A.
The Westmoreland County Integrated Water Resources Plan provides
an online decision-making tool to assist developers, designers, property
owners in addressing all water resources during development and redevelopment
and should be consulted. Reference should be made to www.paiwrp.com
for the decision-making tool and www.westmorelandstormwater.org. Applicants
should also refer to the Westmoreland County Integrated Water Resources
Plan (IWRP) located at www.westmorelandstormwater.org for mapping
of impaired streams, riparian buffers and pollutant loading to determine
appropriate BMPs to address sources of impairments.
B.
Before submitting the stormwater management plan, and any other plan
required by a reviewing agency, applicants are urged to consult with
the Township, Westmoreland County Department of Planning and Development
and Westmoreland Conservation District, and PennDOT, where applicable,
on the requirements for safely managing the development site in a
manner consistent with the Township Code, the terms of this chapter,
any applicable watershed stormwater management plan and federal and
state requirements. These agencies may also be helpful in providing
necessary data for the stormwater management plan.
C.
Applicants are encouraged to submit a sketch plan with a narrative
description of the proposed stormwater management controls for general
guidance and discussion with the Township and other agencies.
D.
The pre-application procedure is not mandatory; any review comments
provided by the Township or other agencies are advisory only and do
not constitute any legally binding action on the part of the Township
or any County agency.
A.
Submission of plans. A stormwater management plan application shall
be submitted with the preliminary and final subdivision/land development
applications or, if no subdivision or land development is involved,
then with the application for development. Copies of the SWM Site
Plan shall also be submitted to the following agencies as determined
by the Township:
(1)
One paper and one digital copy to the Township, in a digital format
acceptable to the Township.
(2)
One copy to the Township Engineer (when applicable).
(3)
One copy to the Westmoreland Conservation District (when applicable).
(4)
One copy to the Unity Township Municipal Authority (when applicable).
(5)
One copy to the Westmoreland County Department of Planning and Development
(if applicable).
(6)
One copy to the Westmoreland County Department of Public Safety/local
emergency management coordinator (when applicable).
(7)
One copy to DEP (when applicable).
B.
Notification of affected municipalities. The Township shall notify
municipalities upstream and downstream of the development site which
may be affected by the stormwater runoff and proposed controls for
the site. Copies of the plans will be made available to the affected
municipalities upon request. Comments received from any affected municipalities
will be considered by the Township Engineer and County agencies in
their reviews.
C.
Review by the Township Engineer and Westmoreland Conservation District
(WCD). Stormwater management plans shall be reviewed by the Township
Engineer and WCD. BMPs shall be shown on all stormwater management
plans and erosion and sedimentation control plans, as applicable.
At its discretion, the Township and/or WCD may also engage other specialists
in hydrology or hydraulics to assist with the stormwater management
plan review. The costs of such specialist review shall be borne by
the applicant and shall be paid prior to the issuance of any permits.
The WCD will review the plan for general compliance with the watershed
plan standards and criteria and watershed-wide impacts and, where
appropriate, may consult with adjacent municipalities for their comments.
If the WCD review identifies the improper application of the watershed
standards and criteria or the possibility of harmful impacts downstream
from the development site's proposed stormwater management system,
the applicant and Township Engineer will be notified so that the necessary
modifications can be made to promote safe stormwater management. The
Township and the WCD shall notify the applicant in writing within
45 days whether the SWM site plan is approved or disapproved. If the
SWM site plan involves a subdivision and land development plan, the
notification shall occur within 90 days, unless the applicant is notified
that a longer notification period is provided by other statute regulation
or ordinance. If modifications are required, the review period may
be extended by the Township and the WCD in order for the applicant
to address inadequacies.
D.
Township Engineer review. The Township Engineer shall approve or
disapprove the stormwater management plan based on the requirements
of the Township Code, the standards and criteria of the watershed
plan, applicable state and federal requirements and good engineering
practice. The Township Engineer shall submit a written report, along
with supporting documentation, stating the reasons for approval or
disapproval.
E.
Status of the engineer's determination. The approval/disapproval
of the site's stormwater management plan by the Township Engineer
shall be submitted to the Unity Township Board of Supervisors for
final action. Final approval of the plan rests with the Township.
F.
