Port Orford City Zoning Code
CHAPTER 17
18 STORM AND SURFACE WATER MANAGEMENT
§ 17.18.005 Purpose and objective.
The purpose of this chapter is to promote the general health, safety, welfare, and economic well being of the community by maintaining good water quality for the ecosystem both on land and at sea. The objective is to preserve the predevelopment discharge rate and volume to the maximum extent practicable by:
A.
Minimizing increases in stormwater runoff rates and volume from any development in order to reduce flooding, siltation and streambank erosion, and maintain the integrity of riparian areas.
B.
Minimizing increases in nonpoint source pollution caused by stormwater runoff from development which could otherwise degrade local water quality.
C.
Reducing stormwater runoff rates and volume, soil erosion and nonpoint source pollution, wherever practical, through stormwater management controls such as best management practices and low impact development strategies except where an approved variance is granted pursuant to the standards of this ordinance.
D.
Encouraging use of best management practices, which may best address water quality indicators of concern as identified by the Oregon Department of Environmental Quality in Total Maximum Daily Loads (TMDL) provisions or otherwise implementing the Federal Clean Water Act.
E.
Utilizing vegetation for stormwater management when and where feasible.
(Ord. 2009-05 § 1, 2009)
§ 17.18.010 Definitions.
A.
Terms not defined in this section shall have the common usage or as defined in the City of Port Orford Design Standards (Engineering Standards), or those listed by the United States Environmental Protections Agency's National Pollutant Discharge Elimination System or the Oregon Department of Environmental Quality.
B. "Best management practices (BMPs)," "Develop" "Impervious areas/impervious surface" "Low impact development (LID)" "Pollutants or indicators of concern"
The following definitions shall be applicable to this chapter unless otherwise stated:
as defined in the City of Port Orford Design Standards (Engineering Standards) document means a physical, chemical, structural or managerial practice that prevents, reduces, or treats the contamination of water, or which prevents or reduces soil erosion.
means to construct or alter a structure or to make a physical change to the land including excavations and fills.
means any surface which either prevents or retards absorption or infiltration of water into the land surface, as existed under natural conditions prior to development that causes water to run off the land surface in concentrated quantities or at an increased rate of flow. Impervious areas include, but are not limited to, parking lots and other paved areas, paved roads, compacted soil, structures, and roofs.
as described by the U.S. Environmental Protection Agency and/or the Oregon Department of Environmental Quality is an approach to land development or redevelopment that works with nature to manage stormwater as close to its source as possible. LID employs principles such as preserving and recreating natural landscape features, minimizing effective imperviousness to create functional and appealing site drainage that treats stormwater as a resource rather than a waste product. Examples include bioretention facilities, rain gardens, vegetated rooftops, rain barrels, and permeable pavements that can reduce the impact of built areas and promote the natural movement of water within an ecosystem or watershed.
are watershed-specific parameters identified by the Oregon Department of Environmental Quality (DEQ) as having a negative impact on the receiving water body. Pollutants of concern can include, but are not limited to, increased stormwater discharge rates, suspended solids, heavy metals, nutrients, bacteria and viruses, organics, volatiles, semivolatiles, floatable debris and increased temperature.
(Ord. 2009-05 § 1, 2009)
§ 17.18.020 Applicability.
A.
This chapter applies to lands within the City of Port Orford at the time of application to the City for a building permit or access permit, or in the case of City property or development of infrastructure, prior to the development of new impervious surface.
B.
This chapter works in coordination with the City of Port Orford Design Standards (Engineering Standards), but this chapter is applicable to all properties and uses, whether or not the Engineering Standards apply.
C.
Building permits and right-of-way usage permits may only be granted by the City of Port Orford when it has been determined that there is compliance with the requirements of this chapter.
D.
This chapter creates two land use groups with separate requirements that are determined by use and size.
1.
Group One uses are defined as:
a.
New residential construction under 3,000 square feet in size, including single-family dwelling or duplex, manufactured home, childcare facility, residential care home and residential care facility.
b.
New additions to existing single-family dwelling or duplex, manufactured home, childcare facility, residential care home and residential care facility which create new impervious surface of less than 3,000 square feet.
c.
New development or construction, not otherwise included in Group Two, requiring a building permit or driveway access permit which will create new impervious area less than 3,000 square feet.
2.
Group Two uses are defined as:
a.
Master planned areas where a number of homes are to be constructed by one developer prior to sale of the lots, new subdivisions and planned unit developments.
b.
Commercial development and/or construction.
c.
Multi-family residential.
d.
New residential construction that is 3,000 square feet or greater in size, including single-family dwelling or duplex, manufactured home, childcare facility, residential care home and residential care facility.
e.
Industrial development and/or construction.
f.
New additions to any existing structures which will create new impervious area that is 3,000 square feet or greater.
g.
New development or construction requiring a building permit or driveway access permit which will create new impervious area that is 3,000 square feet or greater.
h.
Public works projects, including structures and impervious surfaces such as off-street parking areas or public roads which create impervious surface of 3,000 square feet or greater.
(Ord. 2009-05 § 1, 2009)
§ 17.18.030 Applications.
All applicants for building permits and access permits shall provide calculations of new impervious surface generated as defined by this chapter at the time of application for building or access permits. Drawings submitted for building permits shall identify stormwater infiltration locations.
(Ord. 2009-05 § 1, 2009)
§ 17.18.040 General requirements-Group One.
The intent of this section is to prevent water from private property from flowing into the right-of-way or endangering adjacent properties or natural resources.
A.
