ORDINANCE NO. 06-06
AN ORDINANCE TO amend
Section 310-102C REPLACE SECTION 310-107 OF THE CODE OF THE BOROUGH OF
HILLSDALE TO PROVIDE COMPREHENSIVE REGULATION OF STORM WATER MANAGEMENT FOR
THE BOROUGH OF HILLSDALE,COUNTY OF
BERGEN, STATE OF NEW JERSEY
WHEREAS, the State of New Jersey has required the re-adoption of storm water
management regulations, and
WHEREAS, Hillsdale’s
Ordinances require amendment to comply;
NOW THEREFORE BE IT ORDAINED, by the Borough Council
of the Borough of Hillsdale in the County of Bergen and State of New Jersey as
follows:
I. Subsection 310-102. Utilities design standards, inspections and approvals, of the Land Use Section of the Code of the Borough of Hillsdale is supplemented
to add Section 310-102C as follows:
C. All requirements
contained in Section 310-107 shall be followed and included as part of the Subdivision Design Standards.”
II. Subsection 310-107 Drainage of
the Land Use Section of the Code of the Borough of
Hillsdale is replaced as follows:
§ 310-107 Stormwater Management
Section
1: Definitions
Unless
specifically defined below, words or phrases used in this ordinance shall be
interpreted so as to give them the meaning they have in common usage and to
give this ordinance its most reasonable application. 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.
“CAFRA Planning Map”
means the geographic depiction of the boundaries for Coastal Planning Areas,
CAFRA Centers, CAFRA Cores and CAFRA Nodes pursuant to N.J.A.C. 7:7E-5B.3.
“CAFRA Centers, Cores or
Nodes” means those areas within boundaries accepted by the New Jersey
Department of Environmental Protection (the Department) pursuant to N.J.A.C.
7:8E-5B.
“Compaction” means the
increase in soil bulk density.
“Core” means a
pedestrian-oriented area of commercial and civic uses serving the surrounding
municipality, generally including housing and access to public transportation.
“County review agency”
means an agency designated by the County Board of Chosen Freeholders to review
municipal stormwater management plans and implementing ordinance(s). The county
review agency may either be:
A
county planning agency; or
A
county water resource association created under N.J.S.A 58:16A-55.5, if the
ordinance or resolution delegates authority to approve, conditionally approve,
or disapprove municipal stormwater management plans and implementing
ordinances.
“Department”
means the New Jersey Department of Environmental Protection.
“Designated Center,”
means a State Development and Redevelopment Plan Center as designated by the
State Planning Commission such as urban, regional, town, village, or hamlet.
“Design engineer” means
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.
“Development” means 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, by any person, 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.
“Drainage area” means a
geographic area within which stormwater, sediments, or dissolved materials
drain to a particular receiving waterbody or to a particular point along a
receiving waterbody.
“Environmentally
critical areas” means 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 well head 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.
“Empowerment
Neighborhood” means a neighborhood designated by the Urban Coordinating Council
“in consultation and conjunction with” the New Jersey Redevelopment Authority
pursuant to N.J.S.A 55:19-69.
“Erosion” means the
detachment and movement of soil or rock fragments by water, wind, ice or
gravity.
“Impervious surface”
means a surface that has been covered with a layer of material so that it is
highly resistant to infiltration by water.
This definition is for the purpose of this Stormwater Management
Ordinance only.
“Infiltration” is the
process by which water seeps into the soil from precipitation.
“Major development”
means any “development” that provides for ultimately disturbing one or more
acres of land. Disturbance for the purpose of this rule is the placement of
impervious surface or exposure and/or movement of soil or bedrock or clearing,
cutting, or removing of vegetation.
“Municipality” means any
city, borough, town, township, or village.
“Node” means an area
designated by the State Planning Commission concentrating facilities and
activities that are not organized in a compact form.
“Nutrient” means a
chemical element or compound, such as nitrogen or phosphorus, which is
essential to and promotes the development of organisms.
“Person” means any
individual, corporation, company, partnership, firm, association, Borough of
Hillsdale, or political subdivision of this State subject to municipal
jurisdiction pursuant to the Municipal Land Use Law, N.J.S.A. 40:55D-1 et seq.
“Pollutant” means 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, ground waters or surface
waters of the State, or to a domestic treatment works. “Pollutant” includes
both hazardous and nonhazardous pollutants.
