[HISTORY: Adopted by the Borough Council
of the Borough of Medford Lakes 3-22-2023 by Ord. No. 693.[1] Amendments noted where applicable.]
[1]
Editor's Note: This ordinance also repealed former Ch. 204,
Stormwater Management, adopted 5-10-2007 by Ord. No. 533, as amended.
A.
Policy statement. Flood control, groundwater recharge, erosion control
and pollutant reduction shall be achieved using stormwater management
measures, including green infrastructure best management practices
(BMPs) and nonstructural stormwater management strategies. Green infrastructure
BMPs and low-impact development should be utilized to meet the goal
of maintaining natural hydrology to reduce stormwater runoff volume,
reduce erosion, encourage infiltration and groundwater recharge, and
reduce pollution. Green infrastructure BMPs and low-impact development
should be developed based upon physical site conditions and the origin,
nature and the anticipated quantity, or amount, of potential pollutants.
Multiple stormwater management BMPs may be necessary to achieve the
established performance standards for water quality, quantity, and
groundwater recharge contained in this chapter.
B.
Purpose. The purpose of this chapter is to establish, within the
Pinelands Area portion of Medford Lakes Borough, minimum stormwater
management requirements and controls as authorized by the Pinelands
Protection Act (N.J.S.A. 13:18A-1 et seq.) and consistent with the
Pinelands Comprehensive Management Plan (CMP) (N.J.A.C. 7:50-1.1 et
seq.) and the New Jersey Department of Environmental Protection (NJDEP)
Stormwater Management Regulations (N.J.A.C. 7:8-1.1 et seq.). The
standards in this chapter are intended to minimize the adverse impact
of stormwater runoff on water quality and water quantity, to facilitate
groundwater recharge, and to control and minimize soil erosion, stream
channel erosion, sedimentation and pollution associated with stormwater
runoff. Moreover, Pinelands Area resources are to be protected in
accordance with the antidegradation policies contained in the New
Jersey Surface Water Quality Standards (N.J.A.C. 7:9B-1.1 et seq.).
Additionally, this chapter is intended to ensure the adequacy of existing
and proposed culverts and bridges and to protect public safety through
the proper design and operation of stormwater BMPs. If there are any
conflicts between a provision required by the Pinelands CMP and a
provision required by the NJDEP, the Pinelands CMP provision shall
apply.
C.
Applicability.
(1)
The terms "development," "major development" and "minor development" are defined in § 204-2 in accordance with the Pinelands CMP (N.J.A.C. 7:50-2.11) and differ from the definitions of "development" and "major development" contained in the NJDEP Stormwater Management Regulations (N.J.A.C. 7:8-1.2).
(2)
This chapter shall apply within the Pinelands Area to all major development,
and to minor development meeting the following criteria:
(a)
Development involving the construction of four or fewer dwelling
units;
(b)
Development involving any nonresidential use and resulting in
an increase of greater than 1,000 square feet of regulated motor vehicle
surfaces; and
(c)
Development involving the grading, clearing, or disturbance
of an area in excess of 5,000 square feet within any five-year period.
For development meeting this criterion, the stormwater management
standards for major development set forth in this chapter shall apply.
D.
Compatibility with other permit and ordinance requirements.
(1)
Development approvals issued pursuant to this chapter are to be considered
an integral part of development approvals and do not relieve the applicant
of the responsibility to secure required permits or approvals for
activities regulated by any other applicable code, rule, act, or ordinance.
In their interpretation and application, the provisions of this chapter
shall be held to be the minimum requirements for the promotion of
the public health, safety, and general welfare.
(2)
This chapter is not intended to interfere with, abrogate, or annual
any other ordinances, rule or regulation, statute, or other provision
of law except that, where any provision of this chapter imposes restrictions
different from those imposed by any other ordinance, rule or regulation,
or other provision of law, the more restrictive provisions or higher
standards shall control.
(3)
In the event that a regional stormwater management plan(s) is prepared
and formally adopted pursuant to N.J.A.C. 7:8-1.1 et seq. for any
drainage area(s) or watershed(s) of which Medford Lakes Borough is
a part, the stormwater provisions of such a plan(s) shall be adopted
by Medford Lakes Borough within one year of the adoption of a regional
stormwater management plan (RSWMP) as an amendment to an area wide
water quality management plan. Local ordinances proposed to implement
the RSWMP shall be submitted to the Pinelands Commission for certification
within six months of the adoption of the RSWMP per N.J.A.C. 7:8 and
the Pinelands CMP.
For the purpose of this chapter, the following terms, phrases,
words and their derivations shall have the meanings stated herein
unless their use in the text of this chapter clearly demonstrates
a different meaning. When not inconsistent with the context, words
used in the present tense include the future, words used in the plural
number include the singular number, and words used in the singular
number include the plural number. The word "shall" is always mandatory
and not merely directory. The definitions below are the same as or
based on the corresponding definitions in the NJDEP Stormwater Management
Rules at N.J.A.C. 7:8-1.2 unless otherwise defined in the Pinelands
CMP at N.J.A.C. 7:50-2.11, in which case the definition corresponds
to the CMP definition.
The increase in soil bulk density.
The area from which stormwater runoff drains to a stormwater
management measure, not including the area of the stormwater management
measure itself.
An agency designated by the County Commissioners to review
municipal stormwater management plans and implementing ordinance(s).
The county review agency may either be:
A person professionally qualified and duly licensed in New
Jersey to perform engineering services that may include, but not necessarily
be limited to, development of project requirements, creation and development
of project design and preparation of drawings and specifications.
The change of or enlargement of any use or disturbance of any
land, the performance of any building or mining operation, the division
of land into two or more parcels, and the creation or termination
of rights of access or riparian rights including, but not limited
to:
A change in type of use of a structure or land;
A reconstruction, alteration of the size, or material change
in the external appearance of a structure or land;
A material increase in the intensity of use of land, such as
an increase in the number of businesses, manufacturing establishments,
offices or dwelling units in a structure or on land;
Commencement of resource extraction or drilling or excavation
on a parcel of land;
Demolition of a structure or removal of trees;
Commencement of forestry activities;
Deposit of refuse, solid or liquid waste or fill on a parcel
of land;
In connection with the use of land, the making of any material
change in noise levels, thermal conditions, or emissions of waste
material; and
Alteration, either physically or chemically, of a shore, bank,
or floodplain, seacoast, river, stream, lake, pond, wetlands or artificial
body of water.
In the case of development on agricultural land, i.e., land
use for an agricultural use or purpose as defined at N.J.A.C. 7:50-2.11,
"development" means any activity that requires a state permit, any
activity reviewed by the County Agricultural Board (CAB) and the State
Agricultural Development Committee (SADC), and municipal review of
any activity not exempted by the Right to Farm Act, N.J.S.A. 4:1C-1
et seq.
The placement or reconstruction of impervious surface or
motor vehicle surface, or exposure and/or movement of soil or bedrock
or clearing, cutting, or removing of vegetation. Milling and repaving
is not considered disturbance for the purposes of this definition.
A geographic area within which stormwater runoff, sediments,
or dissolved materials drain to a particular receiving water body
or to a particular point along a receiving water body.
An area or feature which is of significant environmental
value, including but not limited to stream corridors, natural heritage
priority sites, habitats of endangered or threatened species, large
areas of contiguous open space or upland forest, steep slopes, and
wellhead protection and groundwater recharge areas. Habitats of endangered
or threatened species are identified using the NJDEP Landscape Project
as approved by the NJDEP Endangered and Nongame Species Program.
The detachment and movement of soil or rock fragments by
water, wind, ice, or gravity.
A stormwater management measure that manages stormwater close
to its source by:
Areas in industrial and commercial developments where solvents
and/or petroleum products are loaded/unloaded, stored, or applied;
areas where pesticides are loaded/unloaded or stored; areas where
hazardous materials are expected to be present in greater than "reportable
quantities" as defined by the United States Environmental Protection
Agency (EPA) at 40 CFR 302.4; areas where recharge would be inconsistent
with NJDEP approved remedial action work plan or landfill closure
plan and areas with high risks for spills of toxic materials, such
as gas stations and vehicle maintenance facilities.
An area within which water drains to a particular receiving
surface water body, also known as a "subwatershed", which is identified
by a fourteen-digit hydrologic unit boundary designation, delineated
within New Jersey by the United States Geological Survey.
An area within which water drains to a particular receiving
surface water body, also known as a "subwatershed," which is identified
by an eleven-digit hydrologic unit boundary designation, delineated
within New Jersey by the United States Geological Survey.
Small Watershed Hydrology (WINTR-55) Version 1.0, incorporated
herein by reference, as amended and supplemented, available with user
guide and tutorials at http://www.wsi.nrcs.usda.gov/products/W2Q/H&H/Tools_Models/WinTr55.html
or at Natural Resources Conservation Service, 220 Davidson Avenue,
Somerset, NJ 08873. Such surfaces may have varying degrees of permeability.
Is the process by which water seeps into the soil from precipitation.
