A.
For all regulated activities, unless specifically exempted in § 310-12 of this chapter:
(1)
Preparation and implementation of an approved SWM site plan is required.
(2)
No regulated activities shall commence until the Borough issues written
approval of a SWM site plan which demonstrates compliance with the
requirements of this chapter.
(4)
The SWM site plan approved by the Borough, shall be on-site throughout
the duration of the regulated activities.
B.
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 (including,
but not limited to, Chapter 102, Erosion and Sediment Control) 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), No. 363-2134-008 (April 15, 2000), as amended and updated.
[1]
Editor's Note: See 35 P.S. § 691.1 et seq.
C.
For all regulated activities, stormwater BMPs shall be designed,
installed, implemented, operated, and maintained 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,[2] conform to the state water quality requirements, meet
all requirements under the Stormwater Management Act[3] and any more stringent requirements as determined by the
Borough.
D.
The Borough may, after consultation with PADEP and/or LCCD, 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.
E.
All regulated activities shall include, to the maximum extent practicable,
measures 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, natural slopes,
existing native vegetation and woodlands.
(b)
Create, maintain, or extend riparian buffers and protect existing
forested buffers.
(c)
Provide trees and woodlands adjacent to impervious areas whenever
feasible.
(d)
Minimize the creation of impervious surfaces and the degradation
of waters of the commonwealth and promote groundwater recharge.
(e)
Protect natural systems and processes (drainageways, vegetation,
soils, and sensitive areas) and maintain, as much as possible, the
natural hydrologic regime.
(f)
Incorporate natural site elements (wetlands, stream corridors,
mature forests) as design elements.
(g)
Avoid erosive flow conditions in natural flow pathways.
(h)
Minimize soil disturbance and soil compaction.
(i)
Minimize thermal impacts to waters of the commonwealth.
(j)
Disconnect impervious surfaces by directing runoff to pervious
areas wherever possible, and decentralize and manage stormwater at
its source.
(3)
Applicants are encouraged to incorporate the techniques for low-impact
development practices described in the "Pennsylvania Stormwater Best
Management Practices Manual (BMP Manual)" to reduce the costs of complying
with the requirements of this chapter and the state water quality
requirements.
(4)
If methods other than green infrastructure and low impact development
(LID) methods are proposed to achieve the volume and rate controls
required under this chapter, the SWM site plan must include a detailed
justification demonstrating that the use of LID and green infrastructure
is not practicable.
[Added 9-13-2022 by Ord.
No. 819]
F.
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 developed parcel, the
new impervious area is subject to the requirements of this chapter;
and any existing impervious area that is within the new proposed limit
of disturbance is also subject to the requirements of this chapter.
G.
If diffused flow 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
harm will result from the concentrated discharge.
(1)
Applicant must provide an executed easement for newly concentrated
flow across adjacent properties.
H.
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 chapter.
I.
Where watercourses traverse a development site, drainage easements
(with a minimum width of 20 feet) shall be provided conforming to
the line of such watercourses. The terms of the easement shall prohibit
excavation, the placing of fill or structures, and any alterations
that may adversely affect the flow of stormwater within any portion
of the easement. Also, maintenance, including mowing of vegetation
within the easement may be required, except as approved by the appropriate
governing authority.
J.
When it can be shown that, due to topographic conditions, natural
drainageways on the site cannot adequately provide for drainage, open
channels may be constructed conforming substantially to the line and
grade of such natural drainageways. Work within natural drainageways
shall be subject to approval by PADEP under regulations at 25 Pa.
Code Chapter 105 through the joint permit application process, or,
where deemed appropriate by PADEP, through the general permit process.
K.
Any stormwater management facilities or any facilities that constitute
water obstructions (e.g., culverts, bridges, outfalls, or stream enclosures,
etc.) that are regulated by this chapter, that will be located in
or adjacent to waters of the commonwealth (including wetlands), shall
be subject to approval by PADEP under regulations at 25 Pa. Code Chapter
105 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.
L.
Should any stormwater management facility require a dam safety permit
under PADEP Chapter 105, the facility shall be designed in accordance
with Chapter 105 and meet the regulations of Chapter 105 concerning
dam safety which may be required to pass storms larger than one-hundred-year
event.
M.
Any stormwater management facilities regulated by this chapter that
will be located on, or discharged onto state highway rights-of-way
shall be subject to approval by the Pennsylvania Department of Transportation
(PennDOT).
N.
When stormwater management facilities are proposed within 1,000 feet
of a downstream municipality, the stormwater analysis shall be submitted
to the downstream municipality's engineer for review and comment.
