[Adopted 10-11-2005 by Ord. No. 2005-36[1]]
[1]
Editor's Note: This ordinance also repealed
former Ch. 262, Surface Water Runoff, adopted 6-24-1975 by Ord. No.
75-11 (Ch. 135 of the 1977 Code), as amended 12-29-1977 by Ord. No.
77-21.
A.
Policy statement. Flood control, groundwater recharge
and pollutant reduction shall be achieved through the use of stormwater
management measures, including green infrastructure, best management
practices (GI BMPS), and nonstructural stormwater management strategies.
GI BMPs and low impact development (LID) 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. GI BMPs and LID 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.
[Amended 2-23-2021 by Ord. No. 2021-01]
B.
Purpose. It is the purpose of this article to establish minimum stormwater management requirements and controls for "major development," as defined in § 262-2.
C.
D.
Compatibility with other permit and ordinance requirements.
Development approvals issued pursuant to this article 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 article
shall be held to be the minimum requirements for the promotion of
the public health, safety and general welfare. This article is not
intended to interfere with, abrogate or annul any other ordinances,
rule or regulation, statute or other provision of law except that,
where any provision of this article 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.
[Amended 2-23-2021 by Ord. No. 2021-01]
[Amended 2-23-2021 by Ord. No. 2021-01]
For the purpose of this article, the following
terms, phrases words, and their derivations shall have the meanings
stated herein unless their use in the text of this article 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 Stormwater
Management Rules at N.J.A.C. 7:8-1.2.
Those areas within boundaries incorporated by reference or
revised by the Department in accordance with N.J.A.C. 7:7-13.16.
The map used by the Department to identify the location of
Coastal Planning Areas, CAFRA Centers, CAFRA Cores and CAFRA Nodes.
The CAFRA Planning Map is available on the Department's Geographic
Information System (GIS).
An infiltration system, sand filter designed to infiltrate,
standard constructed wetland, or wet pond, established in accordance
with N.J.A.C. 7:8-4.2(c)14, that is designed and constructed in accordance
with the New Jersey Stormwater Best Management Practices Manual, or
an alternate design, approved in accordance with N.J.A.C. 7:8-5.2(g),
for an infiltration system, sand filter designed to infiltrate, standard
constructed wetland, or wet pond and that complies with the requirements
of this article.
The increase in soil bulk density.
The area from which stormwater runoff drains to a stormwater
management measure, not including the area of stormwater management
measure itself.
A pedestrian-oriented area of commercial and civic uses serving
the surrounding municipality, generally including housing and access
to public transportation.
An agency designated by the Board of County Commissioners
to review municipal stormwater management plans and implementing ordinance(s).
The County review agency may either be:
The New Jersey Department of Environmental Protection.
A state development and redevelopment plan center as designated
by the State Planning Commission such as urban, regional, town, village
or hamlet.
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 division of a parcel of land into two or more parcels,
the construction, reconstruction, conversion, structural alteration,
relocation or enlargement of any building or structure, any mining
excavation or landfill, and any use or change in the use of any building
or other structure, or land or extension of use of land, for which
permission is required under the Municipal Land Use Law, N.J.S.A.
40:55D-1 et seq. In the case of development of agricultural lands,
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
are not considered disturbance for the purposes of this definition.
A geographic area within which stormwater, sediments or dissolved
materials drain to a particular receiving water body or to a particular
point along a receiving water body.
A neighborhood designated by the Urban Coordinating Council
"in consultation and in conjunction with" the New Jersey Redevelopment
Authority pursuant to N.J.S.A.A 55:19-69.
The following areas where the physical alteration of the
land is in some way restricted, either through regulation, easement,
deed restriction or ownership, such as: wetlands, floodplains, threatened
and endangered species sites or designated habitats, and parks and
preserves. Habitats of endangered or threatened species are identified
using the Department's Landscape Project as approved by the Department's
Endangered and Nongame Species Program.
An area or feature which is of significant environmental
value, including but not limited to: stream corridors; natural heritage
priority sites; habitat 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 Department's Landscape
Project as approved by the Department's 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:
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.
A surface that has been covered with a layer of material
so that it is highly resistant to infiltration by water.
The process by which water seeps into the soil from precipitation.
One or more public entities having stormwater management
planning authority designated by the regional stormwater management
planning committee pursuant to N.J.A.C. 7:8-3.2, that serves as the
primary representative of the committee.
An individual development, as well as multiple developments
that individually or collectively result in:
The disturbance of one or more acres of land since February
2, 2004;
The creation of 1/4 acre or more of regulated impervious surface
since February 2, 2004;
The creation of 1/4 acre or more of regulated motor vehicle
surface since March 2, 2021; or
A combination of Subsection A(2) and (3) of this definition
that totals an area of 1/4 acre or more. The same surface shall not
be counted twice when determining if the combination area equals 1/4
acre or more.