Any division of land into five or more lots; any construction
or expansion of any housing development of five or more dwelling units;
any construction or expansion of any commercial or industrial use
or structure on a site of more than three acres; or any grading, clearing
or disturbance of an area in excess of 5,000 square feet.
All development other than major development.
Land vehicles propelled other than by muscular power, such
as automobiles, motorcycles, autocycles, and low-speed vehicles. For
the purposes of this definition, "motor vehicle" does not include
farm equipment, snowmobiles, all-terrain vehicles, motorized wheelchairs,
go-carts, gas buggies, golf carts, ski-slope grooming machines, or
vehicles that run only on rails or tracks.
Any pervious or impervious surface that is intended to be
used by motor vehicles and/or aircraft, and is directly exposed to
precipitation, including, but not limited to, driveways, parking areas,
parking garages, roads, racetracks, and runways.
The manual maintained by the NJDEP providing, in part, design specifications, removal rates, calculation methods, and soil testing procedures approved by the NJDEP as being capable of contributing to the achievement of the stormwater management standards specified in this chapter. The BMP Manual is periodically amended by the NJDEP as necessary to provide design specifications on additional best management practices and new information on already included practices reflecting the best available current information regarding the particular practice and the NJDEP's determination as to the ability of that best management practice to contribute to compliance with the standards contained in this chapter. Alternative stormwater management measures, removal rates, or calculation methods may be utilized, subject to any limitations specified in this chapter, provided the design engineer demonstrates to the municipality, in accordance with § 204-3F and N.J.A.C. 7:8-5.2(g), that the proposed measure and its design will contribute to achievement of the design and performance standards established by this chapter.
A chemical element or compound, such as nitrogen or phosphorus,
which is essential to and promotes the development of organisms.
The rate at which water moves through a unit area of soil,
rock, or other material at hydraulic gradient of one.
An individual, corporation, public agency, business trust,
partnership, association, two or more persons having a joint or common
interest, or any other legal entity.
Any dredged spoil, solid waste, incinerator residue, filter
backwash, sewage, garbage, refuse, oil, grease, sewage sludge, munitions,
chemical wastes, biological materials, medical wastes, radioactive
substance [except those regulated under the Atomic Energy Act of 1954,
as amended (42 U.S.C. § 2011 et seq.)], thermal waste, wrecked
or discarded equipment, rock, sand, cellar dirt, industrial, municipal,
agricultural, and construction waste or runoff, or other residue discharged
directly or indirectly to the land, groundwaters or surface waters
of the state, or to a domestic treatment works. "Pollutant" includes
both hazardous and nonhazardous pollutants.
The amount of water from precipitation that infiltrates into
the ground and is not evapotranspired.
Any of the following, alone or in combination:
A net increase in motor vehicle surface; and/or
The total area of motor vehicle surface that is currently receiving
water quality treatment either by vegetation or soil, by an existing
stormwater management measure, or by treatment at a wastewater treatment
plant, where the water quality treatment will be modified or removed.
The level below the natural surface of the ground to which
water seasonally rises in the soil in most years.
Solid material, mineral or organic, that is in suspension,
is being transported, or has been moved from its site of origin by
air, water or gravity as a product of erosion.
The lot or lots upon which development is to occur or has
occurred.
All unconsolidated mineral and organic material of any origin.
Any material(s) or machinery, located at an industrial facility,
that is directly or indirectly related to process, manufacturing or
other industrial activities, which could be a source of pollutants
in any industrial stormwater discharge to groundwater. Source materials
include, but are not limited to, raw materials; intermediate products;
final products; waste materials; by-products; industrial machinery
and fuels, and lubricants, solvents, and detergents that are related
to process, manufacturing, or other industrial activities that are
exposed to stormwater.
Water resulting from precipitation (including rain and snow)
that runs off the land's surface, is transmitted to the subsurface,
or is captured by separate storm sewers or other sewage or drainage
facilities, or conveyed by snow removal equipment.
An excavation or embankment and related areas designed to
retain stormwater runoff. A stormwater management BMP may either be
normally dry (that is, a detention basin or infiltration system),
retain water in a permanent pool (a retention basin), or be planted
mainly with wetland vegetation (most constructed stormwater wetlands).
Any practice, technology, process, program, or other method
intended to control or reduce stormwater runoff and associated pollutants,
or to induce or control the infiltration or groundwater recharge of
stormwater or to eliminate illicit or illegal nonstormwater discharges
into stormwater conveyances.
Water flow on the surface of the ground or in storm sewers
resulting from precipitation.
The ocean and its estuaries, all springs, streams, wetlands,
and bodies of surface water or groundwater, whether natural or artificial,
within the boundaries of the State of New Jersey or subject to its
jurisdiction.
An area within 300 feet of any wetland.
Lands which are inundated or saturated by water at a magnitude,
duration and frequency sufficient to support the growth of hydrophytes.
Wetlands include lands with poorly drained or very poorly drained
soils as designated by the National Cooperative Soils Survey of the
Soil Conservation Service of the United States Department of Agriculture.
Wetlands include coastal wetlands and inland wetlands, including submerged
lands. The "New Jersey Pinelands Commission Manual for Identifying
and Delineating Pinelands Area Wetlands—a Pinelands Supplement
to the Federal Manual for Identifying and Delineating Jurisdictional
Wetlands," dated January, 1991, as amended, may be utilized in delineating
the extent of wetlands based on the definitions of "wetlands" and
"wetlands soils" contained in N.J.A.C. 7:50-2.11, 6.3, 6.4 and 6.5.
A.
Stormwater management measures for development regulated under this
chapter shall be designed to provide erosion control, groundwater
recharge, stormwater runoff quantity control and stormwater runoff
quality treatment in accordance with this chapter.
(1)
Major development shall meet the minimum design and performance standards
for erosion control established under the Soil Erosion and Sediment
Control Act, N.J.S.A. 4:24-39 et seq., and implementing rules at N.J.A.C.
2:90 and 16:25A.
B.
All development regulated under this chapter shall incorporate a maintenance plan for the stormwater management measures in accordance with § 204-9.
C.
Stormwater management measures shall avoid adverse impacts of concentrated
flow on habitat for threatened and endangered species in accordance
with N.J.A.C. 7:8-5.2(c) and N.J.A.C. 7:50-6.27 and 6.33.
D.
Tables 1, 2, and 3 below summarize the ability of stormwater best management practices identified and described in the New Jersey Stormwater BMP Manual to satisfy the green infrastructure, groundwater recharge, stormwater runoff quality and stormwater runoff quantity standards specified in § 204-3N, O, P, and Q. When designed in accordance with the most current version of the New Jersey Stormwater BMP Manual and this chapter, the stormwater management measures found in Tables 1, 2, and 3 are presumed to be capable of providing stormwater controls for the design and performance standards as outlined in the tables below. Upon amendments of the New Jersey Stormwater BMP Manual to reflect additions or deletions of BMPs meeting these standards, or changes in the presumed performance of BMPs designed in accordance with the New Jersey Stormwater BMP Manual, the NJDEP shall publish in the New Jersey Registers a notice of administrative change revising the applicable table. The most current version of the BMP Manual can be found on the NJDEP website at https://njstormwater.org/bmp_manual2.htm.
E.
Where the BMP tables at N.J.A.C. 7:8-5.2(f) differ with Tables 1, 2 and 3 below due to amendment, the BMP tables at N.J.A.C. 7:8-5.2(f) shall take precedence, except that in all cases the lowest point of infiltration must maintain a minimum separation of two feet to seasonal high water table as required by § 204-3H(2) unless otherwise noted.
|
Table 1: Green Infrastructure BMPs for Groundwater Recharge,
Stormwater Runoff Quality, and/or Stormwater Runoff Quantity
| ||||
|---|---|---|---|---|
|
Best Management Practice
|
Stormwater Runoff Quality TSS Removal Rate
(Percent)
|
Stormwater Runoff Quantity
|
Groundwater Recharge
|
Minimum Separation from Seasonal High Water Table
(Feet)
|
|
Cistern
|
0
|
Yes
|
No
|
—
|
|
Dry well(a)
|
0
|
No
|
Yes
|
2
|
|
Grass swale
|
50 or less
|
No
|
No
|
2(e)
1(f)
|
|
Green roof
|
0
|
Yes
|
No
|
—
|
|
Manufactured treatment device(a) (g)
|
50 or 80
|
No
|
No
|
Dependent upon the device
|
|
Pervious paving system(a)
|
80
|
Yes
|
Yes(b)
No(c)
|
2(b)
2(c)
|
|
Small-scale bioretention basin(a)
|
80 or 90
|
Yes
|
Yes(b)
No(c)
|
2(b)
1(c)
|
|
Small-scale infiltration basin(a)
|
80
|
Yes
|
Yes
|
2
|
|
Small-scale sand filter(a)
|
80
|
Yes
|
Yes
|
2
|
|
Vegetative filter strip
|
60-80
|
No
|
No
|
—
|
|
Table 2: Green Infrastructure BMPs for Stormwater Runoff Quantity
(or for Groundwater Recharge and/or Stormwater Runoff Quality with
a Variance from N.J.A.C. 7:8-5.3)
| ||||
|---|---|---|---|---|
|
Best Management Practice
|
Stormwater Runoff Quality TSS Removal Rate (Percent)
|
Stormwater Runoff Quantity
|
Groundwater Recharge
|
Minimum Separation from Seasonal High Water Table
(Feet)
|
|
Bioretention system
|
80 or 90
|
Yes
|
Yes(b)
No(c)
|
2(b)
1(c)
|
|
Infiltration basin
|
80
|
Yes
|
Yes
|
2
|
|
Sand filter(b)
|
80
|
Yes
|
Yes
|
2
|
|
Standard constructed wetland
|
90
|
Yes
|
No
|
2(i)
|
|
Wet pond(d)
|
50-90
|
Yes
|
No
|
2(i)
|
|
Table 3: BMPs for Groundwater Recharge, Stormwater Runoff Quality,
and/or Stormwater Runoff Quantity only with a Variance from N.J.A.C.