Standards. Stormwater from new impervious area generated from structures including, but not limited to, roofs, and impervious paved areas shall be directed away from driveways or public or private streets or rights-of-way and wetland areas. Stormwater may be captured through gutters and downspouts and directed to vegetated areas away from on-site structures and away from neighboring properties through one of the following methods:
1.
Required setback areas between any specific structure and the right-of-way or other property lines are appropriate discharge locations provided the setback dimensions accommodate all generated stormwater through infiltration and do not cause runoff on neighboring properties.
2.
Native vegetation is recommended in close proximity to downspout areas to increase infiltration and pollutant removal. Other methods of stormwater capture, direction and infiltration such as turf grass or other vegetations are acceptable provided that there is compliance with this section.
3.
Stormwater generated by driveways may be directed to the side of the driveway by slanting driveways so water flows to one side, or crowning driveways so water flows to both sides. Other measures used in conjunction with sheet flow directional measures or pervious surfaces may also be used to fulfill the provisions of this section when there is compliance with the intent of this subsection A, and provided that stormwater empties into pervious and vegetated areas.
4.
Stormwater facilities that comply with Group Two requirements may be utilized to satisfy Group One requirements.
B.
Variances to Standards. Requests for variances from Group One requirements in this section may be considered by the Planning Commission in compliance with the procedures of Chapter 17.36 and Section 17.18.060 of this chapter. Requests may be considered without a report from the City Engineer, but the Planning Commission, at their own discretion, may request a report from the City Engineer to assist the Planning Commission in making their decision.
(Ord. 2009-05 § 1, 2009)
§ 17.18.050 General requirements-Group Two.
A.
Where Group Two Requirements Apply. The City Engineer shall review the application and require one of the following:
B.
Stormwater Plan Submittal. The applicant shall provide a stormwater management plan whereby storm/surface water within the development will be managed without causing damage or harm to the natural environment, or to property or person, and to protect property from flood hazards to the maximum extent possible.
D.
Facility Location. Required setback areas between the structure and the right-of-way or other property lines are appropriate locations for stormwater management facilities provided that the stormwater management facilities are not "structures" as defined in Section 17.04.030 of this title and are not deemed by the City Engineer to interfere with, damage or endanger adjacent properties, or rights-of-way and associated infrastructure.
E.
Review Process. Applications shall be reviewed by the City Engineer who shall approve, approve with conditions, or deny based upon analysis and preparation of written findings that will be maintained in the record. When there is compliance the City Engineer shall provide a certification of compliance. Decisions of the City Engineer may be appealed to the Planning Commission.
F.
Appeal Process. Appeals to the Planning Commission shall include the City Engineer's written findings, and analysis provided by the applicant showing where the findings and decision are in error.
(Ord. 2009-05 § 1, 2009)
§ 17.18.060 Variances.
Variances to the standards of this chapter shall be determined by the Planning Commission subject to the procedures set forth in Chapter 17.36, utilizing the criteria set forth in subsections A and B and Section 17.36.030(B) and (C). The Planning Commission may approve, approve with conditions, or deny the variance.
A.
Application. The applicant shall submit an application showing that there is compliance with at least one of the following conditions and with the criteria of Section 17.36.030(B) and (C).
1.
The site has high groundwater, poor infiltration rates, geologic or hydrogeologic constraints, or steep slope conditions. The City may require a professional geotechnical engineer or certified engineering geologist to demonstrate and recommend that this exception applies to the specific site.
2.
Contamination is present at the site, as determined by DEQ or a registered environmental engineer. Sites that have contaminated soils conditions must be evaluated in accordance with DEQ criteria to determine if areas on the property are suitable for infiltration without the risk of mobilizing contaminants in the soil or groundwater. Documentation showing DEQ's approval of the contamination assessment and determination must be submitted to the City at the time of permit application.
3.
On-site space constraints prohibit the construction of on-site infiltration facilities. Maximum density allowed by the zoning code does not exempt the applicant from stormwater requirements. Technical requirements for applicable stormwater infrastructure compliant with the intent of this chapter must be approved prior to the approval of building or access permits.
4.
The proposed development or associated stormwater facilities are within 500 feet of a wellhead.
5.
Other circumstances related to the property, which are not caused by the owner or foreseen by this chapter.
B.
Criteria for Approval. When approving a variance subject to this section, any decision to approve the variance shall be based upon findings that the following conditions have been met.
1.
Approval is not likely to impair attainment of the purpose, objectives or standards of Section 17.18.005 Purpose and objective, of this chapter, the City's most current stormwater management plan, or the City of Port Orford Design Standards (Engineering Standards); or
2.
Alternative on-site stormwater management measures have been proposed that meet the purposes of Section 17.18.005; or
3.
Provisions are made to manage stormwater by an off-site facility. The off-site facility is required to be in place and adequately sized to comply with the City of Port Orford Design Standards (Engineering Standards) and to provide a level of stormwater control that is equal to or greater than that which would be afforded by on-site practices with a legally obligated entity responsible for long-term operation and maintenance of the stormwater; or
4.
Non-structural practices are used on the site that significantly reduce: (a) the generation of storm-water from the site, (b) the rate (speed) of runoff leaving the site, and (c) the pollutants generated at the site; or
5.
Complying with the minimum on-site management requirements is not feasible due to the nature or existing physical characteristics of a site and that there is a supporting statement from a registered engineer or geologist; or
6.
The variance will not threaten public health or safety; or
7.
Findings shall be made that the approval of this variance shall not result in any of the following:
(Ord. 2006-11 § 1, 2006; Ord. 2009-05 § 1, 2009)