"Major development" includes all developments that are part
of a common plan of development or sale (for example, phased residential
development) that collectively or individually meet any one or more
of Subsection A(1), (2), (3), or (4) of this definition. Projects
undertaken by any government agency that otherwise meet the definition
of "major development" but which do not require approval under the
Municipal Land Use Law, N.J.S.A. 40:55D-1 et seq., are also considered
"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.
Any city, borough, town, township or village.
The manual maintained by the Department providing, in part, design specifications, removal rates, calculation methods, and soil testing procedures approved by the Department as being capable of contributing to the achievement of the stormwater management standards specified in this article. The BMP Manual is periodically amended by the Department 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 Department's determination as to the ability of that best management practice to contribute to compliance with the standards contained in this article. Alternative stormwater management measures, removal rates, or calculation methods may be utilized, subject to any limitations specified in this article, provided the design engineer demonstrates to the municipality, in accordance with § 262-4 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 article.
An area designated by the State Planning Commission concentrating
facilities and activities which are not organized in a compact form.
A chemical element or compound, such as nitrogen or phosphorus,
which is essential to and promotes the development of organisms.
Any individual, corporation, company, partnership, firm,
association, Township of Hillsborough or political subdivision of
this state and any state, interstate or federal agency.
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 of impervious surface;
The total area of impervious surface collected by a new stormwater
conveyance system (for the purpose of this definition, a "new stormwater
conveyance system" is a stormwater conveyance system that is constructed
where one did not exist immediately prior to its construction or an
existing system for which a new discharge location is created);
The total area of impervious surface proposed to be newly collected
by an existing stormwater conveyance system; and/or
The total area of impervious surface collected by an existing
stormwater conveyance system where the capacity of that conveyance
system is increased.
Any of the following, alone or in combination:
The total area of motor vehicle surface that is currently receiving
water;
A net increase in motor vehicle surface; and/or 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.
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 a major development is to occur
or has occurred.
All unconsolidated mineral and organic material of any origin.
An area delineated on the State Plan Policy Map and adopted
by the State Planning Commission that is intended to be the focus
for much of the state's future redevelopment and revitalization efforts.
The geographic application of the State Development and Redevelopment
Plan's goals and statewide policies, and the official map of these
goals and policies.
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 basin may either
be normally dry (that is, a detention basin or infiltration basin),
retain water in a permanent pool (a retention basin) or be planted
mainly with wetland vegetation (most constructed stormwater wetlands).
Any structural or nonstructural strategy, 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.
A public body authorized by legislation to prepare stormwater
management plans.
The geographic area for which a stormwater management planning
agency is authorized to prepare stormwater management plans, or a
specific portion of that area identified in a stormwater management
plan prepared by that agency.
Water flow on the surface of the ground or in storm sewers
resulting from precipitation.
A flood hazard area in which the flood elevation resulting
from the two-, ten-, or 100-year storm, as applicable, is governed
by tidal flooding from the Atlantic Ocean. Flooding in a tidal flood
hazard area may be contributed to, or influenced by, stormwater runoff
from inland areas, but the depth of flooding generated by the tidal
rise and fall of the Atlantic Ocean is greater than flooding from
any fluvial sources. In some situations, depending upon the extent
of the storm surge from a particular storm event, a flood hazard area
may be tidal in the 100-year storm, but fluvial in more frequent storm
events.
[Amended 3-8-2022 by Ord. No. 2022-01]
A neighborhood given priority access to state resources through
the New Jersey Redevelopment Authority.
A zone designated by the New Jersey Enterprise Zone Authority
pursuant to the New Jersey Urban Enterprise Zones Act, N.J.S.A. 52:27H-60
et seq.
Peviously developed portions of areas:
A structure within, or adjacent to, a water, which intentionally
or coincidentally alters the hydraulic capacity, the flood elevation
resulting from the two-, ten-, or 100-year storm, flood hazard area
limit, and/or floodway limit of the water. Examples of a water control
structure may include a bridge, culvert, dam, embankment, ford (if
above grade), retaining wall, and weir.
The ocean and its estuaries, all springs, streams, wetlands
and bodies of surface or groundwater, whether natural or artificial,
within the boundaries of the State of New Jersey or subject to its
jurisdiction.
An area that is inundated or saturated by surface water or
groundwater at a frequency and duration sufficient to support, and
that under normal circumstances does support, a prevalence of vegetation
typically adapted for life in saturated soil conditions, commonly
known as "hydrophytic vegetation."
Design and performance standards for stormwater
management measures.
A.
Stormwater management measures for major development
shall be designed to meet the erosion control, groundwater recharge,
stormwater runoff quantity control and stormwater runoff quality treatment
standards as follows:
[Amended 2-23-2021 by Ord. No. 2021-01; 3-8-2022 by Ord. No. 2022-01]]
(1)
The
minimum standards for erosion control are those 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.
(2)
The
minimum standards for groundwater recharge, stormwater quality, and
stormwater runoff quantity shall be met by incorporating green infrastructure.
B.
The standards in this article apply only to new major
development and are intended to minimize the impact of stormwater
runoff on water quality and water quantity in receiving water bodies
and maintain groundwater recharge. The standards do not apply to new
major development to the extent that alternative design and performance
standards are applicable under a regional stormwater management plan
or water quality management plan adopted in accordance with Department
rules.