7:8-5.3
| ||||
|---|---|---|---|---|
|
Best Management Practice
|
Stormwater Runoff Quality TSS Removal Rate (Percent)
|
Stormwater Runoff Quantity
|
Groundwater Recharge
|
Minimum Separation from Seasonal High Water Table
(Feet)
|
|
Blue roof
|
0
|
Yes
|
No
|
N/A
|
|
Extended detention basin
|
40-60
|
Yes
|
No
|
2
|
|
Manufactured treatment device(h)
|
50 or 80
|
No
|
No
|
Dependent upon the device
|
|
Sand filter(c)
|
80
|
Yes
|
No
|
2
|
|
Subsurface gravel wetland
|
90
|
No
|
No
|
2
|
|
Wet pond
|
50-90
|
Yes
|
No
|
2(i)
|
|
NOTES to Tables 1, 2, and 3:
| |
|
(a)
|
Subject to the applicable contributory drainage area limitation specified at § 204-3N(2).
|
|
(b)
|
Designed to infiltrate into the subsoil.
|
|
(c)
|
Designed with underdrains, where stormwater percolates into
the underdrain through the soils and is not directed to the underdrain
by an outlet control structure.
|
|
(d)
|
Designed to maintain at least a ten-foot-wide area of native
vegetation along at least 50% of the shoreline and to include a stormwater
runoff retention component designed to capture stormwater runoff for
beneficial reuse, such as irrigation.
|
|
(e)
|
Designed with a slope of less than 2%.
|
|
(f)
|
Designed with a slope of equal to or greater than 2%.
|
|
(g)
|
Manufactured treatment devices that meet the definition of "green infrastructure" at § 204-2.
|
|
(h)
|
Manufactured treatment devices that do not meet the definition of "green infrastructure" at § 204-2.
|
|
(i)
|
The top elevation of the impermeable layer or liner must maintain
this two-foot minimum separation to the seasonal high water table.
|
F.
An alternative stormwater management measure, alternative removal rate, and/or alternative method to calculate the removal rate may be used if the design engineer demonstrates the capability of the proposed alternative stormwater management measure and/or the validity of the alternative rate or method to the municipality. A copy of any approved alternative stormwater management measure, alternative removal rate, and/or alternative method to calculate the removal rate shall be provided to the NJDEP and the Pinelands Commission in accordance with § 204-5B and C. Alternative stormwater management measures may be used to satisfy the requirements at § 204-3N only if the measures meet the definition of "green infrastructure" at § 204-2. Alternative stormwater management measures that function in a similar manner to a BMP listed at § 204-3N(2) are subject to the contributory drainage area limitation specified at § 204-3N(2) for that similarly functioning BMP. Alternative stormwater management measures approved in accordance with this subsection that do not function in a similar manner to any BMP listed at § 204-3N(2) shall have a contributory drainage area less than or equal to 2.5 acres, except for alternative stormwater management measures that function similarly to cisterns, grass swales, green roofs, standard constructed wetlands, vegetative filter strips, and wet ponds, which are not subject to a contributory drainage area limitation. Alternative measures that function similarly to standard constructed wetlands or wet ponds shall not be used for compliance with the stormwater runoff quality standard unless a variance in accordance with § 204-10 is granted from § 204-3N.
G.
Hydraulic impacts.
(1)
For all major development, groundwater mounding analysis shall be
required for purposes of assessing the hydraulic impacts of mounding
of the water table resulting from infiltration of stormwater runoff
from the maximum storm designed for infiltration. The mounding analysis
shall provide details and supporting documentation on the methodology
used. Groundwater mounds shall not cause stormwater or groundwater
to breakout to the land surface or cause adverse impacts to adjacent
water bodies, wetlands, or subsurface structures, including, but not
limited to, basements and septic systems. Where the mounding analysis
identifies adverse impacts, the stormwater management measure shall
be redesigned or relocated, as appropriate.
(2)
For all applicable minor development, a design engineer's certification
that each green infrastructure stormwater management measure will
not adversely impact basements or septic systems of the proposed development
shall be required.
H.
Design standards for stormwater management measures are as follows:
(1)
Stormwater management measures shall be designed to take into account
the existing site conditions, including, but not limited to, environmentally
critical areas; wetlands; wetland transition areas; flood-prone areas;
slopes; depth to seasonal high water table; soil type, permeability,
and texture; drainage area and drainage patterns; and the presence
of solution-prone carbonate rocks (limestone);
(2)
Stormwater management measures designed to infiltrate stormwater
shall be designed, constructed, and maintained to provide a minimum
separation of at least two feet between the elevation of the lowest
point of infiltration and the seasonal high water table;
(3)
Stormwater management measures designed to infiltrate stormwater
shall be sited in suitable soils verified by testing to have permeability
rates between one and 20 inches per hour. A factor of safety of two
shall be applied to the soil's permeability rate in determining
the infiltration measure's design permeability rate. If such
soils do not exist on the parcel proposed for development or if it
is demonstrated that it is not practical for engineering, environmental,
or safety reasons to site the stormwater infiltration measure(s) in
such soils, the stormwater infiltration measure(s) may be sited in
soils verified by testing to have permeability rates in excess of
20 inches per hour, provided that stormwater is routed through a bioretention
system prior to infiltration. Said bioretention system shall be designed,
installed, and maintained in accordance with the New Jersey Stormwater
BMP Manual;
(4)
The use of stormwater management measures that are smaller in size
and distributed spatially throughout a parcel, rather than the use
of a single, larger stormwater management measure, shall be required;
(5)
Methods of treating stormwater prior to entering any stormwater management
measure shall be incorporated into the design of the stormwater management
measure to the maximum extent practical;
(6)
To avoid sedimentation that may result in clogging and reduction
of infiltration capability and to maintain maximum soil infiltration
capacity, the construction of stormwater management measures that
rely upon infiltration shall be managed in accordance with the following
standards:
(a)
No stormwater management measure shall be placed into operation
until its drainage area has been completely stabilized. Instead, upstream
runoff shall be diverted around the measure and into separate, temporary
stormwater management facilities and sediment basins. Such temporary
facilities and basins shall be installed and utilized for stormwater
management and sediment control until stabilization is achieved in
accordance with N.J.A.C. 2:90;
(b)
If, for engineering, environmental, or safety reasons, temporary stormwater management facilities and sediment basins cannot be constructed on the parcel in accordance with Subsection H(6)(a) above, the stormwater management measure may be placed into operation prior to the complete stabilization of its drainage area provided that the measure's bottom during this period is constructed at a depth at least two feet higher than its final design elevation. When the drainage area has been completely stabilized, all accumulated sediment shall be removed from the stormwater management measure, which shall then be excavated to its final design elevation; and
(c)
To avoid compacting the soils below a stormwater management
measure designed to infiltrate stormwater, no heavy equipment, such
as backhoes, dump trucks, or bulldozers, shall be permitted to operate
within the footprint of the stormwater management measure. All excavation
required to construct a stormwater management measure that relies
on infiltration shall be performed by equipment placed outside the
footprint of the stormwater management measure. If this is not possible,
the soils within the excavated area shall be renovated and tilled
after construction is completed. Earthwork associated with stormwater
management measure construction, including excavation, grading, cutting,
or filling, shall not be performed when soil moisture content is above
the lower plastic limit;
(7)
Dry wells shall be designed to prevent access by amphibians and reptiles;
(8)
Stormwater management measures shall be designed to minimize maintenance, facilitate maintenance and repairs, and ensure proper functioning. Trash racks shall be installed at the intake to the outlet structure, as appropriate, and shall have parallel bars with one-inch spacing between the bars to the elevation of the water quality design storm established at § 204-3P(4). For elevations higher than the water quality design storm, the parallel bars at the outlet structure shall be spaced no greater than 1/3 the width of the diameter of the orifice or 1/3 the width of the weir, with a minimum spacing between bars of one inch and a maximum spacing between bars of six inches. In addition, the design of trash racks must comply with the requirements of § 204-7C(1);
(9)
Stormwater management measures shall be designed, constructed, and
installed to be strong, durable, and corrosion resistant. Measures
that are consistent with the relevant portions of the Residential
Site Improvement Standards at N.J.A.C. 5:21-7.3, 7.4, and 7.5 shall
be deemed to meet this requirement;
(10)
Stormwater management BMPs shall be designed to meet the minimum safety standards for stormwater management BMPs at § 204-7; and
(11)
The size of the orifice at the intake to the outlet from the
stormwater management BMP shall be a minimum of 2 1/2 inches
in diameter.
