Open Space.
[Zoning Order §7.155, 4-2-2008]
A.
Residential Developments.
1.
In developments with common open space, the design shall provide at least one (1) access point from a street within the development to such common ground and multiple points of access are encouraged.
2.
Common open space is encouraged to incorporate natural features and recreational designs. Common open space may include a park, playground, greenway or natural preserve meeting the following standards:
a.
Each such park should be at least one (1) acre and contain at least one (1) acre for every fifty (50) dwelling units it is designed to serve.
b.
Playgrounds should include at least one-quarter (¼) acre unless located in a park. Each playground shall contain at least ten thousand (10,000) square feet for every fifty (50) dwelling units it is designed to serve.
c.
Greenways should provide connections to destinations of the neighborhood and may follow along streams or floodplains. Greenways shall be at least twenty (20) feet wide at all locations. Greenways should include trails or paved pedestrian/bike paths.
Greenways should be designed to address issues of safety, visibility and access for its users. A well-designed greenway will be designed so that both the users and the trail are visible; so that ingress and egress is controlled by some means such as a fence or hedge signaling to users where they are and are not to walk; so that the private and public spaces are distinguishable; and so that the greenway/trail can be maintained by the homeowners' association.
B.
Non-Residential Developments.
1.
For non-residential sites in excess of two (2) acres, at least ten percent (10%) of each lot should be open space.
2.
Open space should consist of landscaped areas, landscape islands, natural preserves or plazas or courtyards meeting the following requirements:
a.
Landscaped areas include buffers, yards or any pervious surface meeting the landscaping requirements of Article XIV. Retention or detention basins may be used to meet open space requirements, if it is designed as a visual amenity for the development and the area surrounding the basin is accessible by walking paths or other recreation facility.
c.
Plazas or courtyards shall be at least four hundred (400) square feet and be designed with landscaping materials and public seating. However, only fifty percent (50%) of a lots required open space shall consist of plazas or courtyards.
C.
Mixed Use Developments — Residential Uses.
1.
In developments with common open space, the design shall provide at least one (1) access point from a street within the development to such common ground and multiple points of access are encouraged.
2.
Common open space is encouraged to incorporate natural features and recreational designs. Common open space may include a park, playground, greenway or natural preserve meeting the following standards:
a.
Each such park should be at least one (1) acre and contain at least one (1) acre for every fifty (50) dwelling units it is designed to serve.
b.
Playgrounds should include at least one-quarter (¼) acre unless located in a park. Each playground shall contain at least ten thousand (10,000) square feet for every fifty (50) dwelling units it is designed to serve.
c.
Greenways should provide connections to destinations of the neighborhood and may follow along streams or floodplains. Greenways shall be at least twenty (20) feet wide at all locations. Greenways should include trails or paved pedestrian/bike paths.
d.
Greenways should be designed to address issues of safety, visibility and access for its users. A well designed greenway will be designed so that both the users and the trail are visible; so that ingress and egress is controlled by some means such as a fence or hedge signaling to users where they are and are not to walk; so that the private and public spaces are distinguishable; and so that the greenway/trail can be maintained by the homeowners' association.
D.
Mixed Use Developments — Residential And Non-Residential Uses. Each block should contain or be within one thousand (1,000) feet from one (1) of the following types of common open space:
1.
A courtyard or plaza with landscaping materials and public seating;
2.
A greenspace or small park bordering a street right-of-way on at least two (2) sides designed with landscaping materials and public seating; or
3.
A greenway connecting the non-residential center of the mixed use development to surrounding neighborhoods.
Section 400.2500 Access Management Guidelines - Purpose.
[Zoning Order §7.160, 4-2-2008]
Access management entails providing (or managing) access to land development while simultaneously preserving the flow (safety, capacity and speed) of traffic on the surrounding road system. Benefits that arise from the implementation of access management guidelines include less interruptions and congestion in traffic flow, improved roadway safety and maintaining roadway capacity.
Section 400.2510 Functional Classification System - General.
[Zoning Order §7.170, 4-2-2008]
A.
Functional classification is the process by which all roadways and streets are grouped into classes according to the type of service that they are intended to provide. There are three (3) basic highway functional classifications: arterial, collector and local roads and streets. All roads and streets are grouped into one (1) of these classes, depending on the character of the traffic and the degree of land access that they allow.
B.
Roadways that are a part of the public road system are functionally classified as an integral system regardless of jurisdictional control of those roads/streets. The classification process does not consider administrative or jurisdictional systems (state, County or City). Roads are separated into different functional classification systems by their geographic location in rural, small urban or urbanized areas.