A.
The development shall incorporate a maintenance plan for the stormwater management measures incorporated into the design of a major development in accordance with § 262-10.
B.
Stormwater management measures shall avoid adverse
impacts of concentrated flow on habitat for threatened and endangered
species as documented in the Department's Landscape Project or Natural
Heritage Database established under N.J.S.A. 13:1B-15.147 through
13:1B-15.150, particularly Helonias bullata (swamp pink) and/or Clemmys
muhlenbergii (bog turtle).
C.
The following linear development projects are exempt from the groundwater recharge, stormwater runoff quantity and stormwater runoff quality requirements of § 262-4P, Q, and R:
[Amended 2-23-2021 by Ord. No. 2021-01]
(1)
The construction of an underground utility line, provided
that the disturbed areas are revegetated upon completion;
(2)
The construction of an aboveground utility line, provided
that the existing conditions are maintained to the maximum extent
practicable; and
(3)
The construction of a public pedestrian access, such
as a sidewalk or trail with a maximum width of 14 feet, provided that
the access is made of permeable material.
D.
Waivers.
[Amended 2-22-2011 by Ord. No. 2011-04; 2-23-2021 by Ord. No. 2021-01]
(1)
A waiver from strict compliance from the green infrastructure, groundwater recharge, stormwater runoff quantity and stormwater runoff quality requirements of § 262-4O, P, Q, and R may be obtained for the enlargement of an existing public roadway or railroad or the construction or enlargement of a public pedestrian access, provided that the following conditions are met:
(a)
The applicant demonstrates that there is a public need for the
project that cannot be accomplished by any other means;
(d)
The applicant demonstrates that it does not own or have other rights to areas, including the potential to obtain through condemnation lands not falling under Subsection D(1)(c) above within the upstream drainage area of the receiving stream, that would provide additional opportunities to mitigate the requirements of § 262-4O, P, Q, and R that were not achievable on-site.
E.
Tables 1 through 3 below summarize the ability of stormwater best management practices identified and described in the New Jersey Stormwater Best Management Practices Manual to satisfy the green infrastructure, groundwater recharge, stormwater runoff quality and stormwater runoff quantity standards specified in § 262-4O,P, Q, and R. When designed in accordance with the most current version of the New Jersey Stormwater Best Management Practices Manual, the stormwater management measures found at N.J.A.C. 7:8-5.2(f), Tables 5-1, 5-2 and 5-3, and listed below 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 Best Management Practices 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 Department 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 Department's website at: https://njstormwater.org/bmp_manual2.htm.
[Amended 2-23-2021 by Ord. No. 2021-01]
F.
Where the BMP tables in the NJ Stormwater Management
Rule are different due to updates or amendments with the tables in
this article, the BMP tables in the Stormwater Management rule at
N.J.A.C. 7:8-5.2(f) shall take precedence.
[Amended 2-23-2021 by Ord. No. 2021-01]
|
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)
1(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
|
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 Waiver or 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
|
N/A
|
|
Wet pond(d)
|
50-90
|
Yes
|
No
|
N/A
|
|
Table 3
BMPs for Groundwater Recharge, Stormwater Runoff Quality, and/or
Stormwater Runoff Quantity
only with a Waiver or 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
|
1
|
|
Manufactured treatment device(h)
|
50 or 80
|
No
|
No
|
Dependent upon the device
|
|
Sand filter(c)
|
80
|
Yes
|
No
|
1
|
|
Subsurface gravel wetland
|
90
|
No
|
No
|
1
|
|
Wet pond
|
50-90
|
Yes
|
No
|
N/A
|
|
Notes to Tables 1, 2, and 3:
| |
|---|---|
|
(a)
|
Subject to the applicable contributory drainage area limitation specified at § 262-4O(2).
|
|
(b)
|
Designed to infiltrate into the subsoil.
|
|
(c)
|
Designed with underdrains.
|
|
(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" in § 262-2.
|
|
(h)
|
Manufactured treatment devices that do not meet the definition of "green infrastructure" in § 262-2.
|
G.
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 Department in accordance with § 262-4B. Alternative stormwater management measures may be used to satisfy the requirements at § 262-4O only if the measures meet the definition of "green infrastructure" in § 262-2. Alternative stormwater management measures that function in a similar manner to a BMP listed at § 262-4O(2) are subject to the contributory drainage area limitation specified at § 262-4O(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 § 262-4O(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 N.J.A.C. 7:8-4.6 or a waiver from strict compliance in accordance with § 262-4D is granted from § 262-4O.
[Amended 2-23-2021 by Ord. No. 2021-01; 3-8-2022 by Ord. No. 2022-01]
H.
Whenever the stormwater management design includes one or more BMPs
that will infiltrate stormwater into subsoil, the design engineer
shall assess the hydraulic impact on the groundwater table and design
the site so as to avoid adverse hydraulic impacts. Potential adverse
hydraulic impacts include, but are not limited to, exacerbating a
naturally or seasonally high water table, so as to cause surficial
ponding, flooding of basements, or interference with the proper operation
of subsurface sewage disposal systems or other subsurface structures
within the zone of influence of the groundwater mound, or interference
with the proper functioning of the stormwater management measure itself.