I.
Manufactured treatment devices may be used to meet the requirements of this chapter, provided the pollutant removal rates are verified by the New Jersey Corporation for Advanced Technology and certified by the NJDEP. Manufactured treatment devices that do not meet the definition of "green infrastructure" at § 204-2 may be used only under the circumstances described at § 204-3N(4).
J.
Any application for a new agricultural development that meets the definition of "major development" at N.J.A.C. 7:8-1.2 shall be submitted to the Soil Conservation District for review and approval in accordance with the requirements at § 204-3N, O, P, and Q and any applicable Soil Conservation District guidelines for stormwater runoff quantity and erosion control. For purposes of this subsection, "agricultural development" means land uses normally associated with the production of food, fiber, and livestock for sale. Such uses do not include the development of land for the processing or sale of food and the manufacture of agriculturally related products.
K.
If there is more than one drainage area, the groundwater recharge, stormwater runoff quality, and stormwater runoff quantity standards at § 204-3O, P, and Q shall be met in each drainage area, unless the runoff from the drainage areas coverage on site and no adverse environmental impact would occur as a result of compliance with any one or more of the individual standards being determined utilizing a weighted average of the results achieved for that individual standard across the affected drainage areas.
L.
Any stormwater management measure authorized under the municipal stormwater management plan or this chapter shall be reflected in a deed notice recorded in the Burlington County Clerk's office. A form of deed notice shall be submitted to the municipality for approval prior to filing. The deed notice shall contain a description of the stormwater management measure(s) used to meet the green infrastructure, groundwater recharge, stormwater runoff quality, and stormwater runoff quantity standards at § 204-3N, O, P, and Q and shall identify the location of the stormwater management measure(s) in NAD 1983 State Plane New Jersey FIPS 2900 US feet or latitude and longitude in decimal degrees. The deed notice shall also reference the maintenance plan required to be recorded upon the deed pursuant to § 204-9B(5). Prior to the commencement of construction, proof that the above required deed notice has been filed shall be submitted to the municipality. Proof that the required information has been recorded on the deed shall be in the form of either a copy of the complete recorded document or a receipt from the Clerk or other proof of recordation provided by the recording office. However, if the initial proof provided to the municipality is not a copy of the complete recorded document, a copy of the complete recorded document shall be provided to the municipality within 180 calendar days of the authorization granted by the municipality.
M.
A stormwater management measure approved under the municipal stormwater management plan or this chapter may be altered or replaced with the approval of the municipality, if the municipality determines that the proposed alteration or replacement meets the design and performance standards contained in § 204-3N, O, P, and Q and provides the same level of stormwater management as the previously approved stormwater management measure that is being altered or replaced. If an alteration or replacement is approved, a revised deed notice shall be submitted to the municipality for approval and subsequently recorded with the Burlington County Clerk's Office and shall contain a description and location of the stormwater management measure, as well as reference to the maintenance plan, in accordance with Subsection L above. Prior to the commencement of construction, proof that the above required deed notice has been filed shall be submitted to the municipality in accordance with Subsection L above.
N.
Green infrastructure standards.
(1)
This subsection specifies the types of green infrastructure BMPs
that may be used to satisfy the groundwater recharge, stormwater runoff
quality, and stormwater runoff quantity standards of this chapter.
(2)
To satisfy the groundwater recharge and stormwater runoff quality standards at § 204-3O and P, the design engineer shall utilize BMPs identified in Table 1 at § 204-3E and/or an alternative stormwater management measure approved in accordance with § 204-3F. The following green infrastructure BMPs are subject to the following maximum contributory drainage area limitations:
|
Best Management Practice
|
Maximum Contributory Drainage Area
|
|---|---|
|
Dry well
|
1 acre
|
|
Manufactured treatment device
|
2.5 acres
|
|
Pervious pavement system
|
Area of additional inflow cannot exceed three times the area
occupied by the BMP
|
|
Small-scale bioretention systems
|
2.5 acres
|
|
Small-scale infiltration basin
|
2.5 acres
|
|
Small-scale sand filter
|
2.5 acres
|
(4)
If a variance in accordance with § 204-10 is granted from the requirements of this subsection, then BMPs from Table 1, 2, or 3 at § 204-3E and/or an alternative stormwater management measure approved in accordance with § 204-3F may be used to meet the groundwater recharge, stormwater runoff quality, and stormwater runoff quantity standards at § 204-3O, P, and Q.
(5)
For separate or combined storm sewer improvement projects, such as sewer separation, undertaken by a government agency or public utility (for example, a sewerage company), the requirements of this subsection shall only apply to areas owned in fee simple by the government agency or utility, and areas within a right-of-way or easement held or controlled by the government agency or utility; the entity shall not be required to obtain additional property or property rights to fully satisfy the requirements of this subsection. Regardless of the amount of area of a separate or combined storm sewer improvement project subject to the green infrastructure requirements of this subsection, each project shall fully comply with the applicable groundwater recharge, stormwater runoff quality control, and stormwater runoff quantity standards at § 204-3O, P, and Q.
O.
Groundwater recharge standards.
(1)
This subsection contains the minimum design and performance standards
for groundwater recharge as follows.
(2)
For all major development, the total runoff volume generated from
the net increase in impervious surfaces by a ten-year, twenty-four-hour
storm shall be retained and infiltrated on site.
(3)
For minor development that involves the construction of four or fewer
dwelling units, the runoff generated from the total roof area of the
dwelling(s) by a ten-year, twenty-four-hour storm shall be retained
and infiltrated through installation of one or more green infrastructure
stormwater management measures designed in accordance with the New
Jersey Stormwater BMP Manual. Appropriate green infrastructure stormwater
management measures include, but are not limited to, dry wells, pervious
pavement systems, and small-scale bioretention systems, including
rain gardens.
(4)
For minor development that involves any nonresidential use and will
result in an increase of greater than 1,000 square feet of regulated
motor vehicle surfaces, the water quality design storm volume generated
from these surfaces shall be recharged on site.
P.
Stormwater runoff quality standards.
(1)
This subsection contains the minimum design and performance standards
to control stormwater runoff quality impacts of:
(a)
Major development;
(b)
Minor development that involves any nonresidential use and will
result in an increase of greater than 1,000 square feet of regulated
motor vehicle surfaces; and
(c)
Any development involving the grading, clearing, or disturbance
of an area in excess of 5,000 square feet within any five-year period.
(2)
Stormwater management measures shall be designed to reduce the post-construction load of total suspended solids (TSS) in stormwater runoff generated from the water quality design storm established at § 204-3P(4) as follows:
(a)
Eighty percent TSS removal of the anticipated load, expressed
as an annual average, shall be achieved for the stormwater runoff
from the net increase of motor vehicle surface.
(b)
If the surface is considered regulated motor vehicle surface
because the water quality treatment for an area of motor vehicle surface
that is currently receiving water quality treatment either by vegetation
or soil, by an existing stormwater management measure, or by treatment
at a wastewater treatment plant is to be modified or removed, the
project shall maintain or increase the existing TSS removal of the
anticipated load expressed as an annual average.
(3)
The requirement to reduce TSS does not apply to any stormwater runoff in a discharge regulated under a numeric effluent limitation for TSS imposed under the New Jersey Pollutant Discharge Elimination System (NJPDES) rules, N.J.A.C. 7:14A, or in a discharge specifically exempt under a NJPDES permit from this requirement. Every major development, including any that discharge into a combined sewer system, shall comply with Subsection P(2) above, unless the major development is itself subject to a NJPDES permit with a numeric effluent limitation for TSS or the NJPDES permit to which the major development is subject exempts the development from a numeric effluent limitation for TSS.