Permits required from other governmental agencies. Where the proposed
development requires a permit from the Pennsylvania DEP, PennDOT,
or an erosion/sedimentation permit or Chapter 105 permit from the
Westmoreland Conservation District, or an approval or permit from
any other person or governmental agency, then final stormwater management
plan approval shall be conditioned upon receipt of such permits. However,
no building permit shall be issued, nor construction or development
begin until all requisite permits are received and copies filed with
the Township.
H.
A disapproved stormwater management plan may be resubmitted, with
the revisions addressing the Township's and WCD's concerns,
to the Township and the WCD in accordance with this chapter.
A.
Upon final stormwater management plan approval and receipt of all
necessary permits, financial guarantees and agreements, the applicant
may commence to install or implement the approved stormwater management
plan, BMPs plan or erosion and sedimentation plan controls.
B.
Prior to the start of construction, the applicant shall schedule
and conduct a pre-construction meeting that includes the owner or
owner's representative, the design professional for the project,
the contractor and any subcontractors, utility representatives, municipal
code officer, Building Inspector, Township Engineer, WCD inspector
and any other personnel deemed relevant to review and discuss the
site plan, E&S controls and the stormwater management facilities.
The meeting should address critical stages of construction that will
require inspections by a certified professional and other documentation
that will be needed in order for an as-built drawing to be prepared
and approved by the Township and the WCD.
C.
If site development or building construction does not begin within
two years of the date of final approval of the stormwater management
plan, then before doing so, the applicant shall re-submit the stormwater
management plan, BMPs plan or erosion or sedimentation plan to verify
that no condition has changed on the property, adjacent to the site
or within the watershed that would affect the feasibility or effectiveness
of the previously approved stormwater management controls. Further,
if for any reason development activities are suspended for two years
or more, then the same requirement for re-submission of the stormwater
management plan shall apply. There shall be no vested interest in
stormwater management plans where work does not commence within two
years or if development activities are suspended for two years and
less than 25% of the development activities are completed, and in
such case, upon resubmission the applicant shall comply with the stormwater
standards in effect at the time of resubmission.
A.
If the request for a plan modification is initiated before construction
begins, the stormwater management plan must be resubmitted and reviewed
according to the procedures, contained in this chapter, effective
the time of resubmission.
B.
If the request for a plan modification is initiated after construction
is underway, the Township Engineer and the WCD shall have the authority
to approve or disapprove the modification based on field conditions,
provided:
(1)
The requested changes in stormwater controls do not result in any
modifications to other approved Township land use/development requirements
(e.g., building setbacks, yards, etc.); and
(2)
The performance standards in this chapter are met. Notification of
the Engineer's and WCD's action shall be sent to the Unity
Township Supervisors, which may issue a stay of the plan modification
and require the permittee to re-submit the plan modification for full
stormwater management plan review in accordance with this chapter.
C.
It shall be unlawful and a violation of this chapter for any person
to alter, replace, modify, landscape or remove, or otherwise adversely
affect, any permanent stormwater management facilities, BMP controls,
or any area within a stormwater easement, or any area dedicated or
designated for stormwater facilities and/or BMPs required by an approved
stormwater management plan or a BMP operations and maintenance plan,
or to allow the property to remain in a condition which does not conform
to an approved stormwater management plan or BMP operations and maintenance
plan, unless an exception is granted, in writing, by the Township
and/or approval is secured from all relevant agencies of the commonwealth.
A.
The Township Engineer or a designated representative shall inspect
the implementation, construction, condition, operation and maintenance
of the temporary and permanent stormwater management system and controls
for the development site. The Township or a designated representative
shall have the right to temporarily locate and/or install on any BMP
such devices as it deems necessary to conduct monitoring and/or sampling
of the discharge from such BMP.
B.
The permittee shall notify the Township Engineer and the WCD not
less than 48 hours in advance of the completion of the following development
phases to enable inspections to occur:
(1)
At the completion of preliminary site preparation, including the
stripping of vegetation, stockpiling of topsoil and construction of
temporary stormwater management control facilities.
(2)
At the completion of rough grading, but prior to placing topsoil,
permanent drainage or other site development improvements and ground
covers.
(3)
During construction of the permanent stormwater facilities and BMPs
at such times as specified by the Township Engineer.
(4)
Special structure inspections: when excavations are completed for
retaining and crib walls and when reinforcing steel is in place before
concrete is poured for cast-in-place structures.
(5)
Drainage facility inspection: when drainage facilities are being
installed and before such facilities are backfilled.