[Added 2-23-2021 by Ord.
No. 2021-01]
I.
Design standards for stormwater management measures are as follows:
[Added 2-23-2021 by Ord.
No. 2021-01]
(1)
Stormwater management measures shall be designed to take into account
the existing site conditions, including, but not limited to, environmentally
critical areas; wetlands; 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 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. 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 § 262-8C;
(3)
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;
(4)
Stormwater management BMPs shall be designed to meet the minimum safety standards for stormwater management BMPs in § 262-8; and
(5)
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.
J.
Manufactured treatment devices may be used to meet the requirements of this article, provided the pollutant removal rates are verified by the New Jersey Corporation for Advanced Technology and certified by the Department. Manufactured treatment devices that do not meet the definition of "green infrastructure" in § 262-2 may be used only under the circumstances described in § 262-4O(4).
[Added 2-23-2021 by Ord.
No. 2021-01]
K.
Any application for a new agricultural development that meets the definition of "major development" in § 262-2 shall be submitted to the Soil Conservation District for review and approval in accordance with the requirements in § 262-4O through R 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.
[Added 2-23-2021 by Ord.
No. 2021-01; amended 3-8-2022 by Ord. No. 2022-01]
L.
If there is more than one drainage area, the groundwater recharge, stormwater runoff quality, and stormwater runoff quantity standards in § 262-4P through R shall be met in each drainage area, unless the runoff from the drainage areas converge 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.
[Added 2-23-2021 by Ord.
No. 2021-01; amended 3-8-2022 by Ord. No. 2022-01]
M.
Any stormwater management measure authorized under the municipal stormwater management plan or ordinance shall be reflected in a deed notice recorded in the Office of the Somerset County Clerk. 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 § 262-4O through R 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 § 262-10B(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.
[Added 2-23-2021 by Ord.
No. 2021-01; amended 3-8-2022 by Ord. No. 2022-01]
N.
A stormwater management measure approved under the municipal stormwater management plan or ordinance 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 pursuant to § 262-4 of this article 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 Office of the Somerset County Clerk and shall contain a description and location of the stormwater management measure, as well as reference to the maintenance plan, in accordance with Subsection M 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 M above.
[Added 2-23-2021 by Ord.
No. 2021-01; amended 3-8-2022 by Ord. No. 2022-01]
O.
Green infrastructure standards.
[Added 2-23-2021 by Ord.
No. 2021-01]
(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.
(2)
To satisfy the groundwater recharge and stormwater runoff quality standards in § 262-4P and Q, the design engineer shall utilize green infrastructure BMPs identified in Table 1 in § 262-4F and/or an alternative stormwater management measure approved in accordance with § 262-4G. 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 Systems
|
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
|
(3)
To satisfy the stormwater runoff quantity standards in § 262-4R, the design engineer shall utilize BMPs from Table 1 or from Table 2 and/or an alternative stormwater management measure approved in accordance with § 262-4-G.
(4)
If a variance in accordance with N.J.A.C. 7:8-4.6 or a waiver from strict compliance in accordance with § 262-4D is granted from the requirements of this subsection, then BMPs from Table 1, 2, or 3, and/or an alternative stormwater management measure approved in accordance with § 262-4G may be used to meet the groundwater recharge, stormwater runoff quality, and stormwater runoff quantity standards in § 262-4P, Q and R.
(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 in § 262-4P, Q, and R, unless the project is granted a waiver from strict compliance in accordance with § 262-4D.
P.
Groundwater recharge standards.
[Added 2-23-2021 by Ord.
No. 2021-01]
(1)
This subsection contains the minimum design and performance standards
for groundwater recharge as follows.
(2)
The design engineer shall, using the assumptions and factors for stormwater runoff and groundwater recharge calculations in § 262-5, either:
(a)
Demonstrate through hydrologic and hydraulic analysis that the
site and its stormwater management measures maintain 100% of the average
annual preconstruction groundwater recharge volume for the site; or
(b)
Demonstrate through hydrologic and hydraulic analysis that the
increase of stormwater runoff volume from preconstruction to post-construction
for the two-year storm is infiltrated.
(3)
This groundwater recharge requirement does not apply to projects within the urban redevelopment area, or to projects subject to Subsection P(4) below.
(4)
The following types of stormwater shall not be recharged:
(a)
Stormwater from areas of high pollutant loading. High pollutant
loading areas are 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 a Department-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;
and
(b)
Industrial stormwater exposed to source material. "Source material"
means 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.
Q.
Stormwater runoff quality standards.
[Added 2-23-2021 by Ord.
No. 2021-01]
(1)
This subsection contains the minimum design and performance standards
to control stormwater runoff quality impacts of major development.
Stormwater runoff quality standards are applicable when the major
development results in an increase of 1/4 acre or more of regulated
motor vehicle surface.
