The development shall incorporate a maintenance plan for the stormwater management measures incorporated into the design of a major development in accordance with Article XX.
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 muhlenbergi
(bog turtle).
The following linear development projects are exempt from the groundwater recharge, stormwater runoff quantity, and stormwater runoff quality requirements of §§ 330-53 and 330-54:
A.
The construction of an underground utility line, provided that the
disturbed areas are revegetated upon completion;
B.
The construction of an aboveground utility line, provided that the
existing conditions are maintained to the maximum extent practicable;
and
C.
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.
A waiver from strict compliance from the groundwater recharge, stormwater runoff quantity, and stormwater runoff quality requirements of §§ 330-53 and 330-54 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 § 330-51C above within the upstream drainage area of the receiving stream, that would provide additional opportunities to mitigate the requirements of §§ 330-53 and 330-54 that were not achievable on site.
A.
To the maximum extent practicable, the standards in §§ 330-53 and 330-54 shall be met by incorporating nonstructural stormwater management strategies set forth at § 330-52 into the design. The applicant shall identify the nonstructural measures incorporated into the design of the project. If the applicant contends that it is not feasible for engineering, environmental, or safety reasons to incorporate any nonstructural stormwater management measures identified in § 330-52B below into the design of a particular project, the applicant shall identify the strategy considered and provide a basis for the contention.
B.
Nonstructural stormwater management strategies incorporated into
site design shall:
(1)
Protect areas that provide water quality benefits or areas particularly
susceptible to erosion and sediment loss;
(2)
Minimize impervious surfaces and break up or disconnect the flow
of runoff over impervious surfaces;
(3)
Maximize the protection of natural drainage features and vegetation;
(4)
Minimize the decrease in the time of concentration from preconstruction
to post-construction. "Time of concentration" is defined as the time
it takes for runoff to travel from the hydraulically most distant
point of the watershed to the point of interest within a watershed;
(5)
Minimize land disturbance, including clearing and grading;
(6)
Minimize soil compaction;
(7)
Provide low-maintenance landscaping that encourages retention and
planting of native vegetation and minimizes the use of lawns, fertilizers
and pesticides;
(8)
Provide vegetated open-channel conveyance systems discharging into
and through stable vegetated areas;
(9)
Provide other source controls to prevent or minimize the use or exposure
of pollutants at the site, in order to prevent or minimize the release
of those pollutants into stormwater runoff. Such source controls include,
but are not limited to:
(a)
Site design features that help to prevent accumulation of trash and debris in drainage systems, including features that satisfy § 330-52C below;
(b)
Site design features that help to prevent discharge of trash
and debris from drainage systems;
(c)
Site design features that help to prevent and/or contain spills
or other harmful accumulations of pollutants at industrial or commercial
developments; and
(d)
When establishing vegetation after land disturbance, applying
fertilizer in accordance with the requirements established under the
Soil Erosion and Sediment Control Act, N.J.S.A. 4:24-39 et seq., and
implementing rules.
C.
Site design features identified under § 330-52B(9)(a) above shall comply with the following standard to control passage of solid and floatable materials through storm drain inlets. For purposes of this subsection, "solid and floatable materials" means sediment, debris, trash, and other floating, suspended, or settleable solids. For exemptions to this standard see § 330-52C(3) below.
(1)
Grates.
(a)
Design engineers shall use either 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 (April 1996);
or
[2]
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.
(b)
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 basin floors.
(2)
Whenever design engineers use a curb-opening inlet, 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.
(3)
This standard does not apply:
(a)
Where the review agency determines that this standard would
cause inadequate hydraulic performance that could not practicably
be overcome by using additional or larger storm drain inlets that
meet these standards;
(b)
Where flows from the water quality design storm as specified in § 330-54A 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:
(c)
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 § 330-54A; or
(d)
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.
D.
Any land area used as a nonstructural stormwater management measure to meet the performance standards in §§ 330-53 and 330-54 shall be dedicated to a government agency, subjected to a conservation restriction filed with the appropriate County Clerk's office, or subject to an approved equivalent restriction that ensures that measure or an equivalent stormwater management measure approved by the reviewing agency is maintained in perpetuity.
A.
This subsection contains minimum design and performance standards
to control erosion, encourage and control infiltration and groundwater
recharge, and control stormwater runoff quantity impacts of major
development.