C.
Functional classification defines the nature that any particular street should play in serving the mobility and access functions within a transportation network. Urban and rural areas have fundamentally different characteristics, such as density and types of land use, density of highway and street networks, nature of travel patterns and the way in which all these elements are related. In some rural circumstances with sparse roadway networks, many of the County-maintained roads may serve a dual role, providing primary local access and regional mobility.
Section 400.2520 Streets - Jefferson County Functional Classes.
[Zoning Order §7.180, 4-2-2008]
A.
Following is the functional classification system for the roadway system in unincorporated Jefferson County based on the regional network as defined by East West Gateway Council of Governments. The Public Works Department maintains an index of the individual roads/streets or segments and their functional classifications.
1.
Principal arterial. Principal arterials are stratified into three (3) distinct classifications: interstates, freeways and other principal arterials with limited access control. Principal arterials shall not consist of local subdivision streets and shall be public Federal, State or County-maintained facilities. A principal arterial facilitates substantial County-wide and inter-County travel; in addition, virtually all urbanized areas and other significant population centers are served by principal arterials.
2.
Minor arterial. The minor arterial system provides linkage between cities and towns and is a critical component of an integrated, County-wide roadway network. A minor arterial serves an urban area if it penetrates or comes within one (1) mile of the urban area boundary (adapted from Federal Highway Administration. Highway Functional Classification: Concepts, Criteria and Procedures, Section II, July, 1974).
3.
Collector. A collector serves urban areas and other traffic generators of importance that are not served by higher systems and are generally maintained and operated by the Federal or State government. These roadways function to connect these areas of significant traffic generation with nearby towns or with routes of higher classification.
4.
Local County. Local County-maintained roads connect locally important traffic generators with the less developed parts of the County. These facilities collect traffic from other local roads and streets. Local County roads shall not be located within residential subdivisions for reasons of public safety.
5.
Major local access. Major local access streets are subdivision streets constructed and maintained by the subdivision or other development. These streets act as mini-collectors within subdivisions. Thus, direct access from individual lots to the streets should be minimized and parking within the through travel lanes should be restricted where feasible.
6.
Local access. The local access street system is comprised of all other facilities not included on one (1) of the higher systems. Local access streets are subdivision streets constructed and maintained by the subdivision or other development. Within the context of the rural functional classification system, local streets enable travel over short distances and provide direct access to adjacent land.
7.
Local access alley. The local access alleys are dedicated public rights-of-way or private easement that afford a secondary means of access to abutting property and are not intended for general traffic circulation. Local access alleys are constructed and maintained by the subdivision or other development.
Section 400.2530 Street Standards - General.
[Zoning Order §7.190, 4-2-2008; Ord. No. 20-0406, 9-29-2020; Ord. No. 25-0117, 2-4-2025]
A.
This code is intended to address typical design guidelines and minimum requirements for the major local access streets, local access streets and local access alleys constructed and maintained by the subdivision or other development. This code does not pertain to County roads and other highways maintained by various public agencies.
B.
Horizontal alignment of streets at an intersection should be as near as possible a right angle as topography and other geographic features allow.
C.
If, after review by the Planning Division, it is determined that there is no alternate location that does not conflict with the offset required by this UDO or Chapter 515 of the Code of Ordinances of Jefferson County, and that adequate sight distance may be achieved, the Director may approve an entrance, street, or driveway location without the need for a deviation or modification. The Director shall notify the Planning and Zoning Commission of approvals granted pursuant to this Section.
Section 400.2540 Trip Generation Estimate Procedure.
[Zoning Order §7.195, 4-2-2008; Ord. No. 07-30-2008A §§1 — 2(7.195), 7-30-2008]
In order to approximate the daily number of trips generated by a solely residential development, trip generation rates from the ITE Trip Generation Manual based on number of dwelling units should be used. The table below shows the approximate daily traffic volumes based on the number of residential units that the street serves.
Table 7-3. Trip Generation Estimates | ||
|---|---|---|
Daily Traffic Volume | Dwelling Units Served | |
Less than 400 | Under 50 dwelling units | |
400 — 1,519 | 50 — 189 dwelling units | |
1,520 — 1,999 | 190 — 249 dwelling units | |
2,000 — 2,500 | 250 — 315 dwelling units | |
Over 2,500 | Over 315 dwelling units | |
Trip generation for non-residential or mixed development shall be determined using the ITE Trip Generation Manual. The most current version of the ITE Trip Generation Manual shall be used. |
Section 400.2550 Street Standards - Minimum Right-Of-Way and Improved Surface Width.