(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 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 an NJPDES permit from this requirement. Every major development, including any that discharge into a combined sewer system, shall comply with Subsection Q(2) above, unless the major development is itself subject to an 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
|
0.2000
|
85
|
1.1170
|
|
6
|
0.00996
|
46
|
0.2117
|
86
|
1.1236
|
|
7
|
0.01162
|
47
|
0.2233
|
87
|
1.1302
|
|
8
|
0.01328
|
48
|
0.2350
|
88
|
1.1368
|
|
9
|
0.01494
|
49
|
0.2466
|
89
|
1.1434
|
|
10
|
0.0166
|
50
|
0.2583
|
90
|
1.1500
|
|
11
|
0.01828
|
51
|
0.2783
|
91
|
1.1550
|
|
12
|
0.01996
|
52
|
0.2983
|
92
|
1.1600
|
|
13
|
0.02164
|
53
|
0.3183
|
93
|
1.1650
|
|
14
|
0.02332
|
54
|
0.3383
|
94
|
1.1700
|
|
15
|
0.02500
|
55
|
0.3583
|
95
|
1.1750
|
|
16
|
0.03000
|
56
|
0.4116
|
96
|
1.1800
|
|
17
|
0.03500
|
57
|
0.4650
|
97
|
1.1850
|
|
18
|
0.04000
|
58
|
0.5183
|
98
|
1.1900
|
|
19
|
0.04500
|
59
|
0.5717
|
99
|
1.1950
|
|
20
|
0.05000
|
60
|
0.6250
|
100
|
1.2000
|
|
21
|
0.05500
|
61
|
0.6783
|
101
|
1.2050
|
|
22
|
0.06000
|
62
|
0.7317
|
102
|
1.2100
|
|
23
|
0.06500
|
63
|
0.7850
|
103
|
1.2150
|
|
24
|
0.07000
|
64
|
0.8384
|
104
|
1.2200
|
|
25
|
0.07500
|
65
|
0.8917
|
105
|
1.2250
|
|
26
|
0.08000
|
66
|
0.9117
|
106
|
1.2267
|
|
27
|
0.08500
|
67
|
0.9317
|
107
|
1.2284
|
|
28
|
0.09000
|
68
|
0.9517
|
108
|
1.2300
|
|
29
|
0.09500
|
69
|
0.9717
|
109
|
1.2317
|
|
30
|
0.10000
|
70
|
0.9917
|
110
|
1.2334
|
|
31
|
0.10660
|
71
|
1.0034
|
111
|
1.2351
|
|
32
|
0.11320
|
72
|
1.0150
|
112
|
1.2367
|
|
33
|
0.11980
|
73
|
1.0267
|
113
|
1.2384
|
|
34
|
0.12640
|
74
|
1.0383
|
114
|
1.2400
|
|
35
|
0.13300
|
75
|
1.0500
|
115
|
1.2417
|
|
36
|
0.13960
|
76
|
1.0568
|
116
|
1.2434
|
|
37
|
0.14620
|
77
|
1.0636
|
117
|
1.2450
|
|
38
|
0.15280
|
78
|
1.0704
|
118
|
1.2467
|
|
39
|
0.15940
|
79
|
1.0772
|
119
|
1.2483
|
|
40
|
0.16600
|
80
|
1.0840
|
120
|
1.2500
|
(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. 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 § 262-4P, Q and R.
[Amended 3-8-2022 by Ord.
No. 2022-01]
(7)
In accordance with the definition of "FW1" at N.J.A.C. 7:9B-1.4,
stormwater management measures shall be designed to prevent any increase
in stormwater runoff to waters classified as FW1.
(8)
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.
(9)
Pursuant to the Flood Hazard Area Control Act Rules at N.J.A.C. 7:13-11.2(j)3i,
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.
(10)
These stormwater runoff quality standards do not apply to the
construction of one individual single-family dwelling, provided that
it is not part of a larger development or subdivision that has received
preliminary or final site plan approval prior to December 3, 2018,
and that the motor vehicle surfaces are made of permeable material(s)
such as gravel, dirt, and/or shells.
R.
Stormwater runoff quantity standards.
[Added 2-23-2021 by Ord.
No. 2021-01]
(1)
This subsection contains the minimum design and performance standards
to control stormwater runoff quantity impacts of major development.
(2)
In order to control stormwater runoff quantity impacts, the design engineer shall, using the assumptions and factors for stormwater runoff calculations at § 262-5, complete one of the following:
[Amended 3-8-2022 by Ord.
No. 2022-01]
(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 R(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.
A.
Stormwater runoff shall be calculated in accordance
with the following:
(1)
The design engineer shall calculate runoff using one
of the following methods:
[Amended 2-23-2021 by Ord. No. 2021-01]
(a)
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. 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 Davison Avenue, Somerset, New Jersey 08873; or
(b)
The Rational Method for peak flow and the Modified
Rational Method for hydrograph computations. The Rational and Modified
Rational methods are described in "Appendix A-9 Modified Rational
Method" in the Standards for Soil Erosion and Sediment Control in
New Jersey, January 2014. This document is available from the State
Soil Conservation Committee or any of the Soil Conservation Districts
listed at N.J.A.C. 2:90-1.3(a)3. The location, address, and telephone
number for each Soil Conservation District is available from the State
Soil Conservation Committee, PO Box 330, Trenton, New Jersey 08625.
