A.
For all regulated activities, unless preparation of an SWM site plan is specifically exempted in § 224-12:
B.
SWM site plans approved by the municipality, in accordance with § 224-21, shall be on site throughout the duration of the regulated activity.
C.
These standards apply to the landowner, authorized agent, and/or
any person engaged in regulated activities.
D.
For all regulated earth disturbance activities, erosion and sediment
control BMPs shall be designed, implemented, operated, and maintained
during the regulated earth disturbance activities (e.g., during construction)
to meet the purposes and requirements of this chapter and to meet
all requirements under Title 25 of the Pennsylvania Code and the Clean
Streams Law.[1] Various BMPs and their design standards are listed in
the Erosion and Sediment Pollution Control Program Manual (E&S
Manual[2]), No. 363-2134-008, as amended and updated.
E.
Impervious areas.
(1)
The measurement of impervious areas shall include all of the impervious
areas in the total proposed development even if development is to
take place in stages.
(2)
For development taking place in stages, the entire development plan
must be used in determining conformance with this chapter.
(3)
For projects that add impervious area to a parcel, the total impervious area on the parcel is subject to the requirements of this chapter; except that the volume controls in § 224-13 and the peak rate controls of § 224-14 do not need to be retrofitted to existing impervious areas that are not being altered by the proposed regulated activity.
(4)
Gravel surfaces in the existing (predevelopment) condition are to
be considered pervious where permitted.
(5)
Gravel surfaces in the proposed (postdevelopment) condition are to
be considered impervious where permitted.
F.
Stormwater flows onto adjacent or downstream property shall not be
created, increased, decreased, relocated, impeded, or otherwise altered
without written notification of the affected property owner(s). Notification
shall include a description of the proposed development and the stormwater
flows that are being created, increased, decreased, relocated, impeded,
or otherwise altered. Adjacent property shall at a minimum include
any property having a shared boundary with the subject property of
the SWM site plan; however, if in the judgement of the designated
plan reviewer additional properties are being affected, additional
notifications may be required. Proof of notification (signed postal
receipt, for example) shall be included as part of the SWM plan submission
to the municipality. Such stormwater flows shall be subject to the
requirements of this chapter.
G.
All regulated activities shall include such measures as necessary
to:
(1)
Protect health, safety, and property.
(2)
Meet the water quality goals of this chapter by implementing measures
to:
(a)
Minimize disturbance to floodplains, wetlands, and wooded areas.
(b)
Maintain or extend riparian buffers.
(c)
Avoid erosive flow conditions in natural flow pathways.
(d)
Minimize thermal impacts to waters of this Commonwealth.
(e)
Disconnect impervious surfaces by directing runoff to pervious
areas, wherever possible.
(f)
Guarantee and reduce infiltration of stormwater into our sanitary
sewer by means of construction, installation, maintenance and repair
of all stormwater facilities existing or newly constructed.
(3)
Incorporate methods described in the Pennsylvania Stormwater Best
Management Practices Manual (BMP Manual[3]). If methods other than green infrastructure and LID methods
are proposed to achieve the volume and rate controls required under
this chapter, the SWM site plan must include a detailed justification,
acceptable to the designated plan reviewer, demonstrating that the
use of LID and green infrastructure is not practicable.
[3]
Reference: Pennsylvania Department of Environmental Protection.
No. 363-0300-002 (December 2006), as amended and updated. Pennsylvania
Stormwater Best Management Practices Manual. Harrisburg, PA.
H.
Infiltration BMPs should be dispersed throughout the project site
at strategic locations, made as shallow as practicable, and located
to maximize use of natural on-site infiltration features while still
meeting the other requirements of this chapter.
I.
Normally dry, open-top storage facilities should completely drain
both the volume control and rate control capacities over a period
of time not less than 24 and not more than 72 hours from the end of
the design storm.
J.