“Recharge” means the
amount of water from precipitation that infiltrates into the ground and is not
evapotranspired.
“Sediment” means 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.
“Site” means the lot or
lots upon which a major development is to occur or has occurred.
“Soil” means all
unconsolidated mineral and organic material of any origin.
“State Development and
Redevelopment Plan Metropolitan Planning Area (PA1)” means 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.
“State Plan Policy Map”
is defined as the geographic application of the State Development and
Redevelopment Plan’s goals and statewide policies, and the official map of
these goals and policies.
“Stormwater” means 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.
“Stormwater runoff”
means water flow on the surface of the ground or in storm sewers, resulting
from precipitation.
“Stormwater management
basin” means 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).
“Stormwater management
measure” means 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
non-stormwater discharges into stormwater conveyances.
“Tidal Flood Hazard
Area” means a flood hazard area, which may be influenced by stormwater runoff
from inland areas, but which is primarily caused by the Atlantic Ocean.
“Urban Coordinating
Council Empowerment Neighborhood” means a neighborhood given priority access to
State resources through the New Jersey Redevelopment Authority.
“Urban Enterprise Zones”
means 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.
“Urban Redevelopment
Area” is defined as previously developed portions of areas:
(1) Delineated
on the State Plan Policy Map (SPPM) as the Metropolitan Planning Area (PA1),
Designated Centers, Cores or Nodes;
(2) Designated
as CAFRA Centers, Cores or Nodes;
(3) Designated
as Urban Enterprise Zones; and
(4) Designated
as Urban Coordinating Council Empowerment Neighborhoods.
“Waters of the State” means
the ocean and its estuaries, all springs, streams, wetlands, and bodies of
surface or ground water, whether natural or artificial, within the boundaries
of the State of New Jersey or subject to its jurisdiction.
“Wetlands” or “wetland”
means an area that is inundated or saturated by surface water or ground water
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.
Section
2: Scope and Purpose
A.
Policy Statement
Flood control, groundwater recharge, and
pollutant reduction through nonstructural or low impact techniques shall be
explored before relying on structural Best Management Practices (BMPs).
Structural BMPs shall be integrated with nonstructural stormwater management
strategies and proper maintenance plans. Nonstructural strategies include both
environmentally sensitive site design and source controls that prevent
pollutants from being placed on the site or from being exposed to stormwater.
Source control plans shall 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.
B.
Purpose
It is the purpose of this ordinance to establish
minimum stormwater management requirements and controls for “major
development,” as defined in Section 1.
C.
Applicability
1. This ordinance shall be applicable to all
site plans and subdivisions for the following major developments that require
preliminary or final site plan or subdivision review:
a.
Non-residential
major developments; and
b.
Aspects
of residential major developments that are not pre-empted by the Residential
Site Improvement Standards at N.J.A.C. 5:21.
2. This ordinance shall also be applicable to
all major developments undertaken by the Borough of Hillsdale.
D. Compatibility with Other Permit and Ordinance
Requirements
Development approvals issued for subdivisions
and site plans pursuant to this ordinance are to be considered an integral part
of development approvals under the subdivision and site plan review process 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
ordinance shall be held to be the minimum requirements for the promotion of the
public health, safety, and general welfare. This ordinance 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
ordinance 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.
Section 3: General Standards
A.
Design and Performance Standards for Stormwater Management Measures
1. Stormwater management measures for major
development shall be developed to meet the erosion control, groundwater
recharge, stormwater runoff quantity, and stormwater runoff quality standards
in Section 4. To the maximum extent practicable, these standards shall be met
by incorporating nonstructural stormwater management strategies into the
design. If these strategies alone are not sufficient to meet these standards,
structural stormwater management measures necessary to meet these standards
shall be incorporated into the design.
2.
The
standards in this ordinance 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.
3.
Alternative standards shall provide at least as
much protection from stormwater-related loss of groundwater recharge,
stormwater quantity and water quality impacts of major development projects as
would be provided under the standards in N.J.A.C. 7:8-5.
Section
4: Stormwater Management Requirements for Major Development
A.
The development shall incorporate a maintenance plan for the stormwater
management measures incorporated into the design of a major development in
accordance with Section 10.
B.