[Zoning Order §7.200, 4-2-2008; Ord. No. 11-12-2008A §§1 — 2(7.200, Tbls. 7-4 — 7-5), 11-12-2008]
Table 7-4. Minimum Design Standards for Two-Way Streets | |||||||
|---|---|---|---|---|---|---|---|
Type of Street | Vehicles per Day | Drainage Type | Minimum Shoulder Width, if used | Total Improved Surface Width** | Minimum ROW*** | ||
No Parking | Parking — one side | ||||||
Major local access | >2,500 | a/b | 8' | 26' | 36' | 32' | |
Local access street | 2,000 — 2,500 | b | NA | 26' | 34' | 32' | |
1,520 — 1,999 | b | NA | 24' | 28' | 30' | ||
400 — 1,519 | a/b | 5' | 22' | 28' | 28' | ||
<400 | a/b | 2' | 20' | 28' | 26' | ||
Local access alley | <400 | a | 0' | 14' | 26' | 0'/20'**** | |
a | Open, streetside drainage swales or ditches are allowed for streets adjacent to residential lots one (1) acre in size or larger. | |||||
b | Curbs and gutters are required | |||||
** | All pavement measurements taken from back of curb to back of curb if present. Total improved surface width includes shoulders, where present. Where permitted, the shoulder areas can also accommodate all or part or the required parking lane width(s). If parking is added to the second (2nd) side, add seven (7) feet to the surface width. | |||||
*** | Minimum right-of-way shall be three (3) feet behind back of curb on both sides, required sidewalks and any open drainage may be located within right-of-way or easement. | |||||
**** | Right-of-way: Zero (0) feet for private access alleys, twenty (20) feet for dedicated public access alleys. | |||||
Figure 7-1 Major Local Access Street (> 2,500 vehicles per day) with curbs but no parking (not to scale) |
|---|
 |
Figure 7-2 Local Access Street (2,000 — 2,500 vehicles per day) with curbs and parking on one (1) side (not to scale) |
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 |
Figure 7-3 Local Access Street (400 — 1,519 vehicles per day) with curbs but no parking (not to scale) |
|---|
 |
Table 7-5. Minimum Design Standards for One-Way and Median Divided Streets | ||||||
|---|---|---|---|---|---|---|
Type of Street | Vehicles per Day | Drainage Type | Minimum Shoulder Width, if used (left/right) | Total Improved Survace Width** | Minimum ROW*** | |
No Parking | Parking — one side | |||||
Major local access | >2,500 | a/b | 4'/8' | 15' | 25' | 21' |
Local access street | 2,000—2,500 | b | NA | 13' | 24' | 19' |
1,520—1,999 | b | NA | 13' | 24' | 19' | |
400—1,519 | a/b | 2'/5' | 13' | 24' | 19' | |
<400 | a/b | 0'/2' | 13' | 24' | 19' | |
Local access alley | <400 | a | 0'/0' | 10' | 24' | 0''/20'**** |
a | Open, streetside drainage swales or ditches are allowed for streets adjacent to residential lots one (1) acre in size or larger. | |||||
b | Curbs and gutters are required | |||||
** | All pavement measurements taken from back of curb to back of curb if present. Total improved surface width includes shoulders, where present. Where permitted, the shoulder areas can also accommodate all or part or the required parking lane width(s). If parking is added to the second (2nd) side, add seven (7) feet to the surface width. | |||||
*** | Minimum right-of-way shall be three (3) feet behind back of curb on both sides, required sidewalks and any open drainage may be located within right-of-way or easement. | |||||
**** | Right-of-way: Zero (0) feet for private access alleys, twenty (20) feet for dedicated public access alleys. | |||||
Section 400.2560 Street Standards - Minimum Pavement Standards.
[Zoning Order §7.205, 4-2-2008; Ord. No. 07-30-2008A §§1 — 2(Tbl. 7-7), 7-30-2008; Resolution 1-14-2010A Exh. A, 1-14-2010; Ord. No. 10-0145 §§1 — 2, 2-18-2010; Ord. No. 16-0100 §2, 1-4-2016; Ord. No. 20-0406, 9-29-2020]
Every access shall be designed to carry a weight load of at least an HS20 design vehicle (AASHTO). Alternative methods of pavement design may be approved only by the Planning Commission with a recommendation from the Public Works Department and shall not be less than the structural equivalency of the street type in Table 7-6 by Traffic Volume Category. In the absence of a pavement construction standard in this UDO, the standards shall be in accordance with the St. Louis County Standard Specifications for Highway Construction and the Design Criteria for the preparation of Improvement Plans in effect as of the date of the adoption of this UDO as stated in Section 400.110. The following two (2) tables provide requirements for pavement thickness based on daily traffic volume.