The design storm precipitation depths to be used in the analysis
of peak rates of discharge shall be as obtained in PennDOT's
Drainage Manual, Publication 584, Appendix 7A; or obtained from the
latest version of the Precipitation-Frequency Atlas of the United
States, National Oceanic and Atmospheric Administration (NOAA), National
Weather Service, Hydrometeorological Design Studies Center, Silver
Spring, Maryland. NOAA's Atlas 14[4] can be accessed at: http://hdsc.nws.noaa.gov/hdsc/pfds/.
[4]
Reference: U.S. Department of Commerce, National Oceanic and
Atmospheric Administration, National Weather Service, Hydrometeorological
Design Studies Center. 2004-2006. Precipitation-Frequency Atlas of
the United States, Atlas 14, Volume 2, Version 3.0, Silver Spring,
Maryland. Internet address: http://hdsc.nws.noaa.gov/hdsc/pfds/.
K.
M.
The municipality may, after consultation with DEP, approve measures
for meeting the state water quality requirements other than those
in this chapter, provided that they meet the minimum requirements
of, and do not conflict with, state law, including but not limited
to the Clean Streams Law.
Some activities may be exempted from the full requirements of
this chapter as detailed below. Unless specifically noted as automatic,
exemption requests must be submitted to and approved by the Borough.
Any exemption granted shall apply only to the portions of this chapter
specifically noted. All other stormwater management design elements,
such as a storm sewer system, culverts, erosion and sedimentation
controls, etc., shall still be required.
A.
There shall be no exemptions for activities resulting in earth disturbance
exceeding one acre.
B.
Activities that do not require a site plan or land development plan
approval from the Borough may be exempt, subject to the review of
the exemption request by the Borough.
C.
Individual detached single-family homes that are not part of an existing
or planned subdivision with an approved SWM site plan shall be exempt
from the requirement to submit a complete SWM site plan.
D.
The subdivision of one single-family detached residential lot into
two such lots, or a subdivision including only the revision of the
lot line(s) between two such lots, shall be exempt from the requirement
to submit a complete SWM site plan. Should the Borough suspect that
repeated such subdivisions are being used to circumvent the planning
requirement, the Borough reserves the right to revoke the exemption.
E.
The work required to return a property to its previous condition
following a loss resulting from an act of nature, fire, or accident,
etc., shall be exempt from the requirement to submit a complete SWM
site plan.
F.
Emergency maintenance work performed for the protection of public
health, safety, and welfare may be exempted from the requirements
in this chapter to obtain approval for an SWM site plan prior to the
commencement of the activity. A written description of the scope and
extent of such work shall be submitted to the Borough within two calendar
days of the commencement of the activity. If the Borough deems that
the work does not constitute an emergency, then the work shall cease
immediately and not resume until an SWM site plan is submitted to
and approved by the Borough. The purpose of this exemption is to allow
emergency work to proceed immediately only. All work must otherwise
comply with all applicable provisions of this chapter.
G.
Maintenance work performed on an existing stormwater management facility
that was installed in accordance with plans and specifications approved
by the Borough may be exempted from the requirements of this chapter.
The facility owner shall notify the Borough a minimum of three working
days in advance, with such notice to include a description of the
work to be performed. All work should be completed in accordance with
the approved operation and maintenance plan for the facility and shall
only be performed to bring the facility back into conformance with
the original approved plan. Any work that would alter the configuration,
capacities, or operation of the facility must be submitted to the
Borough for approval.
H.
Activities related solely to property maintenance, such as resurfacing
an existing parking lot, replacement of existing sidewalks, roof replacement,
building exterior repairs, etc., shall be automatically exempt from
the requirements of this chapter if no additional impervious area
is added as a result of the activities.
I.
The use of land for home gardening for home consumption shall be
automatically exempt from the requirements of this chapter.
J.
Agricultural activity is exempt from the SWM site plan preparation
requirements of this chapter, provided the activities are performed
according to the requirements of 25 Pa. Code Chapter 102.
K.