(1)
The minimum design and performance 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.
(2)
The minimum design and performance standards for groundwater recharge
are as follows:
(a)
The design engineer shall, using the assumptions and factors for stormwater runoff and groundwater recharge calculations at Article XV, either:
[1]
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
[2]
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.
(b)
This groundwater recharge requirement does not apply to projects within the urban redevelopment area, or to projects subject to § 330-53A(2)(c) below.
(c)
The following types of stormwater shall not be recharged:
[1]
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 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
[2]
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.
(d)
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 and
other subsurface structures in the vicinity or downgradient of the
groundwater recharge area.
(3)
In order to control stormwater runoff quantity impacts, the design engineer shall, using the assumptions and factors for stormwater runoff calculations at Article XV 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 one-hundred-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 one-hundred-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 one-hundred-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. The percentages
shall not be applied to post-construction stormwater runoff into tidal
flood hazard areas if the increased volume of stormwater runoff will
not increase flood damages below the point of discharge; or
(d)
In tidal flood hazard areas, stormwater runoff quantity analysis in accordance with § 330-53A(3)(a), (b) and (c) above shall only be applied if the increased volume of stormwater runoff could increase flood damages below the point of discharge.
B.
Any application for a new agricultural development that meets the definition of "major development" at Article XII shall be submitted to the appropriate Soil Conservation District for review and approval in accordance with the requirements of this section and any applicable Soil Conservation District guidelines for stormwater runoff quantity and erosion control. For the purposes of this section, "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 manufacturing of agriculturally related products.
A.
Stormwater management measures shall be designed to reduce the post-construction
load of total suspended solids (TSS) in stormwater runoff by 80% of
the anticipated load from the developed site, expressed as an annual
average. Stormwater management measures shall only be required for
water quality control if an additional 1/4 acre of impervious surface
is being proposed on a development site. 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 Pollution Discharge Elimination System (NJPDES) rules, N.J.A.C.
7:14A, or in a discharge specifically exempt under a NJPDES permit
from this requirement. 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 1. The calculation of the volume of runoff may
take into account the implementation of nonstructural and structural
stormwater management measures.
|
Table 1
Water Quality Design Storm Distribution1
| |||
|---|---|---|---|
|
Time
(minutes)
|
Cumulative Rainfall
(inches)
|
Time
(minutes)
|
Cumulative Rainfall
(inches)
|
|
0
|
0.0000
|
65
|
0.8917
|
|
5
|
0.0083
|
70
|
0.9917
|
|
10
|
0.0166
|
75
|
1.0500
|
|
15
|
0.0250
|
80
|
1.0840
|
|
20
|
0.0500
|
85
|
1.1170
|
|
25
|
0.0750
|
90
|
1.1500
|
|
30
|
0.1000
|
95
|
1.1750
|
|
35
|
0.1330
|
100
|
1.2000
|
|
40
|
0.1660
|
105
|
1.2250
|
|
45
|
0.2000
|
110
|
1.2334
|
|
50
|
0.2583
|
115
|
1.2417
|
|
55
|
0.3583
|
120
|
1.2500
|
|
60
|
0.6250
| ||
B.
For purposes of TSS reduction calculations, Table 2 below presents the presumed removal rates for certain BMPs designed in accordance with the New Jersey Stormwater Best Management Practices Manual. The BMP Manual may be obtained from the address identified in Article XVII, or found on the Department's website at www.njstormwater.org. The BMP Manual and other sources of technical guidance are listed in Article XVII. TSS reduction shall be calculated based on the removal rates for the BMPs in Table 2 below. Alternative removal rates and methods of calculating removal rates may be used if the design engineer provides documentation demonstrating the capability of these alternative rates and methods to the review agency. A copy of any approved alternative rate or method of calculating the removal rate shall be provided to the Department at the following address: Division of Watershed Management, New Jersey Department of Environmental Protection, P.O. Box 418, Trenton, New Jersey 08625-0418.
C.
If more than one BMP in series is necessary to achieve the required
TSS reduction of 80% for a site, the applicant shall utilize the following
formula to calculate TSS reduction:
|
R = A + B - (AXB)/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.
| |
|
Table 2: TSS Removal Rates for BMPs
| |
|---|---|
|
Best Management Practice
|
TSS Percent Removal Rate
|
|
Bioretention systems
|
90%
|
|
Constructed stormwater wetland
|
90%
|
|
Extended detention basin
|
40% to 60%
|
|
Infiltration structure
|
80%
|
|
Manufactured treatment device
|
See § 330-59.
|
|
Sand filter
|
80%
|
|
Vegetative filter strip
|
60% to 80%
|
|
Wet pond
|
50% to 90%
|
D.
