A. Applicants proposing regulated activities in the City of Reading which do not fall under the exemption criteria shown in § 505-142 shall submit a drainage plan consistent with the applicable (Schuylkill River or Tulpehocken Creek) stormwater management plan to the municipality for review. These criteria shall apply to the total proposed development even if development is to take place in stages.
B. The applicant is required to evaluate practicable alternatives to the surface discharge of stormwater, the creation of impervious surfaces and the degradation of waters of the commonwealth, and must maintain as much as possible the natural hydrologic regime.
C. The drainage plan must be designed consistent with the sequencing provisions of § 505-124 to ensure maintenance of the natural hydrologic regime and to promote groundwater recharge where appropriate and to protect groundwater and surface water quality and quantity. The drainage plan designer must proceed sequentially in accordance with Subpart C of this Part.
D. Stormwater drainage systems shall be provided in order to permit unimpeded flow along natural watercourses, except as modified by stormwater management facilities or open channels consistent with this Part.
E. Existing points of concentrated drainage that discharge onto adjacent property shall not be altered in any manner which could cause property damage without permission of the affected property owner(s) and shall be subject to any applicable discharge criteria specified in this Part.
F. Areas of existing diffused drainage discharge shall be subject to any applicable discharge criteria in the general direction of existing discharge, whether proposed to be concentrated or maintained as diffused drainage areas, except as otherwise provided by this Part. If diffused drainage discharge is proposed to be concentrated and discharged onto adjacent property, the applicant must document that adequate downstream conveyance facilities exist to safely transport the concentrated discharge, or otherwise prove that no erosion, sedimentation, flooding or other impacts will result from the concentrated discharge.
G. Where a development site is traversed by existing watercourses, drainage easements shall be provided conforming to the line of such watercourses. The terms of the easement shall conform to the stream buffer requirements contained in § 505-126B(6) of this Part.
H. Any stormwater management facilities regulated by this Part that would be located in or adjacent to waters of the commonwealth or wetlands shall be subject to approval by PaDEP through the joint permit application process, or, where deemed appropriate by PaDEP, the general permit process. When there is a question whether wetlands may be involved, it is the responsibility of the applicant or his agent to show that the land in question cannot be classified as wetlands; otherwise, approval to work in the area must be obtained from PaDEP.
I. Any stormwater management facilities regulated by this Part that would be located on state highway rights-of-way shall be subject to approval by the Pennsylvania Department of Transportation (PennDOT).
J. Minimization of impervious surfaces and infiltration of runoff through seepage beds, infiltration trenches, etc., are encouraged, where soil conditions permit, to reduce the size or eliminate the need for detention facilities or other structural BMPs.
K. Roof drains shall not be connected to streets, sanitary or storm sewers or roadside ditches in order to promote overland flow and infiltration/percolation of stormwater where advantageous to do so. When it is more advantageous to connect directly to streets or storm sewers, then it shall be permitted on a case-by-case basis by the municipality.
L. All stormwater runoff shall be pretreated for water quality prior to discharge to surface or groundwater.
M. All regulated earth disturbance activities within the municipality shall be designed, implemented, operated and maintained to meet the purposes of this Part, through these two elements:
(1) Erosion and sediment control during the earth disturbance activities (e.g., during construction).
(2) Water quality protection measures after completion of earth disturbance activities (i.e., after construction), including operations and maintenance.
N. No regulated earth disturbance activities within the municipality shall commence until the requirements of this Part are met.
O. Postconstruction water quality protection shall be addressed as required by § 505-126.
P. Operations and maintenance of permanent stormwater BMPs shall be addressed as required by Subpart G.
Q. All best management practices (BMPs) used to meet the requirements of this Part shall conform to the state water quality requirements, and any more stringent requirements as determined by the municipality.
R. Techniques described in Appendix E of this Part (Low-Impact Development)
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are encouraged, because they reduce the costs of complying with the requirements of this Part and the state water quality requirements.
S. In selecting the appropriate BMPs or combinations thereof, the applicant shall consider the following:
(1) Total contributing area.
(2) Permeability and infiltration rate of the site soils.
(3) Slope and depth to bedrock.
(4) Seasonal high water table.
(5) Proximity to building foundations and wellheads.
(6) Erodibility of soils.
(7) Land availability and configuration of the topography.
(8) Peak discharge and required volume control.
(9) Stream bank erosion.
(10) Efficiency of the BMPs to mitigate potential water quality problems.
(11) The volume of runoff that will be effectively treated.
(12) The nature of the pollutant(s) being removed.
(13) Maintenance requirements.
(14) Creation/protection of aquatic and wildlife habitat.
(15) Recreational value.
T. Transference of runoff from one DEP designated Act 167 watershed to another shall be prohibited.
8. Editor's Note: Appendix E is included at the end of this chapter.