Table 7-6. Pavement Thickness | |||||
|---|---|---|---|---|---|
Traffic Volume Category | Pavement Type | Concrete1 | Asphalt2 | Combination2, 3 | Alt. Option4 |
Heavy/Industrial (HI) | Concrete | 8 | |||
Asphalt surface | 2 | 2 | |||
Asphalt base | 7 | ||||
Concrete base | 7 | ||||
Rock base | 4 | 4 | 4 | ||
High Volume (HV) | Concrete | 7 | |||
Asphalt surface | 2 | 2 | |||
Asphalt base | 6 | ||||
Concrete base | 6 | ||||
Rock base | 4 | 4 | 4 | ||
Medium Volume (MV) | Concrete | 6 | |||
Asphalt surface | 2 | 2 | |||
Asphalt base | 5 | ||||
Concrete base | 5 | ||||
Rock base | 4 | 4 | 4 | ||
Low Volume (LV) | Concrete | 6 | |||
Asphalt surface | 2 | 2 | |||
Asphalt base | 4 | ||||
Concrete base | 5 | ||||
Rock base | 4 | 4 | 4 | ||
Very Low Volume (VLV) | Concrete | 6 | |||
Asphalt surface | 2 | 2 | 3 | ||
Asphalt base | 3 | ||||
Concrete base | 5 | ||||
Rock base | 4 | 4 | 4 | 8 | |
1 | All concrete streets shall be a six (6) sack mix with four thousand (4,000) p.s.i., twenty-eight (28) day strength. A three (3) inch slump is the maximum. Details shall be subject to approval by the County. |
2 | Thickness is of compacted asphalt. For asphalt streets, no layer shall have a compacted thickness of greater than four (4) inches. |
3 | For combination pavement, all concrete shall be a five and one-half (5½) sack mix with a four thousand (4,000) p.s.i., twenty-eight (28) day strength. A three (3) inch slump is the maximum. Details shall be subject to approval by the County. |
4 | Alternative Option may only be used in the "RA-5" and "LR-2" zone districts for developments less than fifty (50) lots and with each lot being four (4) or more acres in size. Any proposed alternative method shall not have less than three (3) inches of asphalt. |
Table 7-7. Daily Traffic Volume by Zone District | ||||
|---|---|---|---|---|
Zone District | Daily Traffic Volume | |||
<400 | 400 — 1,519 | 1,519 — 2,500 | >2,500 | |
"RA-5" | VLV | LV | MV | HV |
"LR-2" | VLV | LV | MV | HV |
"R-40" | VLV | LV | MV | HV |
"R-20" | VLV | LV | MV | HV |
"R-10" | VLV | LV | MV | HV |
"PR-1" | VLV | LV | MV | HV |
"PR-2" | VLV | LV | MV | HV |
"NC-1" | LV | MV | MV | HV |
"PC" | LV | MV | MV | HV |
"CC-2" | LV | MV | HV | HV |
"PB" | LV | MV | HV | HI |
"NPI" | MV | HV | HV | HV |
"PI" | HV | HV | HV | HI |
VLV | = | Very Low Volume |
LV | = | Low Volume |
MV | = | Medium Volume |
HV | = | High Volume |
HI | = | High Volume |
Streets in the "PM" District shall use the most applicable pavement type based upon use (residential, commercial, etc.) and daily traffic volume. |
Section 400.2570 Standards - Additional Design Standards.
[Zoning Order §7.210, 4-2-2008]
Table 7-8. Additional Design Standards for Streets | ||||||
|---|---|---|---|---|---|---|
Type of Street | Maximum percent grade of a street | Minimum horizontal radius of curve | Minimum length of vertical curve on a street in feet | Minimum length of tangent between horizontal reverse curves | ||
Minimum length | Feet for each algebraic difference in grade (K factor) | |||||
Major local access | 12% | 100 feet | 75 feet | but not less than | 30 feet | 100 feet |
Local access | 14% | 100 feet | 50 feet | but not less than | 20 feet | 0 feet |
Local alley access | 14% | 50 feet | 50 feet | but not less than | 10 feet | 0 feet |
Section 400.2580 Street Standards - Curb Radii.
