[Amended 8-25-97 by Ord. No. 97-25]
For residential development these standards are superseded by Residential Site Improvement Standards (N.J.A.C., Title 5, Chapter 21).
A. Required.
Sidewalks and curbs shall be constructed and installed on both sides of each street in accordance with specifications promulgated by the Department of Planning and Engineering.
B. Barrier Free Access.
At such points of intersection between sidewalks and streets as the Township Engineer shall decide, the sidewalk shall be constructed so as to slope gradually, to street level, at a gradient of not more than one (1) foot in twelve (12) feet, wherever possible, so as to provide ramp access for handicapped persons between the sidewalk and the street. The curb depression shall be a minimum width of three (3) feet. Construction shall be in accordance with standards prescribed by the New Jersey Department of Transportation.
C. Width.
Sidewalks shall be at least four (4) feet wide. When the Approving Authority determines that a sidewalk may be subject to unusually heavy pedestrian traffic or intended equally for bicycles it may require that its width be increased to either six (6) or eight (8) feet. In parking areas where sidewalks abut the curb and cars overhang the sidewalk area, the sidewalk shall be widened by two (2) feet.
D. Materials.
Sidewalks shall be constructed of concrete or brick material, as determined by the approving authority.
E. Concrete Specifications.
Materials shall conform to the N.J.D.O.T. Standard Specifications for Road and Bridge Construction in effect at the time of construction.
F. Other Materials.
Other material specifications shall be approved by the Township Engineer.
G. Subgrade.
The sidewalk subgrade shall be a six inch thick granular soil material approved by the Township Engineer and compacted prior to the placement of any sidewalk as directed by the Township Engineer.
H. Sidewalk Location.
In residential developments, sidewalks shall be placed in the right-of-way, parallel to the street, unless an exception has been permitted to preserve topographical or natural features, or to provide visual interest, or unless the applicant shows that an alternative pedestrian system provides safe and convenient circulation.
In planned developments and cluster developments, sidewalks may be located away from the road system to link dwelling units with other dwelling units, the street, and on-site activity centers such as parking areas and recreational areas. They may also be required parallel to the street for safety and other reasons.
I. Pedestrian Easements.
Pedestrian way easements ten (10) feet wide may be required by the Approving Authority through the center of blocks to provide circulation or access to schools, playgrounds, shopping, or other community facilities.
[Amended 8-25-97 by Ord. No. 97-25]
For residential development these standards are superseded by Residential Site Improvement Standards (N.J.A.C., Title 5, Chapter 21).
A. Required.
Sight easements shall be provided at each quadrant of an intersection of streets or streets and driveways and shall be shown on the plan. Any development requiring site plan or subdivision approval shall provide adequate sight easements at each driveway with the driveway classified as a local street for purposes of establishing distances.
B. Dedicated; easement.
The area within sight easement shall be kept as part of the lot and identified as a sight easement. The wording of the sight easement shall be subject to the review and approval of the Board Attorney.
C. Clearance.
No grading, planting or structure shall be erected or maintained higher than thirty (30) inches above the center-line grade of the intersecting street or driveway or lower than ten (10) feet above their center lines, excluding street name signs and official traffic regulation signs. Where any intersection involves earth banks or vegetation, including trees, the developer shall trim or selectively thin trees and grade to provide adequate sight distance. Within these sight easements, plantings should be restricted to low spreading varieties of plants and shrubs.
D. Area.
The sight easement is that area bounded by the intersecting street center lines and a straight line which connects sight points located on each of the two (2) intersecting street center lines. The sight easement distances shall be in accordance with A Policy on Geometric Design of Highways and Streets 1984 by American Association of State Highway and Transportation Officials.
E. Lot Area.
Portions of a lot set aside for the sight easement may be calculated in determining the lot area and may be included in establishing the minimum setbacks required by the zoning provisions.