Stormwater management measures shall avoid adverse impacts of concentrated flow
on habitat for threatened and endangered species as documented in the
Department’ Landscape Project or Natural Heritage Database established under
N.J.S.A. 13:1B-15.147 through 15.150, particularly Helonias bullata (swamp pink) and/or Clemmys muhlnebergi (bog turtle).
C.
The following linear development projects are exempt from the groundwater
recharge, stormwater runoff quantity, and stormwater runoff quality
requirements of Sections 4.F and 4.G:
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.
A waiver from strict compliance from the groundwater recharge, stormwater
runoff quantity, and stormwater runoff quality requirements of Sections 4.F and
4.G 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:
1. The applicant demonstrates that there is a
public need for the project that cannot be accomplished by any other means;
2. The applicant demonstrates through an
alternatives analysis, that through the use of nonstructural and structural
stormwater management strategies and measures, the option selected complies
with the requirements of Sections 4.F and 4.G to the maximum extent
practicable;
3. The applicant demonstrates that, in order to
meet the requirements of Sections 4.F and 4.G, existing structures currently in
use, such as homes and buildings, would need to be condemned; and
4.
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
D.3 above within the upstream drainage area of the receiving stream, that would
provide additional opportunities to mitigate the requirements of Sections 4.F and
4.G that were not achievable on-site.
E.
Nonstructural Stormwater Management Strategies
1.
To the maximum extent practicable, the standards in Sections 4.F and 4.G shall
be met by incorporating nonstructural stormwater management strategies set
forth at Section 4.E 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 Paragraph 2 below into the design of a particular project, the
applicant shall identify the strategy considered and provide a basis for the
contention.
2. Nonstructural stormwater management strategies
incorporated into site design shall:
a.
Protect areas that provide water quality benefits or areas particularly
susceptible to erosion and sediment loss;
b.
Minimize impervious surfaces and break up or disconnect the flow of runoff over
impervious surfaces;
c.
Maximize the protection of natural drainage features and vegetation;
d.
Minimize the decrease in the "time of concentration” from pre-construction
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;
e. Minimize land disturbance including clearing
and grading;
f. Minimize soil compaction;
g.
Provide low-maintenance landscaping that encourages retention and planting of
native vegetation and minimizes the use of lawns, fertilizers and pesticides;
h.
Provide vegetated open-channel conveyance systems discharging into and through
stable vegetated areas;
i. 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:
(1) Site design features that help to prevent
accumulation of trash and debris in drainage systems, including features that
satisfy Section 4.E.3. below;
(2) Site design features that help to prevent
discharge of trash and debris from drainage systems;
(3) Site design features
that help to prevent and/or contain spills or other harmful accumulations of
pollutants at industrial or commercial developments; and
(4) 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.
3. Site design features identified under Section
4.E.2.i.(2) above shall comply with the following standard to control passage
of solid and floatable materials through storm drain inlets. For purposes of
this paragraph, “solid and floatable materials” means sediment, debris, trash,
and other floating, suspended, or settleable solids. For exemptions to this
standard see Section 4.E.3.c below.
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 seven (7.0) square inches, or
is no greater than 0.5 inches 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 basin floors.
b. 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 seven (7.0) square inches, or be no greater than two (2.0) inches across the
smallest dimension.
c. This standard does not apply:
(1) 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;
(2) Where flows from the water quality design
storm as specified in Section 4.G.1 are conveyed through any device (e.g., end
of pipe netting facility, manufactured treatment device, or a catch basin hood)
that is designed, at a minimum, to prevent delivery of all solid and floatable
materials that could not pass through one of the following:
(a) A rectangular space four and five-eighths
inches long and one and one-half inches wide (this option does not apply for
outfall netting facilities); or
(b) A bar screen having a bar spacing of 0.5
inches.
(3) Where flows are conveyed through a trash rack
that has parallel bars with one-inch (1”) spacing between the bars, to the
elevation of the water quality design storm as specified in Section 4.G.1; or
(4) 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.
4.
Any land area used as a nonstructural stormwater management measure to meet the
performance standards in Sections 4.F and 4.G 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.
5. Guidance for nonstructural stormwater
management strategies is available in the New Jersey Stormwater Best Management
Practices Manual. The BMP Manual may be obtained from the Department.
F.