[Zoning Order §7.205, 4-2-2008; Resolution 1-14-2010A Exh. A, 1-14-2010; Ord. No. 10-0145 §§1 — 2, 2-18-2010]
Where two (2) streets intersect, the curb at each intersection shall be rounded with a radius as indicated below.
Table 7-9. Intersection of Functionally Classified Streets | |||
|---|---|---|---|
Type of Street | Minimum Corner Radius | ||
Local Access Alley | to | Any Street | 5' |
Local Access or Major Local Access | to | Local Access or Major Local Access | 15' |
Local Access or Major Local Access | to | County Maintained Street | 30' |
NOTE: Measurement taken at back of curb. | |||
Section 400.2590 Traffic Calming and Alternative Intersection Treatments.
[Zoning Order §7.230, 4-2-2008]
Where utilized, traffic calming and/or alternative intersection treatments may be approved by the County. Said treatments shall be designed in accordance with a nationally recognized standard or recommended practice acceptable by the County.
Section 400.2600 Visual Clearance Standards - Minimum Sight Distance.
[Zoning Order §7.240, 4-2-2008; Ord. No. 11-12-2008A §§1 — 2(7.240), 11-12-2008; Resolution 1-14-2010A Exh. A, 1-14-2010; Ord. No. 10-0145 §§1 — 2, 2-18-2010; Ord. No. 25-0117, 2-4-2025]
A.
Proper lines of sight shall be maintained at all intersections and driveways. Traffic on streets classified as alley access, local access and major local access streets shall be required to stop or yield at intersections with other alley access, local access and major local access streets or higher classification streets and roads.
B.
The minimum sight clearance is determined by the distance that must be kept clear for visibility of approaching vehicles from the stopping point to the distance along the midpoint of the approaching travel lane, measured three (3) feet above the pavement surface. (These requirements are for level conditions; for grade adjustments a more detailed analysis of a particular situation may be necessary.) Determination of the minimum sight distance should generally follow MoDOT standards as follows:
1.
Both vertical and horizontal alignment can limit sight distance. In order to measure actual sight distance limited by horizontal or vertical alignment, place a sighting target four and one-fourth (4.25) feet above the edge of pavement at a point twelve (12) feet from the edge of pavement (approximate location of a driver approaching the street, three (3) feet right of the adjacent left lane line) at the proposed driveway location. Sighting from a height of three and one-half (3.5) feet, move along the cross street away from the proposed driveway location to a point beyond where the target disappears. Now move toward the target until it can first be seen and place a mark on the main street pavement. Measure the distance along the cross street between the mark and the target. Measurement may be made with an accurate measuring device mounted on an automobile. This measured distance is the intersection sight distance (per the MoDOT Permitting Manual, pages 17 — 19).
Figure 7-4 Intersection Clear Sight Distance | |
|---|---|
 | |
In the case of vertical sight distance, a minimum one (1) foot clearance between the direct line of sight and the crest of the roadway is required. If the determination is impractical to measure in the field, it must be demonstrated on a design plan sheet illustrating a cross section view of sight distance as described above. |
2.
Stopping sight distance shall be determined by Chapter 515 of the Code of Ordinances of Jefferson County.
a.
No building or other type of visual obstruction shall be placed, erected or maintained within the sight triangle. Street trees, certain types of vegetation, poles and posts are allowed within the sight triangle, provided that they do not have any foliage, limbs or other obstructions between three (3) and ten (10) feet above ground level, are not more than fifteen (15) inches in diameter and are not closer than thirty-five (35) feet to the intersecting pavement edge. Certain types of decorative fences are also allowed within the sight triangle provided that their design allows a clear view to be maintained throughout the clearance area and are not placed closer than thirty-five (35) feet to the intersecting pavement edge lines at intersection corners. These requirements are applicable to intersections with rounded corners.
b.
At roundabout intersections, the clear vision area shall include all points twenty-five (25) feet distant from the pavement edge lines of the outside curves.
c.
Within the triangular area formed by lines thirty-five (35) feet in length along the pavement edges of intersecting streets or a driveway intersecting the right-of-way of a street, from their point of intersection, no landscaping or screening materials, signs, parked vehicles or other objects, other than essential directional signs, traffic control devices and utility structures approved by the County, shall interfere with the line of sight between a height of three (3) feet and ten (10) feet above the adjoining street or driveway pavement.