O.
Unless an alternate design is submitted to the Borough for review,
and said design is prepared by a licensed (in the Commonwealth of
Pennsylvania) geologist or geotechnical engineer:
(1)
No stormwater facilities shall be placed in, over or immediately
adjacent to the following features:
(2)
The minimum isolation distance from stormwater management basins
to the listed geologic features shall be as follows:
(3)
Stormwater runoff from any subdivision or land development activities
shall not be discharged into sinkholes unless otherwise shown.
P.
The design of facilities over karst shall include an evaluation and
implementation of measures to minimize adverse effects.
Q.
Roof drains shall not be connected to sanitary or storm sewers. When
it is more advantageous to connect directly to streets or storm sewers,
then the Borough shall permit it on a case-by-case basis.
R.
Infiltration BMPs shall be spread out, 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.
[Added 9-13-2022 by Ord.
No. 819]
S.
Normally dry, open-top, storage facilities shall 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.
[Added 9-13-2022 by Ord.
No. 819]
T.
The design storm volumes to be used in the analysis of peak rates
of discharge shall be 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 145 can be accessed
at: http://hdsc.nws.noaa.gov/hdsc/pfds/.
[Added 9-13-2022 by Ord.
No. 819]
U.
For all regulated activities, SWM BMPs shall be designed, implemented,
operated, and maintained to meet the purposes and requirements of
this chapter and to meet all requirements under Title 25 of the Pennsylvania
Code, the Clean Streams Law, and the Storm Water Management Act.
[Added 9-13-2022 by Ord.
No. 819]
B.
The applicant must demonstrate that the following BMPs are being
utilized to the maximum extent practicable to receive consideration
for the exemptions:
(1)
Design around and limit disturbance of floodplains, wetlands, and
natural slopes over 15%, existing native vegetation, and other sensitive
and special value features.
(2)
Maintain riparian and forested buffers.
(3)
Limit grading and maintain nonerosive flow conditions in natural
flow paths.
(4)
Maintain existing tree canopies near impervious areas.
(5)
Minimize soil disturbance and reclaim disturbed areas with topsoil
and vegetation.
(6)
Direct runoff to pervious areas.
C.
The applicant must demonstrate that the proposed development/additional
impervious area will not adversely impact the following:
D.
An applicant proposing regulated activities, after demonstrating compliance with Subsections A, B, and C, may be exempted from various requirements of this chapter according to the following table:
|
New Impervious Area*
[Since the Date of Adoption of this chapter]
(square footage)
|
Applicant Must Submit to the Borough
|
|---|---|
|
0 to 500
|
—
|
|
500 to 5,000
|
Volume controls and SWM site plan and report
|
|
> 5,000
|
Rate controls, volume controls, SWM site plan and report and
record drawings
|
|
NOTES:
| |
|---|---|
|
*
|
Gravel in the existing condition shall be considered pervious
and proposed gravel shall be considered impervious.
|
E.
The purpose of this section is to ensure consistency of stormwater
management planning between local ordinances and NPDES permitting
(when required) and to ensure that the applicant has a single and
clear set of stormwater management standards to which the applicant
is subject. The Borough may accept alternative stormwater management
controls provided that:
(1)
The applicant, in consultation with the Borough, PADEP and/or LCCD,
states that meeting the requirements of the volume controls or rate
controls of this chapter is not possible or creates an undue hardship.
(2)
The alternative stormwater management controls, proposed by the applicant,
are documented to be acceptable to the Borough, PADEP and/or LCCD
for NPDES requirements pertaining to post construction stormwater
management requirements.
F.
Forest management and timber operations are exempt from rate and
volume control requirements and SWM site plan preparation requirement
of this chapter provided the activities are performed according to
the requirements of 25 Pa. Code Chapter 102. It should be noted that
temporary roadways are not exempt.
G.
Agricultural activities are exempt from the requirements of this
chapter, provided the activities are performed according to the requirements
of 25 Pa. Code Chapter 102.
H.
Linear roadway improvement projects that create additional impervious
area are not exempt from the requirements of this chapter. However,
alternative stormwater management strategies may be applied at the
joint approval of the Borough and the LCCD (if an NPDES permit is
required) when site limitations (such as limited right-of-way) and
constraints (as shown and provided by the applicant) preclude the
ability of the applicant to meet the enforcement of the stormwater
management standards in this chapter. All strategies must be consistent
with PADEP's regulations, including NPDES requirements.
I.