All applications shall comply with the standards for Soil Erosion & Sediment Control in New Jersey by the New Jersey State Soil Conservation Committee. All plans shall incorporate soil erosion and sediment control programs phased according to the scheduled progress of the development, including anticipated starting and completion dates. The purpose Is to control soil erosion and sediment damages and related environmental damage by requiring adequate provisions for surface water retention and drainage and for the protection of exposed soil surfaces in order to promote the public health, safety, convenience and general welfare of the community. If no board approval or Freehold Soil Conservation Service approval is required the applicant shall submit a plan conforming to all aspects of this section.
A. General Design Principles.
1. Control measures shall apply to all aspects of the proposed land disturbances and shall be in operation during all stages of the disturbance activity. The following principles shall apply to the soil erosion and sediment control plan:
a. Stripping of vegetation , grading or other soil disturbance shall be done in a manner which will minimize soil erosion.
b. Whenever feasible, natural vegetation shall be retained and protected.
c. The extent of the disturbed area and the duration of its exposure shall be kept within practical limits.
d. Either temporary seeding, mulching or other suitable stabilization measures shall be used to protect exposed critical areas during construction or other land disturbances.
e. Drainage provisions shall accommodate increased runoff resulting from modified soil and surface conditions during and after development or land disturbance.
f. Water runoff shall be minimized and retained on site wherever possible to facilitate groundwater recharge.
h. Diversions, sediment basins and similar required structures shall be installed prior to any on-site grading or land disturbance.
2. All lots where fill material is deposited shall have clean fill and/or topsoil deposited which shall be graded to allow complete surface draining of the lot into local storm sewer systems or natural drainage courses. No regrading of a lot shall be permitted which would create or aggravate water stagnation or a drainage problem on site or on adjacent properties. Grading shall be limited to areas shown on an approved site plan or subdivision. Any topsoil disturbed during approved excavation and grading operations shall be redistributed throughout the site.
3. Excavation of soil other than as required for the construction of approved structures and supporting facilities, such as but not limited to streets, driveways and parking areas, shall be prohibited. Regrading of property so as to redistribute topsoil throughout the site from areas excavated shall be done to minimize or eliminate the erosion of soil.
B. Maintenance.
All erosion and sediment control measures installed shall be maintained for one (1) year after completion of the improvements or until such measures are permanently stabilized as determined by the Township Engineer, whichever is longer.
[Amended 12-13-93 by Ord. No. 93-74]
A. Required.
Solid wastes and recyclables, if stored outdoors, shall be placed in metal receptacles within a screened refuse area in accordance with the standard details on file in the Department of Planning and Engineering and subject to the following minimum standards:
1. The screened refuse area shall not be located within any front yard area.
2. The refuse storage area shall be surrounded on all sides. All commercial and industrial refuse storage area facilities shall be constructed of masonry material. All refuse storage areas shall contain swinging cedar gates and address the need for storage of recyclables. The height of the storage receptacle and stored refuse shall not exceed the height of the refuse storage area.
3. A five (5) foot minimum width landscaping area shall be provided along the fence or wall enclosing the refuse storage area. The landscaping to be provided shall be shown on the site plan submitted for approval. The planting shall be placed so at maturity the plants do not encroach upon the refuse container, nor result in an opening less than ten (1 0) feet for vehicle access.
4. The opening in the enclosed refuse area should be located to minimize the view of refuse from adjoining properties or public streets.
5. If located within or adjacent to a parking area or access drive, the enclosed refuse area shall be separated from such parking areas or access drive by curbing.
6. The enclosed refuse area shall not be located so as to interfere with traffic circulation or the parking of vehicles.
7. All refuse and recyclables shall be deposited in containers maintained within the refuse area. No containers shall be maintained anywhere on a site except in a refuse area meeting these requirements.
8. If outdoor storage of solid waste and recyclables is not proposed, the site plan submission shall detail the methods proposed for accommodating solid waste within the structure. The Approving Authority may require that a suitable area be set aside, but not improved, for a future solid waste storage area meeting these requirements even if indoor accommodations for solid waste are proposed.