If there is more than one on-site drainage area, the eighty-percent
TSS removal rate shall apply to each drainage area, unless the runoff
from the subareas coverage on site, in which case the removal rate
can be demonstrated through a calculation using a weighted average.
E.
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 nonstructural strategies and structural measures that optimize nutrient removal while still achieving the performance standards in §§ 330-53 and 330-54.
F.
Additional information and examples are contained in the New Jersey Stormwater Best Management Practices Manual, which may be obtained from the address identified in Article XVII.
G.
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.
H.
Special water resource protection areas shall be established along
all waters designated Category One at N.J.A.C. 7:9B, and perennial
or intermittent streams that drain into or upstream of the Category
One waters as shown on the USGS Quadrangle Maps or in the County Soil
Surveys, within the associated HUC14 drainage area. These areas shall
be established for the protection of water quality, aesthetic value,
exceptional ecological significance, exceptional recreational significance,
exceptional water supply significance, and exceptional fisheries significance
of those established Category One waters. These areas shall be designated
and protected as follows:
(1)
The applicant shall preserve and maintain a special water resource
protection area in accordance with one of the following:
(a)
A three-hundred-foot special water resource protection area
shall be provided on each side of the waterway, measured perpendicular
to the waterway from the top of the bank outwards or from the center
line of the waterway where the bank is not defined, consisting of
existing vegetation or vegetation allowed to follow natural succession
is provided.
(b)
Encroachment within the designated special water resource protection area under § 330-54H(1)(a) above shall only be allowed where previous development or disturbance has occurred (for example, active agricultural use, parking area or maintained lawn area). The encroachment shall only be allowed where the applicant demonstrates that the functional value and overall condition of the special water resource protection area will be maintained to the maximum extent practicable. In no case shall the remaining special water resource protection area be reduced to less than 150 feet as measured perpendicular to the top of bank of the waterway or center line of the waterway where the bank is undefined. All encroachments proposed under this subsection shall be subject to review and approval by the Department.
(2)
All stormwater shall be discharged outside of and flow through the
special water resource protection area and shall comply with the standard
for off-site stability in the Standards For Soil Erosion and Sediment
Control in New Jersey, established under the Soil Erosion and Sediment
Control Act, N.J.S.A. 4:24-39 et seq.
(3)
If stormwater discharged outside of and flowing through the special
water resource protection area cannot comply with the standard for
off-site stability in the Standards for Soil Erosion and Sediment
Control in New Jersey, established under the Soil Erosion and Sediment
Control Act, N.J.S.A. 4:24-39 et seq., then the stabilization measures
in accordance with the requirements of the above standards may be
placed within the special water resource protection area, provided
that:
(a)
Stabilization measures shall not be placed within 150 feet of
the Category One waterway;
(b)
Stormwater associated with discharges allowed by this section
shall achieve a TSS post-construction removal rate of 95%;
(c)
Temperature shall be addressed to ensure no impact on the receiving
waterway;
(d)
The encroachment shall only be allowed where the applicant demonstrates
that the functional value and overall condition of the special water
resource protection area will be maintained to the maximum extent
practicable;
(e)
A conceptual project design meeting shall be held with the appropriate
Department staff and Soil Conservation District staff to identify
necessary stabilization measures; and
(f)
All encroachments proposed under this section shall be subject
to review and approval by the Department.
(4)
A stream corridor protection plan may be developed by a regional stormwater management planning committee as an element of a regional stormwater management plan, or by a municipality through an adopted municipal stormwater management plan. If a stream corridor protection plan for a waterway subject to § 330-54H has been approved by the Department of Environmental Protection, then the provisions of the plan shall be the applicable special water resource protection area requirements for that waterway. A stream corridor protection plan for a waterway subject to § 330-54H shall maintain or enhance the current functional value and overall condition of the special water resource protection area as defined in § 330-54H(1)(a) above. In no case shall a stream corridor protection plan allow the reduction of the special water resource protection area to less than 150 feet as measured perpendicular to the waterway subject to this subsection.