The document is also available at: http://www.nj.gov/agriculture/divisions/anr/pdf/2014NJSoilErosionControlStandardsComplete.pdf.
(2)
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. The term "runoff coefficient" applies to both the NRCS methodology at § 262-5A(1)(a) and the Rational and Modified Rational Methods at § 262-5A(1)(b). 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 have 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).
(3)
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.
(4)
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, and other methods may be
employed.
(5)
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.
B.
Groundwater recharge may be calculated in accordance
with the following: the New Jersey Geological Survey Report GSR-32
A, Method for Evaluating Ground-Water 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, P.O.
Box 420, Mail Code 29-01, Trenton, New Jersey 08625-0420.
[Amended 2-23-2021 by Ord. No. 2021-01; 3-8-2022 by Ord. No. 2022-01]
[Amended 2-23-2021 by Ord. No. 2021-01[1]]
A.
Technical guidance for stormwater management measures can be found in the documents listed at Subsection A(1) and (2) below, which are available to download from the Department's website at: https://www.nj.gov/dep/stormwater/bmp_manual2.htm.
(1)
Guidelines for stormwater management measures are
contained in the New Jersey Stormwater Best Management Practices 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.
(2)
Additional maintenance guidance is available on the
Department's website at: https://www.njstormwater.org/maintenance_guidance.htm.
B.
Submissions required for review by the Department
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.
[Added 2-23-2021 by Ord. No. 2021-01[1]]
A.
Site design features identified under § 262-4F above, or alternative designs in accordance § 262-4G above, 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 § 262-7A(2) below.
(1)
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:
(a)
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
(b)
A different grate, if each individual clear space in that grate
has an area of no more than 7.0 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.
(c)
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 7.0 square inches, or be no greater than 2.0
inches across the smallest dimension.
(2)
The standard in Subsection A(1) above does not apply:
(a)
Where each individual clear space in the curb opening in the
existing curb-opening inlet does not have an area of more than 9.0
square inches;
(b)
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;
(c)
Where flows from the water quality design storm as specified
in N.J.A.C. 7:8 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:
[1]
A rectangular space 4.625 inches long and 1.5 inches wide (this
option does not apply for outfall netting facilities); or
[2]
A bar screen having a bar spacing of 0.5 inch.
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 5:21-7.4(b)1];
(d)
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 as specified in N.J.A.C. 7:8; or
(e)
Where the New Jersey Department of Environmental Protection
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.
[Amended 2-23-2021 by Ord. No. 2021-01]
A.
This section sets forth requirements to protect public
safety through the proper design and operation of stormwater management
basins. 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 § 262-8C(1) through (3) 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.
(d)
The trash rack shall be constructed and installed
to be rigid, durable and corrosion resistant and shall be 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, such grate shall meet 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 less
than two inches across the smallest dimension.
(c)
The overflow grate shall be constructed and
installed to be rigid, durable and corrosion resistant and shall be
designed to withstand a perpendicular live loading of 300 pounds per
square foot.
(3)
For purposes of this Subsection B(3), "escape provisions"
means the permanent installation of ladders, steps, rungs or other
features that provide easily accessible means of egress from stormwater
management basins. Stormwater management BMPs shall include escape
provisions as follows:
(a)
If a stormwater management basin has an outlet structure, escape provisions shall be incorporated in or on the structure. With the prior approval of the reviewing agency pursuant to § 262-8C, 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. Such 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 to one and one-half feet above the permanent water surface. See § 262-8E for an illustration of safety ledges in a stormwater management basin.
(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 standards. A variance
or exemption from the safety standards for stormwater management basins
may be granted only upon a written finding by the appropriate reviewing
agency (municipality, County or Department) that the variance or exemption
will not constitute a threat to public safety.
E.
Safety ledge illustration.
 |
A.
Submission of site development stormwater plan.
(1)
Whenever an applicant seeks municipal approval of
a development subject to this article, the applicant shall submit
all of the required components of the Checklist for the Site Development
Stormwater Plan at 262-9C below as part of the submission of the applicant's
application for subdivision or site plan approval.
(2)
The applicant shall demonstrate that the project meets
the standards set forth in this article.
B.
Site development stormwater plan approval. The applicant's
site development project shall be reviewed as a part of the subdivision
or site plan review process by the municipal board or official from
which 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 of the checklist requirements
have been satisfied and to determine if the project meets the standards
set forth in this article.
C.