(4)
The water quality design storm is 1.25 inches of rainfall in two
hours. Water quality calculations shall take into account the distribution
of rain from the water quality design storm, as reflected in Table
4, below. The calculation of the volume of runoff may take into account
the implementation of stormwater management measures.
|
Table 4: Water Quality Design Storm Distribution
| |||||
|---|---|---|---|---|---|
|
Time
(Minutes)
|
Cumulative Rainfall
(Inches)
|
Time
(Minutes)
|
Cumulative Rainfall
(Inches)
|
Time
(Minutes)
|
Cumulative Rainfall
(Inches)
|
|
1
|
0.00166
|
41
|
0.1728
|
81
|
1.0906
|
|
2
|
0.00332
|
42
|
0.1796
|
82
|
1.0972
|
|
3
|
0.00498
|
43
|
0.1864
|
83
|
1.1038
|
|
4
|
0.00664
|
44
|
0.1932
|
84
|
1.1104
|
|
5
|
0.0083
|
45
|
0.2
|
85
|
1.117
|
|
6
|
0.00996
|
46
|
0.2117
|
86
|
1.1236
|
|
7
|
0.01162
|
47
|
0.2233
|
87
|
1.1302
|
|
8
|
0.01328
|
48
|
0.235
|
88
|
1.1368
|
|
9
|
0.01494
|
49
|
0.2466
|
89
|
1.1434
|
|
10
|
0.0166
|
50
|
0.2583
|
90
|
1.15
|
|
11
|
0.01828
|
51
|
0.2783
|
91
|
1.155
|
|
12
|
0.01996
|
52
|
0.2983
|
92
|
1.16
|
|
13
|
0.02164
|
53
|
0.3183
|
93
|
1.165
|
|
14
|
0.02332
|
54
|
0.3383
|
94
|
1.17
|
|
15
|
0.025
|
55
|
0.3583
|
95
|
1.175
|
|
16
|
0.03
|
56
|
0.4116
|
96
|
1.18
|
|
17
|
0.035
|
57
|
0.465
|
97
|
1.185
|
|
18
|
0.04
|
58
|
0.5183
|
98
|
1.19
|
|
19
|
0.045
|
59
|
0.5717
|
99
|
1.195
|
|
20
|
0.05
|
60
|
0.625
|
100
|
1.2
|
|
21
|
0.055
|
61
|
0.6783
|
101
|
1.205
|
|
22
|
0.06
|
62
|
0.7317
|
102
|
1.21
|
|
23
|
0.065
|
63
|
0.785
|
103
|
1.215
|
|
24
|
0.07
|
64
|
0.8384
|
104
|
1.22
|
|
25
|
0.075
|
65
|
0.8917
|
105
|
1.225
|
|
26
|
0.08
|
66
|
0.9117
|
106
|
1.2267
|
|
27
|
0.085
|
67
|
0.9317
|
107
|
1.2284
|
|
28
|
0.09
|
68
|
0.9517
|
108
|
1.23
|
|
29
|
0.095
|
69
|
0.9717
|
109
|
1.2317
|
|
30
|
0.1
|
70
|
0.9917
|
110
|
1.2334
|
|
31
|
0.1066
|
71
|
1.0034
|
111
|
1.2351
|
|
32
|
0.1132
|
72
|
1.015
|
112
|
1.2367
|
|
33
|
0.1198
|
73
|
1.0267
|
113
|
1.2384
|
|
34
|
0.1264
|
74
|
1.0383
|
114
|
1.24
|
|
35
|
0.133
|
75
|
1.05
|
115
|
1.2417
|
|
36
|
0.1396
|
76
|
1.0568
|
116
|
1.2434
|
|
37
|
0.1462
|
77
|
1.0636
|
117
|
1.245
|
|
38
|
0.1528
|
78
|
1.0704
|
118
|
1.2467
|
|
39
|
0.1594
|
79
|
1.0772
|
119
|
1.2483
|
|
40
|
0.166
|
80
|
1.084
|
120
|
1.25
|
(5)
If more than one BMP in series is necessary to achieve the required
80% TSS reduction for a site, the applicant shall utilize the following
formula to calculate TSS reduction:
|
R = A + B - (A x B)/100
|
|
Where:
| ||
|
R
|
=
|
Total TSS percent load removal from application of both BMPs;
|
|
A
|
=
|
The TSS percent removal rate applicable to the first BMP;
|
|
B
|
=
|
The TSS percent removal rate applicable to the second BMP.
|
(6)
Stormwater management measures shall also be designed to reduce, to the maximum extent feasible, the post-construction nutrient load of the anticipated load from the developed site in stormwater runoff generated from the water quality design storm established at § 204-3P(4). In achieving reduction of nutrients to the maximum extent feasible, the design of the site shall include green infrastructure BMPs that optimize nutrient removal while still achieving the performance standards in § 204-3O, P, and Q.
(7)
For all major development, stormwater management measures shall be designed to achieve a minimum of 65% reduction of the post-construction total nitrogen load from the developed site, including those permanent lawn or turf areas that are specifically intended for active human use as described at N.J.A.C. 7:50-6.24(c)3, in stormwater runoff generated from the water quality design storm established at § 204-3P(4). In achieving a minimum 65% reduction of total nitrogen, the design of the site shall include green infrastructure in accordance with the New Jersey Stormwater BMP Manual and shall optimize nutrient removal. The minimum 65% total nitrogen reduction may be achieved by using a singular stormwater management measure or multiple stormwater management measures in series.
(8)
In high pollutant loading areas (HPLAs) and/or areas where stormwater runoff is exposed to source material, as defined in § 204-2, the following additional water quality standards shall apply:
(a)
The areal extent and amount of precipitation falling directly
on or flowing over HPLAs and/or areas where stormwater is exposed
to source material shall be minimized through the use of roof covers,
canopies, curbing or other physical means to the maximum extent practical
in order to minimize the quantity of stormwater generated from HPLA
areas and areas where stormwater runoff is exposed to source material;
(b)
The stormwater runoff originating from HPLAs and/or areas where stormwater runoff is exposed to source material shall be segregated and prohibited from commingling with stormwater runoff originating from the remainder of the parcel unless it is first routed through one or more stormwater management measures required at Subsection P(8)(c) below;
(c)
The stormwater runoff from HPLAs and/or areas where stormwater runoff is exposed to source material shall incorporate stormwater management measures designed to reduce the post-construction load of TSS by at least 90% in stormwater runoff generated from the water quality design storm established at § 204-3P(4) using one or more of the measures identified at Subsection P(8)(c)[1] or [2] below. In meeting this requirement, the minimum 90% removal of total suspended solids may be achieved by utilizing multiple stormwater management measures in series:
[1]
Any measure designed in accordance with the New Jersey Stormwater
BMP Manual to remove total suspended solids. Any such measure must
be constructed to ensure that the lowest point of infiltration within
the measure maintains a minimum of two feet of vertical separation
from the seasonal high-water table; and
[2]
Other measures certified by the NJDEP, including a media filtration
system manufactured treatment device with a minimum 80% removal of
total suspended solids as verified by the New Jersey Corporation for
Advanced Technology; and
(d)
If the potential for contamination of stormwater runoff by petroleum products exists on site, prior to being conveyed to the stormwater management measure required at Subsection P(8)(c) above, the stormwater runoff from the HPLAs and areas where stormwater runoff is exposed to source material shall be conveyed through an oil/grease separator or other equivalent manufactured filtering device providing for the removal of petroleum hydrocarbons. The applicant shall provide the review agency with sufficient data to demonstrate acceptable performance of the device.
(9)
The Flood Hazard Area Control Act Rules at N.J.A.C. 7:13-4.1(c)1
establish 300-foot riparian zones along Category One waters, as designated
in the Surface Water Quality Standards at N.J.A.C. 7:9B, and certain
upstream tributaries to Category One waters. A person shall not undertake
a major development that is located within or discharges into a 300-foot
riparian zone without prior authorization from the Department under
N.J.A.C. 7:13.
(10)
Pursuant to the Flood Hazard Area Control Act Rules at N.J.A.C.
7:13-11.2(j)3.i, runoff from the water quality design storm that is
discharged within a 300-foot riparian zone shall be treated in accordance
with this subsection to reduce the post-construction load of total
suspended solids by 95% of the anticipated load from the developed
site, expressed as an annual average.
Q.
Stormwater runoff quantity standards.
(1)
This subsection contains the minimum design and performance standards
to control stormwater runoff quantity impacts related to applicable
major and minor development.
(2)
In order to control stormwater runoff quantity impacts, the design engineer shall, using the assumptions and factors for stormwater runoff calculations at § 204-4, complete one of the following:
(a)
Demonstrate through hydrologic and hydraulic analysis that for
stormwater leaving the site, post-construction runoff hydrographs
for the two-, ten-, and 100-year storm events do not exceed, at any
point in time, the preconstruction runoff hydrographs for the same
storm events;
(b)
Demonstrate through hydrologic and hydraulic analysis that there
is no increase, as compared to the preconstruction condition, in the
peak runoff rates of stormwater leaving the site for the two-, ten-
and 100-year storm events and that the increased volume or change
in timing of stormwater runoff will not increase flood damage at or
downstream of the site. This analysis shall include the analysis of
impacts of existing land uses and projected land uses assuming full
development under existing zoning and land use ordinances in the drainage
area;
(c)
Design stormwater management measures so that the post-construction
peak runoff rates for the two-, ten- and 100-year storm events are
50%, 75%, and 80%, respectively, of the preconstruction peak runoff
rates. The percentages apply only to the post-construction stormwater
runoff that is attributable to the portion of the site on which the
proposed development or project is to be constructed; or
(d)
In tidal flood hazard areas, stormwater runoff quantity analysis in accordance with Subsection Q(2)(a), (b), and (c) above is required unless the design engineer demonstrates through hydrologic and hydraulic analysis that the increased volume, change in timing, or increased rate of the stormwater runoff, or any combination of the three, will not result in additional flood damage below the point of discharge of the major development. No analysis is required if the stormwater is discharged directly into any ocean, bay, inlet, or the reach of any watercourse between its confluence with an ocean, bay, or inlet and downstream of the first water control structure.
(3)
The stormwater runoff quantity standards shall be applied at the
site's boundary to each abutting lot, roadway, watercourse, or
receiving storm sewer system.