The Borough may, after an applicant has demonstrated compliance with Subsections A, B, and C, grant a modification of the requirements of one or more provisions of this chapter if the literal enforcement will exact undue hardship because of peculiar conditions pertaining to the land in question, provided that such modification will not be contrary to the public interest and that the purpose and intent of this chapter is observed.
(1)
All requests for a modification shall be in writing and shall state
in full the grounds and facts of unreasonableness or hardship on which
the request is based, the provision or provisions of this chapter
involved, and the minimum modification necessary.
J.
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.
[Added 9-13-2022 by Ord.
No. 819]
A.
Based on the moratorium area assessment, infiltration is prohibited
in the Borough. In those cases where the applicant chooses to pursue
infiltration, the applicant shall provide a detailed geologic evaluation,
consisting of karst hazard assessment and a remediation plan. This
evaluation shall be prepared and signed/sealed by either a qualified,
Pennsylvania licensed geotechnical engineer or geologist with experience
in karst geology assessment and sinkhole remediation. At a minimum,
this evaluation must include the following:
(1)
Review of historical photos for karst features.
(2)
A
fracture trace analysis using available aerial photographs.
(3)
Documentation of a site field view to field verify observed and suspect
karst solution features.
(4)
An appropriate geophysical survey of suspect areas (with emphasis
on those areas of proposed construction and within 10 feet of those
areas), delineated by photo and field reviews, using micro-gravity
surveys, ground-penetrating radar, or an alternate technology of equal
or better capability.
(5)
Backhoe probes of suspect features.
(6)
A plot of all observed and suspect karst features on the base mapping
of the site prepared for the development plan, at a scale of one inch
equals 50 feet, with a larger scale plot of complex features at a
scale of one inch equals 20 feet.
(7)
A specific commentary on the suitability of the karst portions of
the site to be developed as proposed.
(8)
A report presenting findings, conclusions, and recommendations of
the investigation. The report must include specifications for sinkhole
mitigation during construction, and methods to reduce sinkhole development
during construction.
(9)
Any recommendations involving construction techniques must be incorporated
into the development construction drawing notes and details.
B.
The green infrastructure and low impact development practices provided in the BMP Manual shall be utilized for all regulated activities wherever possible. Dependent upon the geologic evaluation described in § 310-13A, water volume controls shall be implemented using the Design Storm Method in §310-13B(1) or the Simplified Method in § 310-13B(2) below. For regulated activity areas equal or less than one acre that do not require hydrologic routing to design the stormwater facilities, this chapter establishes no preference for either methodology; therefore, the applicant may select either methodology on the basis of economic considerations, the intrinsic limitations on applicability of the analytical procedures associated with each methodology, and other factors.
[Amended 9-13-2022 by Ord. No. 819]
(1)
The Design Storm Method (CG-1 in the BMP Manual Chapter 4) is applicable to any size of regulated activity. This method requires detailed modeling based on site conditions.
(a)
Do not increase the post-development total runoff volume for
all storms equal to or less than the two-year, twenty-four-hour duration
precipitation.
(2)
The Simplified Method (CG-2 in the BMP Manual Chapter 4) 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:
(a)
Stormwater facilities shall capture at least the first two inches
of runoff from all new impervious surfaces.
(b)
At least the first one inch of runoff from new 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.
(c)
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.
D.
Actual field infiltration tests at the location of the proposed elevation of the stormwater infiltration BMPs are required to support the design outlined in Subsection B. Infiltration tests and an evaluation of soil limiting zones shall be conducted in accordance with BMP Manual. The Borough shall be notified 24 hours prior to infiltration tests being conducted as to provide an opportunity for the Borough to witness the tests.
[Amended 9-13-2022 by Ord. No. 819]
The calculated peak rates of runoff for stormwater originating
on the project site must meet the following conditions:
A.
Post-development discharge rates shall not exceed the predevelopment
discharge rates for the one-, two-, five-, ten-, twenty-five-, fifty-,
and 100-year, twenty-four-hour storm events. If it is shown that the
peak rates of discharge indicated by the post-development 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 100-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.
[Added 9-13-2022 by Ord.
No. 819]
A.
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.
C.
Minimum management requirements for riparian buffers.
(1)
Existing native vegetation shall be protected and maintained
within the riparian buffer easement.
(2)
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 Borough and shall be recorded in the Lebanon 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 as required by Chapter 380, Zoning, unless otherwise specified in Chapter 380, Zoning.
E.
Any permitted use within the riparian buffer easement shall be conducted
in a manner that will maintain the extent of the existing 100-year
floodplain, improve or maintain the stream stability, and preserve
and protect the ecological function of the floodplain.
G.
Septic drainfields 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.