Checklist requirements. The following information
shall be required:
(1)
Topographic base map. The reviewing engineer may require
upstream tributary drainage system information as necessary. It is
recommended that the topographic base map of the site be submitted
which extends a minimum of 200 feet beyond the limits of the proposed
development, at a scale of one inch equals 200 feet or greater, showing
two-foot contour intervals. The map as appropriate may indicate the
following: existing surface water drainage, shorelines, steep slopes,
soils, erodible soils, perennial or intermittent streams that drain
into or upstream of the Category One waters, wetlands and floodplains
along with their appropriate buffer strips, marshlands and other wetlands,
pervious or vegetative surfaces, existing man-made structures, roads,
bearing and distances of property lines and significant natural and
man-made features not otherwise shown.
(2)
Environmental site analysis. A written and graphic
description of the natural and man-made features of the site and its
environs. This description should include a discussion of soil conditions,
slopes, wetlands, waterways and vegetation on the site. Particular
attention should be given to unique, unusual or environmentally sensitive
features and to those that provide particular opportunities or constraints
for development.
(3)
Project description and site plan(s). A map (or maps)
at the scale of 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 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 of proposed
changes in natural conditions may also be provided.
(4)
Land use planning and source control plan. This plan shall provide a demonstration of how the goals and standards of §§ 262-3 through 262-6 are being met. The focus of this plan shall be to describe how the site is being developed to meet the objective of controlling groundwater recharge, stormwater quality and stormwater quantity problems at the source by land management and source controls whenever possible.
(5)
Stormwater management facilities map. The following
information, illustrated on a map of the same scale as the topographic
base map, shall be included:
(a)
Total area to be disturbed, paved 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 control and dispose of stormwater.
[Amended 3-8-2022 by Ord. No. 2022-01]
(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
and emergency spillway provisions with maximum discharge capacity
of each spillway.
(6)
Calculations.
(a)
Comprehensive hydrologic and hydraulic design calculations for the predevelopment and postdevelopment conditions for the design storms specified in § 262-4 of this article.
(b)
When the proposed stormwater management control
measures (e.g., infiltration basins) depends on the hydrologic properties
of soils, then a soils report shall be submitted. The soils report
shall be based on on-site boring logs or soil pit profiles. The number
and location of required soil borings or soil pits shall be determined
based on what is needed to determine the suitability and distribution
of soils present at the location of the control measure.
(7)
Maintenance and repair plan. The design and planning of the stormwater management facility shall meet the maintenance requirements of § 262-10.
(8)
Waiver from submission requirements. The municipal official or board reviewing an application under this article may, in consultation with the municipal engineer, waive submission of any of the requirements in § 262-9C(1) through (6) of this article when it can be demonstrated that the information requested is impossible to obtain or it would create a hardship on the applicant to obtain and its absence will not materially affect the review process.
B.
General maintenance.
[Amended 2-23-2021 by Ord. No. 2021-01]
(1)
The design engineer shall prepare a maintenance plan
for the stormwater management measures incorporated into the design
of a major development.
(2)
The maintenance plan shall contain 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.
(3)
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.
(4)
Responsibility for maintenance shall not be assigned
or transferred to the owner or tenant of an individual property in
a residential development or project unless such owner or tenant owns
or leases the entire residential development or project.
[Amended 3-8-2022 by Ord. No. 2022-01]
(5)
If the person responsible for maintenance identified under § 262-10B(3) above is not a public agency, the maintenance plan and any future revisions based on § 262-10B(7) below shall be recorded upon the deed of record for each property on which the maintenance described in the maintenance plan must be undertaken.
(6)
Preventative and corrective maintenance shall be performed
to maintain the functional parameters (storage volume, infiltration
rates, inflow/outflow capacity, etc.) of the stormwater management
measures, including 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.
(7)
The party responsible for maintenance identified under § 262-10B(3) above 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
(c)
Retain and make available, upon request by any public entity with administrative, health, environmental, or safety authority over the site, the maintenance plan and the documentation required by § 262-10B(6) and (7) above.
(8)
The requirements of § 262-10B(3) and (4) do not apply to stormwater management facilities that are dedicated to and accepted by the municipality or another governmental agency subject to all applicable municipal stormwater general permit conditions, as issued by the Department.
(9)
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.
C.
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.
D.
Maintenance of detention/retention/recharge basins.
[Added 2-22-2011 by Ord.
No. 2011-04; amended 11-22-2011 by Ord. No. 2011-19]
(1)
All detention/retention basins for stormwater drainage, and recharge
basins for water quality, also known as stormwater facilities:
(a)
In any multifamily residential development or nonresidential
development, shall be owned and maintained by a condominium homeowners'
association or other private entity; and
(b)
In or as a part of a solely single-family residential development,
shall be:
[1]
Owned and maintained by a homeowners' association or other private
entity, until and unless specifically accepted by the Township of
Hillsborough for compelling reasons of public health, safety or welfare;
and
[2]
Situated on a lot or lots that are separate from any lots that
contain single-family dwellings.