(4)
There shall be no direct discharge of stormwater runoff from any
point or nonpoint source to any wetland, wetlands transition area,
or surface water body. In addition, stormwater runoff shall not be
directed in such a way as to increase the volume and rate of discharge
into any wetlands, wetlands transition area, or surface water body
from that which existed prior to development of the parcel.
(5)
To the maximum extent practical, there shall be no direct discharge
of stormwater runoff onto farm fields to protect farm crops from damage
due to flooding, erosion, and long-term saturation of cultivated crops
and cropland.
R.
As-built requirements for major development are as follows:
(1)
After all construction activities have been completed on the parcel
and finished grade has been established in each stormwater management
measure designed to infiltrate stormwater, replicate postdevelopment
permeability tests shall be conducted to determine if as-built soil
permeability rates are consistent with design permeability rates.
The results of such tests shall be submitted to the Municipal Engineer
or other appropriate reviewing engineer. If the results of the post-development
permeability tests fail to achieve the minimum required design permeability
rate, utilizing a factor of safety of two, the stormwater management
measure shall be renovated and retested until the required permeability
rates are achieved; and
(2)
After all construction activities and required testing have been
completed on the parcel, as-built plans, including as-built elevations
of all stormwater management measures, shall be submitted to the Municipal
Engineer or other appropriate reviewing engineer to serve as a document
of record. Based upon that engineer's review of the as-built
plans, all corrections or remedial actions deemed necessary due to
the failure to comply with design standards and/or for any reason
concerning public health or safety shall be completed by the applicant.
In lieu of review by the Municipal Engineer, the municipality may
engage a licensed professional engineer to review the as-built plans
and charge the applicant for all costs associated with such review.
A.
Stormwater runoff shall be calculated by the design engineer using
the USDA Natural Resources Conservation Service (NRCS) methodology,
including the NRCS Runoff Equation and Dimensionless Unit Hydrograph,
as described in Chapters 7, 9, 10, 15 and 16, Part 630, Hydrology
National Engineering Handbook, incorporated herein by reference as
amended and supplemented, except that the Rational Method for peak
flow and the Modified Rational Method for hydrograph computations
shall not be used. This methodology is additionally described in Technical
Release 55 - Urban Hydrology for Small Watersheds (TR-55), dated June
1986, incorporated herein by reference as amended and supplemented.
Information regarding the methodology is available from the Natural
Resources Conservation Service website at https://www.nrcs.usda.gov/Internet/FSE_DOCUMENTS/stelprdb1044171.pdf;
or at United States Department of Agriculture, Natural Resources Conservation
Service, 220 Davidson Avenue, Somerset, New Jersey 08873.
B.
In calculating stormwater runoff using the NRCS methodology, the
appropriate twenty-four-hour rainfall depths as developed for the
parcel by the National Oceanic and Atmospheric Administration, https://hdsc.nws.noaa.gov/hdsc/pfds/pfds_map_cont.html?bkmrk=nj,
shall be utilized.
C.
For the purpose of calculating runoff coefficients and groundwater
recharge, there is a presumption that the preconstruction condition
of a site or portion thereof is a wooded land use with good hydrologic
condition. A runoff coefficient or a groundwater recharge land cover
for an existing condition may be used on all or a portion of the site
if the design engineer verifies that the hydrologic condition has
existed on the site or portion of the site for at least five years
without interruption prior to the time of application. If more than
one land cover has existed on the site during the five years immediately
prior to the time of application, the land cover with the lowest runoff
potential shall be used for the computations. In addition, there is
the presumption that the site is in good hydrologic condition (if
the land use type is pasture, lawn, or park), with good cover (if
the land use type is woods), or with good hydrologic condition and
conservation treatment (if the land use type is cultivation).
D.
In computing preconstruction stormwater runoff, the design engineer
shall account for all significant land features and structures, such
as ponds, wetlands, depressions, hedgerows, or culverts, that may
reduce preconstruction stormwater runoff rates and volumes.
E.
In computing stormwater runoff from all design storms, the design
engineer shall consider the relative stormwater runoff rates and/or
volumes of pervious and impervious surfaces separately to accurately
compute the rates and volume of stormwater runoff from the site. To
calculate runoff from unconnected impervious cover, urban impervious
area modifications as described in the NRCS Technical Release 55 -
Urban Hydrology for Small Watersheds or other methods may be employed.
F.
If the invert of the outlet structure of a stormwater management
measure is below the flood hazard design flood elevation as defined
at N.J.A.C. 7:13, the design engineer shall take into account the
effects of tailwater in the design of structural stormwater management
measures.
G.
Groundwater recharge may be calculated in accordance with the New
Jersey Geological Survey Report GSR-32, A Method for Evaluating Groundwater-Recharge
Areas in New Jersey, incorporated herein by reference as amended and
supplemented. Information regarding the methodology is available from
the New Jersey Stormwater Best Management Practices Manual; at the
New Jersey Geological Survey website at https://www.nj.gov/dep/njgs/pricelst/gsreport/gsr32.pdf;
or at New Jersey Geological and Water Survey, 29 Arctic Parkway, PO
Box 420, Mail Code 29-01, Trenton, New Jersey 08625-0420.
A.
Technical guidance for stormwater management measures can be found
in the documents listed below, which are available to download from
the NJDEP's website at http://www.nj.gov/dep/stormwater/bmp_manual2.htm.
(1)
Guidelines for stormwater management measures are contained in the New Jersey Stormwater BMP Manual, as amended and supplemented. Information is provided on stormwater management measures such as, but not limited to, those listed in Tables 1, 2, and 3 of § 204-3E. The New Jersey Stormwater BMP Manual may be utilized as a guide in determining the extent to which stormwater management activities and measures meet the standards of this chapter.
(2)
Additional maintenance guidance is available on the NJDEP's
website at https://www.njstormwater.org/maintenance_guidance.htm.
B.
Submissions required for review by the NJDEP should be mailed to
the Division of Water Quality, New Jersey Department of Environmental
Protection, Mail Code 401-02B, PO Box 420, Trenton, New Jersey 08625-0420.
C.
Submissions required for review by the Pinelands Commission should
be emailed to appinfo@pinelands.nj.gov.
Site design features identified under § 204-3E, or alternative designs in accordance with § 204-3F, to prevent discharge of trash and debris from drainage systems shall comply with the following standard to control passage of solid and floatable materials through storm drain inlets. For purposes of this section, "solid and floatable materials" means sediment, debris, trash, and other floating, suspended, or settleable solids. For exemptions to this standard, see Subsection B below.
A.
Design engineers shall use one of the following grates whenever they
use a grate in pavement or another ground surface to collect stormwater
from that surface into a storm drain or surface water body under that
grate:
(1)
The New Jersey Department of Transportation (NJDOT) bicycle-safe
grate, which is described in Chapter 2.4 of the NJDOT Bicycle Compatible
Roadways and Bikeways Planning and Design Guidelines; or
(2)
A different grate, if each individual clear space in that grate has
an area of no more than seven square inches, or is no greater than
0.5 inch across the smallest dimension. Examples of grates subject
to this standard include grates in grate inlets, the grate portion
(non-curb-opening portion) of combination inlets, grates on storm
sewer manholes, ditch grates, trench grates, and grates of spacer
bars in slotted drains. Examples of ground surfaces include surfaces
of roads (including bridges), driveways, parking areas, bikeways,
plazas, sidewalks, lawns, fields, open channels, and stormwater system
floors used to collect stormwater from the surface into a storm drain
or surface water body.
(3)
For curb-opening inlets, including curb-opening inlets in combination
inlets, the clear space in that curb opening, or each individual clear
space if the curb opening has two or more clear spaces, shall have
an area of no more than seven square inches, or be no greater than
two inches across the smallest dimension.
B.
The standard in Subsection A above does not apply:
(1)
Where each individual clear space in the curb opening in existing
curb-opening inlet does not have an area of more than nine square
inches;
(2)
Where the municipality agrees that the standards would cause inadequate
hydraulic performance that could not practicably be overcome by using
additional or larger storm drain inlets;
(3)
Where flows from the water quality design storm established at § 204-3P(4) are conveyed through any device (e.g., end-of-pipe netting facility, manufactured treatment device, or a catch basin hood) that is designed, at a minimum, to prevent delivery of all solid and floatable materials that could not pass through one of the following:
(a)
A rectangular space 4 5/8 inches long and 1 1/2 inches
wide (this option does not apply for outfall netting facilities);
or
(b)
A bar screen having a bar spacing of 0.5 inch.
(c)
Note that these exemptions do not authorize any infringement
of requirements in the Residential Site Improvement Standards for
bicycle safe grates in new residential development (N.J.A.C. 5:21-4.18(b)2
and 7.4(b)1).
(4)
Where flows are conveyed through a trash rack that has parallel bars with one-inch spacing between the bars, to the elevation of the water quality design storm established at § 204-3P(4); or
(5)
Where the NJDEP determines, pursuant to the New Jersey Register of
Historic Places Rules at N.J.A.C. 7:4-7.2(c), that action to meet
this standard is an undertaking that constitutes an encroachment or
will damage or destroy the New Jersey Register listed historic property.