Figure 7-5 Intersection Corner Sight Clearance Triangle | |
|---|---|
 |
C.
Nothing in this Section shall be construed to allow placement of objects in the street right-of-way.
Section 400.2610 Driveway Requirements - Width.
[Zoning Order §7.250, 4-2-2008; Ord. No. 11-12-2008A §§1 — 2(7.250), 11-12-2008; Resolution 1-14-2010A Exh. A, 1-14-2010; Ord. No. 10-0145 §§1 — 2, 2-18-2010]
Below are the standards for the minimum and maximum width of drives and driveways for multi-family residential and non-residential uses, subject to approval of the applicable State or County agency. For one- and two-family developments, the maximum driveway width at the right-of-way line (exclusive of radii at the corners) is twenty-four (24) feet. Type of developments for driveway requirements are based upon the daily traffic volume in Table 7-7 and shall be designed as follows:
Table 7-11. Minimum and Maximum Width of Driveway by Type and Volume of Use (excluding radii) for Multi-Family Residential and Non-Residential Uses | ||
|---|---|---|
Type of Development | Minimum Width | Maximum Width |
Multi-Family Residential | ||
One-way access | Per plan | 30' |
Two-way access | Per plan | 39' |
Low Volume | ||
One-way access | 20' * | 20' * |
Two-way access | 26' ** | 42' ** |
Medium Volume | ||
One-way access | 20' * | 30' ** |
Two-way access | 36' *** | 54' **** |
High Volume/Heavy Industrial | ||
One-way access | 24' * | 30' * |
Two-way access | 36' *** | 60' ***** |
* | One lane |
** | Two lane |
*** | Three lane |
**** | Four lane |
***** | Five lane |
The minimum width for a driveway required by Table 7-11 shall extend the entire throat length as required per Section 400.2630. |
|---|
Where non-residential or multi-family residential developments enter onto a State or County maintained street, the entrance pavement that is located in the State or County right-of-way is subject to Section 400.2560, Street Standards — Minimum Pavement Standards for pavement thickness and Section 400.2610, Driveway Requirements — Width for pavement width. |
Section 400.2620 Driveway Requirements - Corner Clearance.
[Zoning Order §7.260, 4-2-2008; Resolution 1-14-2010A Exh. A, 1-14-2010; Ord. No. 10-0145 §§1 — 2, 2-18-2010; Ord. No. 16-0100 §2, 1-4-2016]
Driveway corner clearance is the distance between a street and the first (1st) driveway accessing a street classified below intersecting with the street. For street corner clearance affecting State or Federally maintained streets, MoDOT and/or Federal Highway (FHWA) standards shall be used. For other scenarios, Table 7-12 provides guidance on the required driveway corner clearance.
Table 7-12. Driveway Corner Clearance | ||
|---|---|---|
Type of Street | "RA-5", "LR-2", "R-40", "R-20", "R-7", "R-10", "PM", "PR-1", "PR-2" | "NC-1", "PC", "CC-2", "PB", "NPI, "PI" |
County | 125' | 125' |
Major local access | None | 50' |
Local access | None | 40' |
Local alley access | None | 30' |
Corner clearance shall be measured from the edge of the travel lane to the edge of driveway. |
Figure 7-6 Driveway Corner Clearance |
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 |
Section 400.2630 Driveway Requirements - Throat Length.
[Zoning Order §7.270, 4-2-2008; Resolution 1-14-2010A Exh. A, 1-14-2010; Ord. No. 10-0145 §§1 — 2, 2-18-2010]
A.
The throat length is the driveway distance between the street and the parking lot served or the first (1st) accessible interior drive. An adequate throat length helps to keep traffic conflicts within a parking lot to a minimum and provides space on the driveway for incoming and outbound traffic.
1.
Low traffic volume non-residential and multi-family residential driveways (below one hundred fifty (150) peak hour vehicles in both directions): The minimum throat length is twenty (20) feet.
2.
Medium traffic volume non-residential and multi-family residential driveways (one hundred fifty (150) to four hundred (400) peak hour vehicles in both directions): The minimum throat length is forty (40) feet.
3.
High traffic volume non-residential and multi-family residential driveways (over four hundred (400) peak hour vehicles in both directions): The minimum throat length is sixty (60) feet.
Figure 7-7 Throat Length | |
|---|---|
 |
Section 400.2640 Sidewalk Requirements.