(2)
Prior to the issuance to a developer of any certificate of occupancy
and prior to the acceptance by the Township of any existing basin,
for compelling reasons of public health, safety, and welfare, from
a homeowners' association or other private entity:
(a)
The stormwater facility shall be certified by the Township Engineer
to have been constructed in accordance with the requirements and specifications
of this section, with any deficiencies thus noted to be corrected
by the developer, homeowners' association or other private entity
currently holding ownership; and
(b)
The developer or homeowners' association or other private entity
currently holding ownership shall post with the Township of Hillsborough
an amount to be determined in accordance with the formula set forth
below, for maintenance of said basin for 25 years, to be placed in
an escrow account, which funds shall be utilized for the maintenance
of such detention/retention/recharge basin.
(3)
Prior to the issuance to a developer of any certificate of occupancy
and where a homeowners' association or other private entity is to
assume maintenance responsibilities for a detention/retention/recharge
basin:
(a)
The stormwater facility shall be certified by the Township Engineer
to have been constructed in accordance with the requirements and specifications
of this section, with any deficiencies thus noted to be corrected
by the developer, homeowners' association or other private entity
currently holding ownership; and
(b)
The developer shall post with the homeowners' association or
other private entity, as appropriate, an amount to be determined in
accordance with the formula set forth below, for the maintenance of
said basin for 25 years; and
(c)
The amount deposited shall be dedicated solely for the uses
and purpose described in this subsection.
(4)
Maintenance fees:
(a)
The fees required by Schedule A, as set forth below,[1] shall be for the purpose of reimbursing the Township or
homeowners' association or other private entity, as appropriate, for
direct fees, costs, charges and expenses for the maintenance of a
detention/retention facility, including, but not limited to, routine
mowing, maintenance of landscaping, general maintenance concerning
inlets, cleaning of property and long-range maintenance on a periodic
basis.
[1]
Editor's Note: Schedule A is included as an attachment to this chapter.
(b)
The amount required in Schedule A shall be deposited with the
Township or homeowners' association or other private entity, as appropriate,
prior to the issuance of any certificates of occupancy. All funds
shall remain in an interest-bearing escrow account. The entire amount
of any interest shall be applied to the purposes for which it was
originally deposited.
(c)
All costs, expenses, charges and fees incurred by the Township
or homeowners' association or other private entity, as appropriate,
for the maintenance of a detention/retention basin, shall be charged
against the escrow fund established for the maintenance of such a
basin.
(d)
The Township or homeowners' association or other private entity,
as appropriate, will conduct maintenance programs at its discretion
and shall maintain liability insurance on the basin out of the funds
so created. The maintenance programs are based on Township labor and
equipment costs and may include:
[1]
Routine mowing of the detention/retention/recharge basin. Mowing
costs shall be estimated at the rate of one acre per hour. The cost
per hour for the Township labor and equipment shall be multiplied
by the number of acres to be mowed. A base number shall also be included
for the mobilization and maintenance of the equipment.
[2]
Maintenance of landscaping of detention/retention/recharge basins.
The cost shall be based upon the number of hours for landscape maintenance
multiplied by a rate per hour of labor and equipment. Any and all
additional stock which shall be necessary to replace approved landscaping
shall also be charged against the fund.
[3]
General maintenance of detention/retention/recharge basins.
The cost for general maintenance shall be based upon a one-hour mobilization
time together with the total number of hours expended times the rate
per hour for Township labor and equipment.
[4]
Long-term maintenance of detention/retention/recharge basins.
The long-term maintenance shall be calculated on a cost per acre and
applied against the assumption that a residential detention/retention
basin needs rejuvenation every 15 years. These amounts are reduced
thereto an annualized cost.
[5]
Insurance of detention/retention/recharge basins. The Township
or homeowners' association or other private entity, as appropriate,
shall assume liability for the property, and a portion of the fund
shall be used for purchase of insurance for the detention/retention
basin.
(e)
Calculation of the maintenance fund of detention/retention/recharge
basins. The amount of money to be placed in escrow shall be calculated
in accordance with the worksheet set forth in Schedule A. The first-year
costs are multiplied by the factor of 26.48. Said calculation provides
for the Township or homeowners' association or other private entity,
as appropriate, to receive sufficient funding for 25 years based upon
an assumption of a six-percent increase per year and one-half percent
return on investment earnings added to the account. The cost for the
maintenance by the Township employees shall be based upon the amount
of time services are performed and the unit (i.e., per diem or hourly
fee) of the professional, expert, employee or staff member in accordance
with the contracts or as prescribed by the salary ordinance of the
Township of Hillsborough.
Any person who erects, constructs, alters, repairs,
converts, maintains or uses any building, structure or land in violation
of this article shall be subject to the following penalties: imprisonment
in the Somerset County Jail or in any place provided by the Township
of the detention of prisoners, for any term not exceeding 90 days;
or by a fine not exceeding $1,250; or by a period of community service
not exceeding 90 days.
This article shall take effect immediately upon
the approval by the County review agency or 60 days from the receipt
of the ordinance by the County review agency if the County review
agency should fail to act.
If the provisions of any section, subsection,
paragraph, subdivision or clause of this article shall be judged invalid
by a court of competent jurisdiction, such order of judgment shall
not affect or invalidate the remainder of any section, subsection,
paragraph, subdivision or clause of this article.
