The following permit requirements may apply to certain regulated earth
disturbance activities and must be met prior to commencement of regulated
earth disturbance activities, as applicable:
A. All regulated earth disturbance activities subject to
permit requirements by DEP under regulations at 25 Pennsylvania Code Chapter
102.
B. Work within natural drainageways subject to permit by
DEP under 25 Pennsylvania Code Chapter 105.
C. Any stormwater management facility that would be located
in or adjacent to surface waters of the commonwealth, including wetlands,
subject to permit by DEP under 25 Pennsylvania Code Chapter 105.
D. Any stormwater management facility that would be located
on a state highway right-of-way or require access from a state highway shall
be subject to approval by PennDOT.
E. Culverts, bridges, storm sewers, or any other facilities
which must pass or convey flows from the tributary area and any facility which
may constitute a dam subject to permit by DEP under 25 Pennsylvania Code Chapter
105.
The applicant shall comply with the following water quality requirements
of this article.
A. No regulated earth disturbance activities within the
Municipality shall commence until approval by the Municipality of a plan which
demonstrates compliance with postconstruction state water quality requirements.
B. The BMPs shall be designed, implemented, and maintained
to meet state water quality requirements and any other more stringent requirements
as determined by the Municipality.
C. To control postconstruction stormwater impacts from regulated
earth disturbance activities, state water quality requirements can be met
by BMPs, including site design, which provide for replication of preconstruction
stormwater infiltration and runoff conditions so that postconstruction stormwater
discharges do not degrade the physical, chemical, or biological characteristics
of the receiving waters. As described in the DEP Comprehensive Stormwater
Management Policy (No. 392-0300-002, September 28, 2002), this may be achieved
by the following:
(1) Infiltration: replication of preconstruction stormwater
infiltration conditions;
(2) Treatment: use of water quality treatment BMPs to ensure
filtering out of the chemical and physical pollutants from the stormwater
runoff; and
(3) Stream bank and stream bed protection: management of
volume and rate of postconstruction stormwater discharges to prevent physical
degradation of receiving waters (e.g., from scouring).
D. Developed areas shall provide adequate storage and treatment
facilities necessary to capture and treat stormwater runoff. The retention
volume computed under Section 405 may be a component of the water quality
volume if the applicant chooses to manage both components in a single facility.
If the retention volume is less than the water quality volume, the remaining
water quality volume may be captured and treated by methods other than infiltration
BMPs. The required water quality volume (WQv) is the storage capacity needed
to capture and treat a portion of stormwater runoff from the developed areas
of the site. To achieve this goal, the following criterion is established:
(1) The following calculation formula is to be used to determine
the water quality storage volume (WQv) in acre-feet of storage required by
this chapter:
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WQv = [(P)(Rv)(A)] ÷ 12
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Where:
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WQv
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=
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Water quality volume (acre-feet)
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P
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=
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one inch.
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A
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=
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Area of the project contributing to the water quality BMP (acres).
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Rv
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=
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0.05 + 0.009(I) where I is the percent of the area that is impervious
surface [(impervious area/A)*100].
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(2) This volume requirement can be accomplished by the permanent volume of a wet basin or the detained volume from other BMPs. Where appropriate, wet basins shall be utilized for water quality control and shall follow the guidelines of the BMP manuals referenced in Ordinance
Appendix G.
(3) Release of water can begin at the start of the storm
(i.e., the invert of the water quality orifice is at the invert of the facility).
The design of the facility shall provide for protection from clogging and
unwanted sedimentation.
E. For areas within defined special protection subwatersheds
that include EV and HQ waters, the temperature and quality of water and streams
shall be maintained through the use of temperature sensitive BMPs and stormwater
conveyance systems.
F. To accomplish the above, the applicant shall submit original
and innovative designs to the Borough Engineer for review and approval. Such
designs may achieve the water quality objectives through a combination of
different BMPs.
G. If a perennial or intermittent stream passes through the site, the applicant shall create a stream buffer extending a minimum of 100 feet to either side of the top-of-bank of the channel. The buffer area shall be maintained with and encouraged to use appropriate native vegetation (refer to
Appendix H of the Pennsylvania Handbook of Best Management Practices for Developing Areas for plant lists). If the applicable rear or side yard setback is less than 100 feet, the buffer width may be reduced to a minimum of 75 feet. If an existing buffer is legally prescribed (i.e., deed, covenant, easement, etc.) and it exceeds the requirements of this chapter, the existing buffer shall be maintained. This does not include lakes or wetlands.
H. Evidence of any necessary permit(s) for regulated earth
disturbance activities from the appropriate DEP regional office must be provided
to the Municipality.