Erosion Control, Groundwater Recharge and Runoff Quantity Standards
1. 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.
a. 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.
b. The minimum design and performance standards
for groundwater recharge are as follows:
(1) The design engineer shall, using the
assumptions and factors for stormwater runoff and groundwater recharge
calculations at Section 5, either:
(a) Demonstrate through hydrologic and hydraulic
analysis that the site and its stormwater management measures maintain 100
percent of the average annual pre-construction groundwater recharge volume for
the site; or
(b) Demonstrate through hydrologic and hydraulic
analysis that the increase of stormwater runoff volume from pre-construction to
post-construction for the 2-year storm is infiltrated.
(2) This groundwater recharge requirement does not
apply to projects within the “urban redevelopment area,” or to projects subject
to (3) below.
(3) 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 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.
(4) 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.
c. In order to control stormwater runoff quantity
impacts, the design engineer shall, using the assumptions and factors for
stormwater runoff calculations at Section 5, complete one of the following:
(1) Demonstrate through hydrologic and hydraulic
analysis that for stormwater leaving the site, post-construction runoff
hydrographs for the two, 10, and 100-year storm events do not exceed, at any
point in time, the pre-construction runoff hydrographs for the same storm events;
(2) Demonstrate through hydrologic and hydraulic
analysis that there is no increase, as compared to the pre-construction
condition, in the peak runoff rates of stormwater leaving the site for the two,
10, 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;
(3) Design
stormwater management measures so that the post-construction peak runoff rates
for the 2, 10 and 100 year storm events are 50, 75 and 80 percent,
respectively, of the pre-construction 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
(4) In tidal flood hazard areas, stormwater runoff
quantity analysis in accordance with (1), (2) and (3) above shall only be
applied if the increased volume of stormwater runoff could increase flood
damages below the point of discharge.
2. Any application for a new agricultural
development that meets the definition of major development at Section 1 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.
G.
Stormwater Runoff Quality Standards
1. Stormwater
management measures shall be designed to reduce the post-construction load of
total suspended solids (TSS) in stormwater runoff by 80 percent 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 non-structural and structural stormwater
management measures.
Table
1: Water Quality Design Storm Distribution |
|||
|
Time
|
Cumulative
|
Time
|
Cumulative
|
|
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 |
|
|
2. 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 Section 7, or found
on the Department’s website at www.njstormwater.org.
The BMP Manual and other sources of technical guidance are listed in Section 7.
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, PO Box
418 Trenton, New Jersey, 08625-0418.
3. If more than one BMP in series is necessary to
achieve the required 80 percent TSS reduction 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, and
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 |
40-60 |
|
Infiltration Structure |
80 |
|
Manufactured Treatment Device |
See Section 6.C |
|
Sand Filter |
80 |
|
Vegetative Filter Strip |
60-80 |
|
Wet Pond |
50-90 |
4. If there
is more than one onsite drainage area, the 80 percent TSS removal rate shall
apply to each drainage area, unless the runoff from the subareas converge on
site in which case the removal rate can be demonstrated through a calculation
using a weighted average.
5. 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 Sections 4.F and 4.G.
6. Additional information and examples are
contained in the New Jersey Stormwater Best Management Practices Manual, which
may be obtained from the address identified in Section 7.
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. 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:
a.
The applicant shall preserve and maintain a special water resource protection
area in accordance with one of the following:
(1) A
300-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 centerline of the waterway where the bank is not
defined, consisting of existing vegetation or vegetation allowed to follow
natural succession is provided. (2) Encroachment
within the designated special water resource protection area under Subsection
(1) 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 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 centerline of the waterway where the bank is undefined. All encroachments
proposed under this subparagraph shall be subject to review and approval by the
Department.
b. 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.
c. 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:
(1) Stabilization measures shall not be placed
within 150 feet of the Category One waterway;
(2) Stormwater associated with discharges allowed
by this section shall achieve a 95 percent TSS post-construction removal rate;
(3) Temperature shall be addressed to ensure no
impact on the receiving waterway;
(4) 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;
(5) A conceptual project design meeting shall be
held with the appropriate Department staff and Soil Conservation District staff
to identify necessary stabilization measures; and
(6) All encroachments proposed under this section
shall be subject to review and approval by the Department.
d. A stream corridor protection plan may be developed by a regional stormwater management planning committee as an element of a regional sto