A.
This section sets forth requirements to protect public safety through
the proper design and operation of stormwater management BMPs. This
section applies to any new stormwater management BMP.
B.
The provisions of this section are not intended to preempt more stringent municipal or county safety requirements for new or existing stormwater management BMPs. Municipal and county stormwater management plans and ordinances may, pursuant to their authority, require existing stormwater management BMPs to be retrofitted to meet one or more of the safety standards in Subsection C(1), (2) or (3) below for trash racks, overflow grates, and escape provisions at outlet structures.
C.
Requirements for trash racks, overflow grates and escape provisions.
(1)
A trash rack is a device designed to catch trash and debris and prevent
the clogging of outlet structures. Trash racks shall be installed
at the intake to the outlet from the stormwater management BMP to
ensure proper functioning of the BMP outlets in accordance with the
following:
(a)
The trash rack shall have parallel bars, with no greater than
six-inch spacing between the bars;
(b)
The trash rack shall be designed so as not to adversely affect
the hydraulic performance of the outlet pipe or structure;
(c)
The average velocity of flow through a clean trash rack is not
to exceed 2.5 feet per second under the full range of stage and discharge.
Velocity is to be computed on the basis of the net area of opening
through the rack; and
(d)
The trash rack shall be constructed of rigid, durable, and corrosion-resistant
material and designed to withstand a perpendicular live loading of
300 pounds per square foot.
(2)
An overflow grate is designed to prevent obstruction of the overflow
structure. If an outlet structure has an overflow grate, the grate
shall comply with the following requirements:
(a)
The overflow grate shall be secured to the outlet structure
but removable for emergencies and maintenance.
(b)
The overflow grate spacing shall be no greater than two inches
across the smallest dimension.
(c)
The overflow grate shall be constructed of rigid, durable, and
corrosion-resistant material, and shall be designed to withstand a
perpendicular live loading of 300 pounds per square foot.
(3)
Stormwater management BMPs shall include escape provisions as follows:
(a)
If a stormwater management BMP has an outlet structure, escape provisions shall be incorporated in or on the structure. Escape provisions include the installation of permanent ladders, steps, rungs, or other features that provide easily accessible means of egress from stormwater management BMPs. With the prior approval of the municipality pursuant to Subsection D below, a freestanding outlet structure may be exempted from this requirement;
(b)
Safety ledges shall be constructed on the slopes of all new stormwater management BMPs having a permanent pool of water deeper than 2 1/2 feet. Safety ledges shall be comprised of two steps. Each step shall be four feet to six feet in width. One step shall be located approximately 2 1/2 feet below the permanent water surface, and the second step shall be located one foot to 1 1/2 feet above the permanent water surface. See Subsection E below for an illustration of safety ledges in a stormwater management BMP; and
(c)
In new stormwater management BMPs, the maximum interior slope
for an earthen dam, embankment, or berm shall not be steeper than
three horizontal to one vertical.
D.
Variance or exemption from safety standard. A variance or exemption
from the safety standards for stormwater management BMPs may be granted
only upon a written finding by the municipality that the variance
or exemption will not constitute a threat to public safety.
E.
Safety ledge illustration.
|
Figure 1. Elevation View - Basin Safety Ledge Configuration
 |
A.
Submission of site development stormwater plan.
(1)
Any application for major development approval shall include a site development stormwater plan containing all information required in § 204-8C.
(2)
Any application for minor development approval that is subject to this chapter shall include a site development stormwater plan containing all information required in § 204-8D.
(3)
The site development stormwater plan shall demonstrate that the proposed
development meets the standards of this chapter.
(4)
The site development stormwater plan shall contain comprehensive hydrologic and hydraulic design calculations for the predevelopment and post-development conditions for the design storms specified in § 204-3P(4). The standards for groundwater recharge and stormwater runoff rate, volume and quality required by § 204-3O, P, and Q and shall be met using the methods, calculations and assumptions provided in § 204-4.
(6)
The applicant shall submit two hard copies and one digital copy of
the site development stormwater plan. All required engineering plans
shall be in CAD Format 15 or higher, registered and rectified to NAD
1983 State Plane New Jersey FIPS 2900 US feet or Shape Format NAD
1983 State Plane New Jersey FIPS 2900 US feet. All other required
documents shall be submitted in both paper and commonly used electronic
file formats such as pdf, word processing, database or spreadsheet
files.
B.
Site development stormwater plan approval. The site development stormwater
plan shall be reviewed as a part of the development review process
by the municipal board or official from whom municipal approval is
sought. That municipal board or official shall consult the engineer
retained by the Planning and/or Zoning Board (as appropriate) to determine
if all the checklist requirements have been satisfied and to determine
if the project meets the standards set forth in this chapter.
C.
Checklist requirements for major development. Any application for
major development approval shall include a site development stormwater
plan containing, at minimum, the following information.
(1)
Topographic base map. The site development stormwater plan shall
contain a topographic base map of the site that extends a minimum
of 300 feet beyond the limits of the proposed development, at a scale
of one inch equals 200 feet or greater, showing one-foot contour intervals.
The map shall indicate the following: existing surface water drainage,
shorelines, steep slopes, soils, highly erodible soils, perennial
or intermittent streams that drain into or upstream of any Category
One or Pinelands waters, wetlands and floodplains along with any required
wetlands transition areas, marshlands and other wetlands, pervious
or vegetative surfaces, existing surface and subsurface human-made
structures, roads, bearing and distances of property lines, and significant
natural and man-made features not otherwise shown. Medford Lakes Borough
or the Pinelands Commission may require upstream tributary drainage
system information as necessary.
(2)
Environmental site analysis. The site development stormwater plan
shall contain a written description along with the drawings of the
natural and human-made features of the site and its environs. This
description shall include:
(a)
A discussion of environmentally critical areas, soil conditions,
slopes, wetlands, waterways and vegetation on the site. Particular
attention shall be given to unique, unusual or environmentally sensitive
features and to those features that provide particular opportunities
for or constraints on development; and
(b)
Detailed soil and other environmental conditions on the portion
of the site proposed for installation of any stormwater management
measures, including, at a minimum:
[1]
A soils report based on on-site soil tests;
[2]
Location and spot elevations in plan view of all test pits and
permeability tests;
[3]
Permeability test data and calculations;
[4]
Any other required soil or hydrogeologic data (e.g., mounding
analyses results) correlated with location and elevation of each test
site;
[5]
A cross section of all proposed stormwater management measures
with side-by-side depiction of soil profile drawn to scale and seasonal
high water table elevation identified; and
[6]
Any other information necessary to demonstrate the suitability
of the specific proposed stormwater management measures relative to
the environmental conditions on the portion(s) of the site proposed
for implementation of those measures.
(3)
Project description and site plan(s). The site development stormwater
plan shall contain a map (or maps), at the same scale as the topographical
base map, indicating the location of existing and proposed buildings,
roads, parking areas, utilities, structural facilities for stormwater
management and sediment control, and other permanent structures. The
map(s) shall also clearly show areas where alterations will occur
in the natural terrain and cover, including lawns and other landscaping,
and seasonal high groundwater elevations. A written description of
the site plan and justification for proposed changes in natural conditions
shall also be provided.
(4)
Land use planning and source control plan. The site development stormwater
plan shall contain a land use planning and source control plan demonstrating
compliance with the erosion control, groundwater recharge, stormwater
runoff quantity control and stormwater quality treatment required
by this chapter. This shall include, but is not limited to:
(5)
Stormwater management facilities map. The site development stormwater
plan shall contain a stormwater management facilities map, at the
same scale as the topographic base map, depicting the following information:
(a)
The total area to be disturbed, paved and/or built upon, proposed
surface contours, land area to be occupied by the stormwater management
facilities and the type of vegetation thereon, and details of the
proposed plan to manage and recharge stormwater; and
(b)
Details of all stormwater management facility designs, during
and after construction, including discharge provisions, discharge
capacity for each outlet at different levels of detention (if applicable)
and emergency spillway provisions with maximum discharge capacity
of each spillway.
D.
Checklist requirements for minor development. Any application for
minor development approval that is subject to this chapter shall include
a site development stormwater plan, certified by a design engineer,
containing, at minimum, the following information:
(1)
All existing and proposed development, including limits of clearing
and land disturbance.
(2)
All existing and proposed lot lines.
(3)
All wetlands and required wetland transition areas.
(4)
The type and location of each green infrastructure stormwater management
measure.
E.
Exception from submission requirements. With the exception of Subsection C(7) and D(7) above, the municipality may modify or waive any required element of the site development stormwater plan, provided that sufficient information can be provided to demonstrate compliance with the standards of this chapter. However, application information required in accordance with the Pinelands CMP [N.J.A.C. 7:50-4.2(b)] shall be submitted to the Pinelands Commission, unless the Executive Director of the Pinelands Commission waives or modifies the application requirements.
B.
The maintenance plan shall include the following:
(1)
Specific preventative maintenance tasks and schedules; cost estimates,
including estimated cost of sediment, debris, or trash removal; and
the name, address, and telephone number of the person or persons responsible
for preventative and corrective maintenance (including replacement).
