A.Â
No development plan, subdivision plat or land development plan shall
be approved; no permit authorizing construction or development issued;
nor any earth disturbance activity subject to this article shall be
initiated or undertaken unless and until a stormwater management plan
for such activity is reviewed and approved in accord with the provisions
of this chapter.
B.Â
No regulated development activities within the Township shall commence until approval by the Township of a stormwater management plan which demonstrates compliance with state water quality requirements after construction is complete. Reference should be made to the Regulated Development Activity Table located in Article III of this chapter.
C.Â
The stormwater management plan must be designed, implemented and
maintained to meet state water quality requirements, and any other
more stringent requirements as determined by the Township.
D.Â
To control post-construction stormwater impacts from regulated development
activities, state water quality requirements can be met by BMPs, including
site design and green infrastructure, which provide for replication
of pre-construction stormwater infiltration and runoff conditions,
so that post-construction stormwater discharges do not degrade the
physical, chemical or biological characteristics of the receiving
waters. As described in the DEP Comprehensive Stormwater Management
Policy (#392-0300-002, September 28, 2002), this may be achieved by
implementation of the following:
(1)Â
Infiltration. Replication of pre-construction stormwater infiltration
conditions.
(2)Â
Treatment. Use of water quality treatment BMPs to ensure filtering
out of the chemical and physical pollutants from the stormwater runoff.
(3)Â
Stream bank and streambed protection. Management of volume and rate
of post-construction stormwater discharges, using detention/retention
and other means, to prevent physical degradation of receiving waters
(e.g., from scouring).
E.Â
Where an existing stormwater conveyance method or easement, whether
natural or man-made, for release of stormwater flow from a development
site does not exist, an easement for the off-site conveyance must
be provided. Information shall be presented as to the ownership, sufficient
for the Township to identify the owner of the property and the person
responsible for the construction and/or maintenance of same. A copy
of an executed agreement and recorded deed for the conveyance of said
easement must be provided to the Township.
F.Â
The stormwater management plan must meet DEP regulations requiring
municipalities to ensure design, implementation and maintenance of
best management practices (BMPs) to control runoff from both new development
and redevelopment after regulated development activities are complete.
These requirements include the need to implement post-construction
stormwater facilities and BMPs along with assurances for the long-term
operation and maintenance of those BMPs.
G.Â
Evidence of the issuance of necessary third-party permits, such as
Chapter 102, erosion and sedimentation control[1] or Chapter 105, stream encroachment,[2] for regulated development activities from WCD or the appropriate
DEP regional office, must be provided to the Township. The issuance
of an NPDES construction permit [or permit coverage under the Statewide
General Permit (PAG-2)] may be deemed by the Township to satisfy all
or portions of the Stormwater Management Plan requirements of this
chapter.
I.Â
The Township shall not approve any Stormwater Management Plan that
does not meet the requirements of this chapter. At its sole discretion
and in accordance with this chapter, when a SWM Plan is found to be
deficient, the Township may either disapprove the submission and require
a resubmission, or in the case of minor deficiencies, the Township
may accept submission of modifications.
J.Â
The stormwater management plan (including all calculations) must
be prepared, certified and sealed by a qualified professional with
training and expertise in hydrology and hydraulics. Documentation
of qualifications of the qualified professional may be required by
the Township.
A.Â
General format. The stormwater management plan shall include a narrative
and a set of plan drawings. Reference should be made to the checklist
contained in Appendix F.[1]
[1]
Editor's Note: Appendix F is included as an attachment to this chapter.
B.Â
The narrative describing the overall stormwater management concept
for the project must include:
(1)Â
A determination of site conditions in accordance with the PA DEP
Stormwater BMP Manual. A detailed site evaluation shall be completed
for a project's proposed environmentally sensitive areas, such
as brownfields.
(2)Â
Stormwater runoff design calculations determining pre- and post-development discharge rates for the design of proposed stormwater control facilities sufficient to demonstrate that the maximum practicable measures have been taken to meet the requirements of this chapter must be submitted with the Stormwater Management Plan. All calculations shall be prepared using the methods and data prescribed by general requirements in § 99-15 above. Reference should also be made to the Acceptable Computation Methodologies for Stormwater Management Plans table in § 99-19 of this chapter.
(b)Â
Detention/retention requirements, including volume, routing,
etc., for BMPs shall be calculated using commonly acceptable standard
methods.
(c)Â
Water quality calculations shall be determined by using the
PA DEP Stormwater BMP Manual 2006 or current edition Worksheets 12
and 13 or another alternative method acceptable to the Township.
(3)Â
An expected project time schedule for the installation of all temporary
and permanent stormwater control measures and devices. If the development
is to be constructed in stages, the applicant must describe how stormwater
facilities and BMPs will be sequentially installed to manage stormwater
runoff safely during each stage of development.
(4)Â
A statement of the effect of the project (in terms of runoff rate,
volumes, and water quality) on surrounding properties, aquatic features
and on any existing stormwater conveyance system that may be affected
by the project.
(5)Â
If appropriate, the narrative should provide justification as to
why any preferred stormwater management techniques, such as LID and
green infrastructure, as listed in this chapter, are not proposed
for use. Reference should be made to the PA DEP Stormwater BMP Manual
2006 or most recent edition for list of acceptable management techniques.