B. Multifamily Housing Developments.
[Added 12-13-93 by Ord. No. 93-74]
1. In any new multifamily housing development an indoor or outdoor recycling area for the collection and storage of residentially-generated recyclable materials shall be provided. The dimensions of the recycling area shall be sufficient to accommodate recycling bins or containers which are of adequate size and number, and which are consistent with anticipated usage and with current methods of collection in the area in which the project is located. The dimensions of the recycling area and the bins or containers shall be determined in consultation with the municipal recycling coordinator, and shall be consistent with the district recycling plan adopted pursuant to section 3 of P.L. 1987, c. 102 (N.J.S.A. 13:1 E-99.13) and any applicable requirements of the municipal master plan, adopted pursuant to section 26 of P.L. 1987, c. 102.
2. The recycling area shall be conveniently located for the residential disposition of source separated recyclable materials, preferably near, but clearly separated from, a refuse dumpster.
3. The recycling area shall be well fit, and shall be safely and easily accessible by recycling personnel and vehicles. Collection vehicles shall be able to access the recycling area without interference from parked cars or other obstacles. Reasonable measures shall be taken to protect the recycling area, and the bins or containers placed therein, against theft of recyclable materials, bins or containers.
4. The recycling area or the bins or containers placed therein shall be designed so as to provide protection against adverse environmental conditions which might render the collected materials unmarketable. Any bins or containers which care used for the collection of recyclable paper or cardboard, and which are located in an outdoor recyclable area, shall be equipped with a lid, or otherwise covered, so as to keep the paper or cardboard dry.
5. Signs clearly identifying the recycling area and the materials accepted therein shall be posted adjacent to all points of access to the recycling area. Individual bins or containers shall be equipped with signs indicating the materials to be placed therein.
6. Screening shall be provided in accordance with 192-52A above around any outdoor recycling area.
[Amended 8-25-97 by Ord. No. 97-25; 227-06 by Ord. No. 06-05; 7-20-09 by Ord. No. 09-16]
For residential development these standards are superseded by Residential Site Improvement Standards (N.J.A.C., Title 5, Chapter 21).
A. Scope and Purpose
1. Policy Statement
Flood control, groundwater recharge, and pollutant reduction through nonstructural or low impact techniques shall be explored before relying on structural strategies. Structural strategies should 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 should be developed based upon physical site conditions and the origin, nature, and the anticipated quantity or amount of potential pollutants. Multiple stormwater management strategies may be necessary to achieve the established performance standards for water quality, quantity, and groundwater recharge.
2. Purpose
The purpose of this ordinance is to establish minimum stormwater management requirements and controls for "major development," which is defined in Chapter 132-3 as "Any development or redevelopment that provides for disturbance of one quarter (1/4) acre 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".
3. Applicability
a. 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:
(1) Non-residential major developments; and
(2) Aspects of residential major developments that are not pre-empted by the Residential Site Improvement Standards at N.J.A.C. 5:21.
(3) All major developments undertaken by East Brunswick Township
4. 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.
B. General Standards
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 herein. 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.
3. Stormwater management measures shall avoid adverse impacts of concentrated flow on habitat for threatened and endangered species as documented in the New Jersey Department of Environmental Protections's (NJDEP) 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).
4. The following linear development projects are exempt from the Groundwater Recharge, Stormwater Runoff Quantity, and Stormwater Runoff Quality requirements of this Section:
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.
5. The applicant may be required by the approving authority to carry away by pipe or open ditch any spring or surface water that may exist either previously to, or as a result of the application. Such drainage facilities shall be located in the road right-of-way where feasible, or in perpetual unobstructed easements of appropriate width, and shall be constructed in accordance with the Township construction standards and specifications.
6. All storm drainage shall be piped underground, except that where it is not feasible to pipe, open ditches may be constructed.
a. Where storm drainage is piped, an easement of not less than twenty-five (25) feet shall be shown on the approved plan and conveyed to the township.
b. Where the storm drainage flows in an open ditch, an easement of not less than fifty (50) feet shall be shown on the approved plan and shall be conveyed to the township.
The ditch shall be constructed so as to prevent erosion, be easily maintainable and shall be provided with safety features as it may deem necessary to protect and safeguard the public.