[Zoning Order §7.280, 4-2-2008; Ord. No. 16-0100 §2, 1-4-2016]
Sidewalks requirements shall be based on the need for sidewalks in the area as well as maintaining and extending existing sidewalk networks. Sidewalks shall at a minimum be constructed in the following areas:
Table 7-13. Sidewalk Requirements | ||
|---|---|---|
Type of Street | Zoning | Sidewalk Requirement |
Local access alley | All zones | None |
Local access street | Residential built at 1 unit (or less) per acre | None |
Residential built at more than 1 unit per acre | One side of street | |
"PR-1", "PR-2" | Per plan | |
"NC-1", "CC-2" | Both sides of street | |
"PC", "PM", "PB" | Per plan | |
"NPI" | None | |
"PI" | Per plan | |
Major local access street | Residential built at 1 unit (or less) per acre | None |
Residential built at more than 1 units per acre | Both sides of street | |
"PR-1", "PR-2" | Per plan | |
"NC-1", "CC-2" | Both sides of street | |
"PC", "PM", "PB" | Per plan | |
"NPI", "PI" | None | |
Sidewalks shall be constructed of concrete five (5) feet wide unless otherwise specified in this Article. |
Section 400.2650 (Reserved) [1]
[1]
Editor’s Note: Former Section 400.2650, Right-Of-Way Dedication Requirements, was repealed 2-14-2017 by Ord. No. 17-0158.
Section 400.2680 Application.
[Zoning Order §7.320, 4-2-2008]
A.
The open space and density bonus standards are used to help preserve natural open space, improve and enlarge open space and provide community facilities while allowing an area to be developed to its full potential. These standards apply to single-family developments, only in the following zoning districts: "RA-5", "LR-2", "R-40", "R-20" and "R-10".
B.
In developments where the density bonus calculation is used and land or facility is proposed to be dedicated to either a public or private entity, such bonus shall not be granted until the public or private entity has demonstrated formal approval/acceptance and agrees to maintenance of the dedication of land or facility. The boundary of the dedicated area/facility shall be recorded with the Jefferson County Recorder of Deeds. Any proposed building or facility must meet all applicable building codes.
Section 400.2690 Definitions.
[Zoning Order §7.330, 4-2-2008]
As used in this Article, the following terms shall have these prescribed meanings:
Land within or related to a development, not individually owned, that is designed and intended for the common enjoyment of the residents of the development and their guests. Common ground may or may not be designated for public use, shall have ownership and maintenance responsibilities recorded in the restrictive covenants of the property owners' association and may include structures and improvements. (Also called common open space)
A facility provided to a property owners or homeowners' association for use according to the covenants of the association and located on the same site of the proposed development. Such facility may be a: golf course, tennis court, swimming pool, athletic field with standards, community or recreation center or equipped playground.
A building provided to a public or taxing entity for use within their jurisdiction. Such building may be a: firehouse, ambulance station, water tower or similar qualifying structure, library or school facility (administrative or classroom). The dedicated public building should be located within the same jurisdiction as the proposed development. A dedicated public building also includes off-site improvement(s) to a publicly owned or maintained expressway, arterial or collector not required as part of the development approval. The value of such improvement(s) shall equal or exceed fifty percent (50%) of the value of the street improvements within the development.
A parcel of land provided for use by a local, County, State or Federal conservation agency or organization. A non-profit organization may qualify as the recipient of a dedicated public land if the non-profit organization's recorded deed of ownership guarantees the public land remain in perpetuity.
A parcel of land provided to a local government for use as a park. Such park should be a minimum of five (5) acres in size and shall include infrastructure and park improvements acceptable to the receiving entity installed at the time of dedication. The dedicated public park shall be located within a five (5) mile radius of the jurisdictional limits of the receiving entity.
An accessible, undeveloped area in a development plan or subdivision plat where physical constraints or lack of infrastructure (present and future) do not preclude development of home sites and the area has been set aside as open space/common ground in addition to the required open space for the development. The minimum total area of developable open space shall be five percent (5%) of the gross acreage of the development site.
An area of land or water, essentially unimproved and set aside, dedicated, designated or reserved for public or private use or enjoyment.
An area of a development plan or preliminary plat where a community of plants no longer exists and the area will be planted with trees or other secondary succession plants in addition to the required open space for the development. The minimum total area of a restored land project should be six (6) acres.
The number of dwelling units per acre on a particular site (see Section 400.2700(A)).
Section 400.2700 Density Calculations.
[Zoning Order §7.340, 4-2-2008]
B.
The open space design table, Table 7-15, specifies minimum lot sizes based on the amount of open space set aside, dedicated, designated or reserved at the site on the development plan or preliminary plat.