C.Â
The stormwater management plan drawings shall be drawn to a scale
of not less than one inch equals 100 feet. All sheets shall contain
a title block with the name and address of the applicant and designer,
the scale, North arrow, legend and date of preparation and, where
applicable, the date of any revision. The Stormwater Management Plan
drawings shall identify and locate the following:
(1)Â
Existing and proposed features:
(a)Â
Watershed location. Provide a key map (using USGS Topo maps)
showing the location of the development site within the watershed(s)
and watershed subarea(s). On all site drawings, show the boundaries
of the watershed(s) and subarea(s) as they are located on the development
site and identify watershed name(s) and subarea number(s). Refer to
Appendix A Watershed Performance District Maps.[3]
[3]
Editor's Note: Appendix A is included as an attachment to this chapter.
(b)Â
Floodplain boundaries. Identify one-hundred-year floodplains
on the development site (as appropriate) based on the FEMA Flood Insurance
Rate Map(s) for the Township.
(c)Â
Natural features. Show all bodies of water (natural or artificial),
watercourses (permanent and intermittent), swales, wetlands and other
natural drainage courses on the development site, or which will be
affected by runoff from the development.
(d)Â
Soils. Provide an overlay showing soil types and boundaries
within the development site (consult WCD, SCS and U.S. Geological
Survey for information).
(e)Â
Contours. Show existing and final contours at intervals of two
feet; in areas with slopes greater than 15%, five-foot contour intervals
may be used.
(f)Â
Land cover. Show existing and final land cover classifications,
including existing and proposed improvements, as necessary to support
and illustrate the runoff calculations performed.
(g)Â
Drainage area delineations. Show the boundaries of the drainage
areas and points of interest employed in the runoff calculations performed.
(h)Â
Time of concentration flow paths. Show flow paths used for all
time of concentration calculations. Identify the different segments
of flow path used for travel time calculations for sheet flow, shallow
concentrated flow and channel flow regimes.
(i)Â
Utilities and easements. Show any existing utilities, stormwater
management or drainage controls and/or structures, such as sanitary
sewers, water, gas, electric, telecommunications, storm sewers, swales,
culverts, and any easements, which are located on the development
site, or which are off site but may be affected by runoff from the
development.
(2)Â
Proposed stormwater facilities and BMPs. All proposed stormwater
runoff control measures must be shown on the plan, including methods
for collecting, conveying and storing stormwater runoff on site, which
are to be used both during and after construction. Erosion and sedimentation
controls shall be shown in accordance with applicable Township and
WCD requirements. The plan shall provide information on the exact
type, location, sizing, design and construction of all proposed facilities
and relationship to the existing watershed drainage system.
(a)Â
If the development is to be constructed in stages, the applicant
must demonstrate that stormwater facilities will be installed to manage
stormwater runoff safely during each stage of development.
(b)Â
A schedule for the installation of all temporary and permanent
stormwater control measures and devices shall be included in the narrative
and shown on the site plan. This schedule shall include all stages
of construction identified as critical for the proper short-term and
long-term operation and performance of these control measures that
will need to be inspected by the stormwater design engineer, the Township
Engineer and/or the WCD.
(3)Â
Easements, rights-of-way, deed restrictions. BMPS and stormwater
management facilities that provide control for more than one lot shall
be located on a separate dedicated lot or provided for through an
easement on the property upon which it is located. All existing and
proposed easements for any BMPs, stormwater management facilities
and controls for access, inspections, maintenance, repair, preservation
and use shall be shown on the plan and, if required, dedicated to
the entity, association or person responsible for the continuing operation
and maintenance of same. The easement and the purpose for the same
shall be set forth on the plan and in the agreement required by the
chapter.
A list of any approvals/permits relative to stormwater management
that will be required from other governmental agencies (e.g., Chapter
102 Erosion and Sediment Control, PennDOT Highway Occupancy Permit,
Chapter 105 Water Obstruction and Encroachment Permit from PA DEP)
and the anticipated dates of submission/receipt should be included
with the stormwater plan submission. Copies of permit applications
may be requested by the Township to assist in the plan review.
The application shall contain a proposed Operation and Maintenance (O&M) Plan for all stormwater control facilities as described in Article VI of this chapter. Such plan shall:
A.Â
Identify the party responsible for the operation, maintenance and
control of the stormwater facilities and their responsibilities (e.g.,
the Township, property owner, private corporation, homeowners' association
or other entity).
B.Â
Include an operation and maintenance plan for all stormwater facilities
outlining the routine maintenance actions and schedules necessary
to ensure proper operation of the stormwater control facilities.
C.Â
Identify and attach any legal agreements required to implement the
maintenance program and copies of the maintenance agreement as required
by this chapter.
D.Â
Identify method of financing continuing operation and maintenance
if the facility is to be owned by a person or entity other than the
Township or a governmental agency.
Financial guarantees, in a form acceptable to the Township,
shall be submitted by the developer for the construction and maintenance
of the project as well as the construction, operation and maintenance
of any stormwater management BMPs, regardless of whether the stormwater
management BMPs or other stormwater management facilities are dedicated
to the Township as a public facility or retained privately. In requiring
financial guarantees for privately held facilities, the Township acknowledges
that private ownership, and the responsibility for the continuing
operation and maintenance of stormwater management facilities, may
be compromised by bankruptcy, death or neglect of the person or persons
initially charged with the responsibility for same. In that event,
the Township finds that it is necessary to require long-term financial
guarantees to be posted by the developer to offset the Borough's
costs and expenses it may incur in the event of bankruptcy, death
or neglect of the person or persons initially charged with the responsibility
for such facilities and the protection of the public health, safety
and welfare. All financial guarantees shall be set forth in a BMP
Operation and Maintenance Agreement in the form attached hereto in
Appendix C.[1]
[1]
Editor's Note: Appendix C is included as an attachment to this chapter.