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)
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)
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)
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:
a. Deterioration of existing culverts, bridges, dams, and other structures.
b. Exceeding capacity of existing stormwater facilities.
c. Accelerated streambank or streambed erosion or siltation.
d. Increased threat of flood damage to public health, life and property.
(Ord. 2006-11 § 1, 2006; Ord. 2009-05 § 1, 2009)