Forest management and timber operations are exempt from the SWM site
plan preparation requirements of this chapter, provided the activities
are performed according to the requirements of 25 Pa. Code Chapter
102.
M.
The following activities may be exempt from the requirements to submit
a complete SWM site plan. In all cases, however, appropriate stormwater
quality BMPs must be implemented on the site where required. Exemptions
will not be granted if the activity is found to contribute pollution
to the waters of the Commonwealth, or if the runoff from the activity
impacts an adjacent property.
(1)
Minor impact activities.
(a)
This shall apply to an activity not classified as a single-family
detached home on a single lot.
(b)
An activity shall be classified as a "minor impact" if it involves
less than 1,200 square feet (< 1,200 square feet) of impervious
area, to include both newly created impervious area and any reconfiguration
of existing impervious area, and results in a total earth disturbance
of less than 5,000 square feet (< 5,000 square feet).
(c)
This exemption can only be applied once for each parcel. Subsequent,
or phased, regulated activities on the same or contiguous properties
which result in an overall total of 1,200 square feet or greater (> 1,200 square feet) of impervious surface, or 5,000
square feet or greater (equal or greater than 5,000 square feet) of
earth disturbance shall be subject to the full requirements of this
chapter.
(d)
The area of any existing impervious surfaces that may be permanently
replaced with pervious surfaces on a project site may NOT be deducted
from the area of impervious surface created/reconfigured to qualify
for this exemption.
(e)
The applicant shall submit a narrative describing the project,
documentation of the total proposed impervious area and disturbed
area, proposed use of any BMPs on the site, including any calculations
or justification for their selection, as well as the operation and
maintenance plan and agreement for the facilities.
(2)
Vertical extensions.
(a)
This shall apply to an activity not classified as a single-family
detached home on a single lot.
(b)
Such activities must involve only the vertical extension of
a structure or portions thereof, with an addition of the same size
and shape as the structure or portion thereof directly beneath the
addition, and which require no earth disturbance activities other
for the construction of said addition. Appropriate erosion and sedimentation
control measures must be employed during any construction activities.
(3)
Small projects. Regulated activities involving between 1,200 square feet and 5,000 square feet of new or reconfigured impervious area and less than one acre of earth disturbance shall be considered a "small project" and must submit an SWM site plan to the Borough which shall consist of the following items and related supportive material needed to determine compliance with §§ 224-13 through 224-15. The applicant can use the protocols in the Small Project stormwater management site plan included in Appendix C.[1]
(a)
General description of proposed stormwater management techniques,
including construction specifications of the materials to be used
for stormwater management facilities.
(b)
An erosion and sediment control plan, including all reviews
and letters of adequacy from the Conservation District where appropriate.
(c)
Limits of earth disturbance, including the type and amount of
impervious area that is proposed; proposed structures, roads, paved
areas, and buildings; and a statement, signed by the applicant, acknowledging
that any revision to the approved drainage plan must be approved by
the municipality, and that a revised erosion and sediment control
plan must be submitted to the municipality or Conservation District
for approval.
(d)
All stormwater management facilities must be located on a plan
and described in detail; and all calculations, assumptions, and criteria
used in the design of the stormwater management facilities must be
shown.
[1]
Editor's Note: Appendix C is included at the end of this chapter.
N.
Roadway resurfacing and maintenance projects, which do not increase
impervious area, and underground infrastructure projects are exempt
from the provisions of this chapter, provided the activities meet
the requirements of all other municipal, state and federal requirements.
O.
The Borough may deny or revoke any exemption pursuant to this section
at any time for any project that the Borough believes may pose a threat
to public health and safety or the environment.
P.
Voluntary green stormwater infrastructure (GSI) retrofit projects
that are solely intended to better manage runoff from existing development
and are not part of new development or redevelopment are exempt from
the stormwater management provisions of this chapter. This does not
exempt such projects from any other municipal, state, or federal regulation.