(6)
At the time of completion of permanent stormwater management facilities
and BMPs including established ground covers and plantings.
(7)
At the time of completion of final grading, vegetative control measures
or other site restoration work done in accordance with the approved
plan and permit.
C.
The Township and/or WCD may conduct such other inspections during
construction as it deems appropriate.
D.
No work shall commence on any subsequent phase until the preceding
one has been inspected and approved. If there are deficiencies in
any phase, the Township Engineer and/or WCD shall issue a written
description of the required corrections and establish the time period
in which they must be made.
E.
If, during construction, the contractor or permittee identifies any
site condition, such as subsurface soil conditions, alterations in
surface or subsurface drainage, which could affect the feasibility
of the approved stormwater facilities, or erosion and sedimentation
controls he/she shall notify the Township Engineer and WCD within
24 hours of the discovery of such condition and request a field inspection.
The Township Engineer and WCD shall determine if the condition requires
a modification of the stormwater management plan, BMPs plan or erosion
and sedimentation control plan.
F.
In cases where grading is to be performed and/or stormwater facilities
or erosion and sedimentation controls are to be installed in areas
of landslide-prone soils or other special site conditions exist, the
Township may require special precautions such as a geotechnical study,
soil tests and core borings, full-time inspectors and/or similar measures.
All costs of any such measures shall be borne by the permittee.
G.
Safety precautions.
(1)
If, at any stage of work, the Code Official determines that the continuation
of the work, as authorized by the existing permit, is likely to endanger
any property or streets or ways or to create hazardous conditions,
the Code Official may require, reasonable safety precautions be taken
to avoid such hazardous condition.
(2)
Safety precautions may include, but shall not be limited to, specifying
a less flat or exposed slope, the construction of additional drainage
facilities, berms, terracing, compaction, cribbing, or walls.
A.
The developer shall be responsible for providing "as-built" drawings
of all stormwater management facilities and BMPs included in the approved
Stormwater Management Plan within 60 days following the completion
of their construction. "As-built drawings" for subdivision plans must
identify any and all lots that are to have individual on-lot controls
(i.e., dry wells, et al.) and provide a description of the type of
on-lot control, a typical detail of that control and the basis for
their individual design (i.e., storage volume per impervious area),
as identified in the approved Stormwater Management Plan for the subdivision.
The "as-built" drawings shall contain an explanation of any deviations
from the construction plans and how such deviations were approved
by the Township and WCD.
B.
As-built calculations. For developments with detention/retention
basin(s), the developer shall submit calculations bearing the seal
of a registered professional engineer, surveyor, or landscape architect
verifying that the peak discharge rates from the as-built basin(s)
for the post-development design storms will be less than or equal
to their respective allowable discharge rates established in the approved
stormwater management plan. At a minimum, for each constructed basin,
these calculations shall include:
(1)
A stage-storage-discharge rating table for the as-built basin and
its outlet structure(s);
(2)
The post-development runoff hydrograph to the basin for each of the
design storms. The post-development runoff hydrographs to the basin
as provided in the approved stormwater management plan for the development
may be used as long as as-built site conditions closely replicate
those conditions provided in the approved stormwater management plan.
The use of the hydrographs provided in the approved stormwater management
plan is subject to approval by Unity Township or the Township's
representative;
(3)
Post-development runoff hydrograph routed through the basin for each
of the design storms using the Modified-Puls method or a recognized
reservoir routing method subject to the approval of Unity Township
or the Township's representative. The stage-storage-discharge
rating table for the as-built basin shall be used to route the runoff
hydrographs through the basin.
C.
The "as-built" drawing submission shall include a certification of
completion signed by a qualified professional verifying that all permanent
stormwater management facilities and BMPs have been constructed according
to the approved plans and specifications or any modification of same
approved by the Township. The latitude and longitude coordinates for
all permanent stormwater management facilities and BMPs must also
be submitted, at the central location of the BMPs. If any licensed
qualified professionals contributed to the construction plans, then
a licensed qualified professional must sign the completion certificate.
D.
After receipt of the completion certification by the Township, the
Township and WCD shall conduct a final inspection of the facilities.
E.
An occupancy permit shall not be issued until the certification of
completion has been secured, a stormwater management operations and
maintenance agreement has been entered and an appropriate stormwater
facilities bond is in place. The occupancy permit shall be required
for each lot owner and/or developer for all subdivisions and land
developments in the Township.