C.
A lot density bonus may be available for a site based on the minimum standards in Table 7-16 through provision of a dedicated private recreation facility, dedicated public building, dedicated park, dedicated public land or restored public or private land.
D.
Further reduction in minimum lot size may be available for provision of a dedicated undeveloped developable space. The maximum additional reduction in lot size under this provision is five percent (5%).
Section 400.2710 Open Space and Density Bonus Tables.
[Zoning Order §7.350, 4-2-2008]
Table 7-15. Open Space Design Calculation | ||||||
|---|---|---|---|---|---|---|
Zoning District | Units/ Acres | Min. Lot Size | 20% Open Space | 30% Open Space | 40% Open Space | 50% Open Space |
"RA-5" | 1 per 5 acres | 5 acres | 4 acres | 3 acres | 2 acres | 1 acre |
"LR-2" | 1 per 2 acres | 2 acres | 60,000 sf | 40,000 sf | 30,000 sf | 20,000 sf |
"R-40" | 1 per 1 acre | 1 acre | 32,000 sf | 28,000 sf | 24,000 sf | 18,000 sf |
"R-20" | 2 per 1 acre | 20,000 sf | 16,000 sf | 14,000 sf | 11,000 sf | 9,000 sf |
"R-10" | 4 per 1 acre | 10,000 sf | 9,000 sf | 8,000 sf | 7,000 sf | 6,500 sf |
sf = square feet | ||||||
Setback Reduction When Using Open Space Design Calculation. Front and rear yard setbacks for lots utilizing the open space design standard may be reduced up to the same percentage of open space dedicated. For example, the setbacks for a lot in the "R-20" District are thirty (30) feet for the front yard and thirty (30) feet in the rear yard. If an "R-20" development utilizes the open space design and dedicates fifty percent (50%) to open space, then the front and rear yard setbacks could be reduced up to fifty percent (50%); therefore having fifteen (15) foot front yard setbacks and fifteen (15) foot rear yard setbacks. No reduction is permitted in the side yard setback. |
Minimum Lot Width Reduction When Using Open Space Design Calculation. The minimum lot width for lot sizes less than ten thousand (10,000) square feet when using the open space design calculation may be reduced to thirty-five (35) feet. |
Table 7-16. Density Bonus Calculation | ||||||||
|---|---|---|---|---|---|---|---|---|
Dedicated Public Land Bonus | ||||||||
Zoning District | Dedicated Private Recreation Facility Bonus | Dedicated Public Building Bonus | 20 or more acres | Less than 20 acres | Dedicated Public Park Bonus | Restored Public or Private Land Bonus | Un-developed Develop-able Space Bonus | Maximum Total Bonus |
Table 7-16. Density Bonus Calculation | ||||||||
"RA-5" | 5% | 10% | 10% | 5% | 10% | 5% | 0% | 40% |
"LR-2" | 5% | 10% | 10% | 5% | 10% | 5% | 0% | 40% |
"R-40" | 5% | 5% | 5% | 1% | 5% | 5% | 5% | 30% |
"R-20" | 5% | 5% | 5% | 1% | 5% | 5% | 5% | 30% |
"R-10" | 5% | 5% | 5% | 1% | 5% | 5% | 5% | 30% |
Figure 7-8 Open Space Design and Density Bonus — Example | |
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The following is an example of how Division 9, Open Space Design and Density Bonus Standards, should work: | |
A developer proposes to plat one hundred (100) acres that is zoned "R-20" District. This district has a minimum lot size of twenty thousand (20,000) square feet, a density of two (2) lots per acre. The total lot count is therefore a maximum of two hundred (200) lots. | |
The developer chooses an open space design under Table 7-15. Thirty percent (30%) dedicated open space can be provided. This will allow a reduction of lot sizes to fourteen thousand (14,000) square feet minimum, but does not allow any increase in lot count. The total number of lots available remains at two hundred (200). | |
The developer also chooses a public dedication under Table 7-16. Suppose five (5) acres are dedicated for a public park. This dedication is rewarded with a five percent (5%) increase in lot density. The developer also chooses to construct a park shelter building with running water and toilet facilities. This dedication is rewarded with a five percent (5%) increase in lot density. Now, multiply the permitted number of lots from above by ten percent (10%) for the two (2) five percent (5%) dedications. [200 X 10% = 20]. Therefore, for these public dedications, the development is allowed to increase lot count to a maximum of two hundred twenty (220) lots. | |