The green infrastructure and low-impact development practices
provided in the BMP Manual[1] shall be utilized for all regulated activities wherever
possible. Water volume controls shall be implemented using the Design
Storm Method in Subsection A or the Simplified Method in Subsection
B below. Water volume controls shall be implemented using the Design
Storm Method in Subsection A or the Simplified Method in Subsection
B below, or alternative design criteria as allowed by 25 Pa. Code
Chapter 102.
A.
The Design Storm Method (CG-1 in the BMP Manual[2]) is applicable as a method to any size of regulated activity.
This method requires detailed modeling based on site conditions. The
following shall be incorporated into the CG-1 method:
(1)
Do not increase the postdevelopment total runoff volume for all storms
equal to or less than the two-year, twenty-four-hour duration precipitation.
(2)
At least the first one inch of runoff from the net increase in impervious
surfaces shall be permanently removed from the runoff flow, i.e.,
it shall not be released into the surface waters of this Commonwealth.
Removal options include reuse, evaporation, transpiration, and infiltration.
If the developer provides justification that the listed removal options
are not feasible, and the designated plan reviewer agrees, runoff
shall be detained in a facility designed for a twenty-four to seventy-two-hour
dewatering time in an area with a dedicated stormwater system (not
contributory to a combined sewer system) and shall be detained in
a facility designed for a seventy-two-hour dewatering time in an area
contributory to a combined sewer system before discharge to local
stormwater systems or the environment.
[2]
Reference: Pennsylvania Department of Environmental Protection.
No. 363-0300-002 (December 2006), as amended and updated. Pennsylvania
Stormwater Best Management Practices Manual. Harrisburg, PA.
B.
The Simplified Method (CG-2 in the BMP Manual[3]) provided below is independent of site conditions and
should be used if the Design Storm Method is not followed. This method
is not applicable to regulated activities greater than one acre or
for projects that require design of stormwater storage facilities.
For new impervious surfaces:
(1)
Stormwater facilities shall capture at least the first two inches
of runoff from the net increase in impervious surfaces.
(2)
At least the first one inch of runoff from the net increase in impervious
surfaces shall be permanently removed from the runoff flow, i.e.,
it shall not be released into the surface waters of this Commonwealth.
Removal options include reuse, evaporation, transpiration, and infiltration.
If the developer provides justification that the listed removal options
are not feasible, and the designated plan reviewer agrees, runoff
shall be detained in a facility designed for a twenty-four-hour dewatering
time in an area with a dedicated stormwater system (not contributory
to a combined sewer system) and shall be detained in a facility designed
for a seventy-two-hour dewatering time in an area contributory to
a combined sewer system before discharge to local stormwater systems
or the environment.
(3)
Wherever possible, infiltration facilities should be designed to
accommodate infiltration of the entire permanently removed runoff;
however, in all cases at least the first 0.5 inch of the permanently
removed runoff should be infiltrated.
[3]
Reference: Pennsylvania Department of Environmental Protection.
No. 363-0300-002 (December 2006), as amended and updated. Pennsylvania
Stormwater Best Management Practices Manual. Harrisburg, PA.
[1]
Reference: Pennsylvania Department of Environmental Protection.
No. 363-0300-002 (December 2006), as amended and updated. Pennsylvania
Stormwater Best Management Practices Manual. Harrisburg, PA.
A.
For areas not covered by a release rate map from an approved Act
167 Stormwater Management Plan: postdevelopment discharge rates shall
not exceed the predevelopment discharge rates for the one-, two-,
five-, ten-, twenty-five-, fifty-, and one-hundred-year, twenty-four-hour
storm events. This is the equivalent to a 100% release rate area when
compared to those rates shown in the maps contained in Appendix A
(New and Existing Release Rate Management Districts).[1] This predevelopment to postdevelopment control is not
to be misconstrued as the same as the "conditional direct discharge"
areas on the release rate maps. If it is shown that the peak rates
of discharge indicated by the postdevelopment analysis are less than
or equal to the peak rates of discharge indicated by the predevelopment
analysis for one-, two-, five-, ten-, twenty-five-, fifty-, and one-hundred-year,
twenty-four-hour storms, then the requirements of this section have
been met. Otherwise, the applicant shall provide additional controls
as necessary to satisfy the peak rate of discharge requirement. Peak
flows should be computed using the methods included in the chapter
titled "Stormwater Calculations and Methodology" of the PADEP Stormwater
Management BMP Manual.