The plan shall contain information on BMP location, design, ownership,
maintenance tasks and frequencies, and other details as specified
in Chapter 8 of the NJ BMP Manual, as well as the tasks specific to
the type of BMP, as described in the applicable chapter containing
design specifics.
(2)
Responsibility for maintenance of stormwater management measures
approved as part of an application for major development shall not
be assigned or transferred to the owner or tenant of an individual
property, unless such owner or tenant owns or leases the entire site
subject to the major development approval. The individual property
owner may be assigned incidental tasks, such as weeding of a green
infrastructure BMP, provided the individual agrees to assume these
tasks; however, the individual cannot be legally responsible for all
the maintenance required.
(3)
Responsibility for maintenance of stormwater management measures
approved as part of an application for minor development may be assigned
or transferred to the owner or tenant of the parcel.
(4)
If the maintenance plan identifies a person other than the property
owner (for example, a developer, a public agency or homeowners'
association) as having the responsibility for maintenance, the plan
shall include documentation of such person's or entity's
agreement to assume this responsibility, or of the owner's obligation
to dedicate a stormwater management facility to such person under
an applicable ordinance or regulation.
(5)
If the person responsible for maintenance identified under Subsection B(1) above is not a public agency, the maintenance plan and any future revisions based on § 204-9C(2)(b) shall be recorded upon the deed of record for each property on which the maintenance described in the maintenance plan must be undertaken.
(6)
For all major development, the following additional standards apply:
(a)
The maintenance plan shall include accurate and comprehensive
drawings of all stormwater management measures on a parcel, including
the specific latitude and longitude and block/lot number of each stormwater
management measure. Maintenance plans shall specify that an inspection,
maintenance, and repair report will be updated and submitted annually
to the municipality;
(b)
Stormwater management measure easements shall be provided by
the property owner as necessary for facility inspections and maintenance
and preservation of stormwater runoff conveyance, infiltration, and
detention areas and facilities. The purpose of the easement shall
be specified in the maintenance agreement; and
(c)
An adequate means of ensuring permanent financing of the inspection,
maintenance, repair, and replacement plan shall be implemented and
shall be detailed in the maintenance plan. Financing methods shall
include, but not be limited to:
[1]
The assumption of the inspection and maintenance program by
a municipality, county, public utility, or homeowners' association;
[2]
The required payment of fees to a municipal stormwater fund
in an amount equivalent to the cost of both ongoing maintenance activities
and necessary structural replacements.
(7)
For all minor development, maintenance plans shall be required for
all stormwater management measures installed in accordance with this
chapter and shall include, at a minimum, the following information:
C.
General maintenance and repair.
(1)
Preventative and corrective maintenance shall be performed to maintain
the function of the stormwater management measure, including, but
not limited to, repairs or replacement to the structure; removal of
sediment, debris, or trash; restoration of eroded areas; snow and
ice removal; fence repair or replacement; restoration of vegetation;
and repair or replacement of nonvegetated linings.
(2)
The person responsible for maintenance identified under § 204-9B(2) shall perform all of the following requirements:
(a)
Maintain a detailed log of all preventative and corrective maintenance
for the structural stormwater management measures incorporated into
the design of the development, including a record of all inspections
and copies of all maintenance-related work orders;
(b)
Evaluate the effectiveness of the maintenance plan at least
once per year and adjust the plan and the deed as needed; and
(4)
In the event that the stormwater management facility becomes a danger
to public safety or public health, or if it is in need of maintenance
or repair, the municipality shall so notify the responsible person
in writing. Upon receipt of that notice, the responsible person shall
have 14 days to effect maintenance and repair of the facility in a
manner that is approved by the Municipal Engineer or his designee.
The municipality, in its discretion, may extend the time allowed for
effecting maintenance and repair for good cause. If the responsible
person fails or refuses to perform such maintenance and repair, the
municipality or county may immediately proceed to do so and shall
bill the cost thereof to the responsible person. Nonpayment of such
bill may result in a lien on the property.
D.
Nothing in this section shall preclude the municipality in which
the major development is located from requiring the posting of a performance
or maintenance guarantee in accordance with N.J.S.A. 40:55D-53.
A.
The exemptions, exceptions, applicability standards, and waivers
of strict compliance contained in the NJDEP Stormwater Management
Regulations at N.J.A.C. 7:8-1.1 et seq. shall not apply within the
Pinelands Area except in accordance with this section.
B.
The municipal review agency may grant a variance from the design
and performance standards for stormwater management measures set forth
in its municipal stormwater management plan and this chapter, provided
that:
(1)
No variances shall be granted from § 204-3Q(4), which prohibits the direct discharge of stormwater runoff to any wetlands, wetlands transition area, or surface water body and the direction of stormwater runoff in such a way as to increase in volume and rate of discharge into any wetlands, wetlands transition area, or surface water body from that which existed prior to development of the parcel;
(2)
The municipal stormwater plan includes a mitigation plan in accordance
with N.J.A.C. 7:8-4.2(c)11 and N.J.A.C. 7:50-3.39(a)2viii;
(3)
The applicant demonstrates that it is technically impracticable to
meet any one or more of the design and performance standards on site.
For the purposes of this analysis, technical impracticability exists
only when the design and performance standard cannot be met for engineering,
environmental, or safety reasons. A municipality's approval of
a variance shall apply to an individual drainage area and design and
performance standard and shall not apply to an entire site or project,
unless an applicant provides the required analysis for each drainage
area within the site and each design and performance standard;
(4)
The applicant demonstrates that the proposed design achieves the
maximum possible compliance with the design and performance standards
of this chapter on site; and
(5)
A mitigation project is implemented, in accordance with the following:
(a)
All mitigation projects shall be located in the Pinelands Area
and in the same HUC-14 as the parcel proposed for development. If
the applicant demonstrates that no such mitigation project is available,
the municipality may approve a variance that provides for mitigation
within the same HUC-11 as the parcel proposed for development, provided
the mitigation project is located in the Pinelands Area.
(b)
The proposed mitigation project shall be consistent with the municipal stormwater management plan certified by the Pinelands Commission. If said stormwater management plan does not identify appropriate parcels or projects where mitigation may occur, the applicant may propose a mitigation project that meets the criteria in Subsection B(5)(a) above.
(c)
The mitigation project shall be approved no later than preliminary
or final site plan approval of the major development.
(d)
The mitigation project shall be constructed prior to, or concurrently
with, the development receiving the variance.
(f)
If the variance that resulted in the mitigation project being required is from the green infrastructure standards at § 204-3N, then the mitigation project must use green infrastructure BMPs in Table 1 contained at § 204-3E, and/or an alternative stormwater management measure approved in accordance with § 204-3F that meets the definition of "green infrastructure" to manage an equivalent or greater area of impervious surface and an equivalent or greater area of motor vehicle surface as the area of the major development subject to the variance. Grass swales and vegetative filter strips may only be used in the mitigation project if the proposed project additionally includes a green infrastructure BMP other than a grass swale or vegetative filter strip. The green infrastructure used in the mitigation project must be sized to manage the water quality design storm established at § 204-3P(4), at a minimum, and is subject to the applicable contributory drainage area limitation specified at § 204-3N(2), as applicable.
(h)
A variance from the stormwater runoff quality standards at § 204-3P may be granted if the following are met:
[1]
The total drainage area of motor vehicle surface managed by
the mitigation project(s) must equal or exceed the drainage area of
the area of the major development subject to the variance and must
provide sufficient TSS removal to equal or exceed the deficit resulting
from granting the variance for the major development; and
(i)
A variance from the stormwater runoff quantity standards at § 204-3Q may be granted if the following are met:
[1]
The applicant demonstrates, through hydrologic and hydraulic
analysis, including the effects of the mitigation project, that the
variance will not result in increased flooding damage below each point
of discharge of the major development;
[2]
The mitigation project indirectly discharges to the same watercourse
and is located upstream of the major development subject to the variance;
and
[3]
The mitigation project provides peak flow rate attenuation in accordance with § 204-3Q(2)(c) for an equivalent or greater area than the area of the major development subject to the variance. For the purposes of this demonstration, "equivalent" includes both size of the area and percentage of impervious surface and/or motor vehicle surface.
(j)
The applicant or the entity assuming maintenance responsibility for the associated major development shall be responsible for preventive and corrective maintenance (including replacement) of the mitigation project and shall be identified as such in the maintenance plan established in accordance with § 204-9. This responsibility is not transferable to any entity other than a public agency, in which case a written agreement with that public agency must be submitted to the review agency.
C.
Any approved variance shall be submitted by the municipal review
agency to the county review agency and the NJDEP, by way of a written
report describing the variance, as well as the required mitigation,
within 30 days of the approval.
Any person, firm, corporation, association or legal party whatsoever who or which shall violate, or authorize or procure a violation, or cause to be violated, any provision of this chapter shall, upon conviction thereof, be punishable as provided under the general penalty provisions found at § 1-15 of this Code. This, however, shall not apply against any municipal employee or officer that authorizes action by permit or otherwise in the ordinary course of their duties.