[1]
Editor's Note: Appendix A is included at the end of this chapter.
B.
For areas covered by a release rate map from an approved Act 167
Stormwater Management Plan: for the one-, two-, five-, ten-, twenty-five-,
fifty-, and one-hundred-year, twenty-four-hour storm events, the postdevelopment
peak discharge rates will follow the applicable approved release rate
maps. These maps are contained in Appendix A (New and Existing Release
Rate Management Districts) of this chapter. For any areas not shown
on the release rate maps, the postdevelopment discharge rates shall
not exceed the predevelopment discharge rates for the specified design
events. Peak flows should be computed using the methods included in
Chapter 8 of the PADEP Stormwater Management BMP Manual.
A.
In order to protect and improve water quality, a riparian buffer
easement shall be created and recorded as part of any subdivision
or land development that encompasses a riparian buffer. The intent
of this chapter in establishing a riparian buffer is to protect and
improve stream water quality. The riparian buffer is intended to slow
overland flow to the stream through the presence of native grasses,
trees and shrubs, allowing infiltration/groundwater recharge; causing
deposition of sediment, nutrients, pesticides, and other pollutants
in the buffer rather than in the stream; and reducing erosion by providing
stream bank stabilization. The trees provide shade for streams, keeping
waters cooler and reducing evaporation.
B.
Except as required by 25 Pa.Code Chapter 102, the riparian buffer easement shall be required for all streams (as defined in Article II) with a contributing watershed area of greater than 10 acres. The riparian buffer easement shall be measured to be a minimum of 35 feet from the top of the streambank (on each side).
C.
Minimum management requirements for riparian buffers.
(1)
No use or construction within the riparian buffer shall be permitted that is inconsistent with the intent of the riparian buffer as described in Subsection A.
(2)
Existing native vegetation shall be protected and maintained within
the riparian buffer easement.
(3)
Whenever practicable, invasive vegetation shall be actively removed
and the riparian buffer easement shall be planted with native trees,
shrubs and other vegetation to create a diverse native plant community
appropriate to the intended ecological context of the site.
D.
The riparian buffer easement shall be enforceable by the municipality
and shall be recorded in the appropriate County Recorder of Deeds
office, so that it shall run with the land and shall limit the use
of the property located therein. The easement shall allow for the
continued private ownership and shall count toward the minimum lot
area required by zoning, unless otherwise specified in the municipal
zoning ordinance.[1]
E.
Any permitted use within the riparian buffer easement shall be conducted
in a manner that will maintain the extent of the existing one-hundred-year
floodplain, improve or maintain the stream stability, and preserve
and protect the ecological function of the floodplain.
F.
Stormwater drainage pipes shall be permitted within the riparian
buffer easement, but they shall cross the easement in the shortest
practical distance. Other structural stormwater management facilities
are not permitted within the riparian buffer easement.
G.
The following conditions shall apply when public and/or private recreation
trails are permitted by the municipality within riparian buffers:
H.
Septic drain fields and sewage disposal systems shall not be permitted
within the riparian buffer easement and shall comply with setback
requirements established under 25 Pa. Code Chapter 73.
I.
Underground utilities shall be permitted within the riparian buffer
easement; however, work shall be performed to minimize disturbance
area and removal of trees. Restoration within the riparian buffer
easement shall be with native species of trees, grasses, and other
plantings. One tree shall be planted for each tree removed and the
restoration shall be designed by a registered professional with the
requisite experience. Aboveground utilities shall only be permitted
to cross the easement perpendicular to the easement or in the shortest
practical distance. Existing utilities may remain and be maintained
as required.