7. The applicant's Engineer shall also determine and identify to the Approving Authority the effect of each application on existing downstream drainage facilities outside the area of the application. Studies may be required of the applicant and, as shall be appropriate, shall serve as a guide to needed improvements.
8. Where in the opinion of the Township Engineer, underdrainage is required, the subdivider shall install subbase underdrains or Type F underdrains in accordance with the New Jersey State Highway Specifications of 1989 as amended and supplemented; and shall be of the size specified by the Township Engineer.
If in the opinion of the Township Engineer, and existing conditions exist, the applicant may be required to construct a (supac or equivalent filter fabric) lined ditch backfilled with 3/8" washed stone, with a minimum slope of 2% and concrete porous wall pipe set in the stone and connected to a downgrade inlet. Construction of such underdrains shall be in accordance with the standard details on file in the Department of Planning and Engineering.
All underdrain systems constructed within a site or subdivision shall be provided with a clean-out in accordance with the standards details on file in the Department of Planning and Engineering.
9. Subbase outlet drains when necessary, shall consist of stone pockets and/or trenches lined with filter fabric and filled with 3/8" broken stone, washed gravel or blast furnace slag, and discharge into an inlet or other appropriate facility or area. Subbase outlet drains shall be 6" c.m. pipe fully coated with half of pipe and end cap perforated or extra strength porous wall pipe with appropriate cap.
Subbase outlet drains will be required at low points in roadways and at other locations where necessary.
10. A waiver from strict compliance from the groundwater recharge, stormwater runoff quantity, and stormwater runoff quality requirements of this Section 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 each of 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;
b. 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 this Chapter's Erosion Control, Groundwater Recharge, Stormwater Runoff Quantity and Quality Design and Performance Standards (hereafter "the Design and Performance Standards") to the maximum extent practicable;
c. The applicant demonstrates that, in order to meet the requirements of the Design and Performance Standards, existing structures currently in use, such as homes and buildings, would need to be condemned; and
d. The applicant demonstrates that it does not own or have other rights to areas, including the potential to obtain through condemnation lands which do not include existing structures currently in use, such as homes and buildings within the upstream drainage area of the receiving stream, that would provide additional opportunities to mitigate the requirements of the Design and Performance Standards.
11. A waiver from strict compliance with the Township stormwater management design and performance standards may be obtained conditioned upon the positive recommendation of the Township Engineer and the applicant paying their fair share towards the implementation of the mitigation project(s) described in the Municipal Stormwater Management Plan adopted March 9, 2005. The mitigation project(s) to be funded shall be selected by the Township Engineer and shall be implemented in the same HUC 14 drainage area as the proposed development. The exact amount of the contribution shall be calculated by the Township Engineer and shall be based on the cost to comply with the particular standard for which the waiver or waivers are requested in proportion to the area/extent of site development proposed.
C. Nonstructural Stormwater Management Measures
1. To the maximum extent practicable, the Design and Performance Standards shall be met by incorporating nonstructural stormwater management strategies set forth in this Section 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 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;
(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 comply with this Section's standards to control passage of solid and floatable materials through storm drain inlets ;
(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.
(j) Swales may be constructed in which there need be no outlet facilities and which will impound water drainage only from other landscaped areas. The water impounded in these areas will be left to evaporate and percolate and the swales shall otherwise be seeded and maintained in lawn area. Minimum slope if grass or rip rap shall be two (2) percent. Minimum slope if concrete shall be .75 percent.
(k.) Any land area used as a nonstructural stormwater management measure to meet the Design and Performance Standards shall be subject to a conservation restriction filed with the Middlesex 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.
D. Calculation of Stormwater Runoff and Groundwater Recharge
1. Stormwater runoff shall be calculated in accordance with the following:
a. The design engineer shall calculate runoff using one of the following runoff coefficient calculation methods:
(1) The USDA Natural Resources Conservation Service (NRCS) methodology, including the NRCS Runoff Equation and Dimensionless Unit Hydrograph, as described in the NRCS National Engineering Handbook Section 4 Hydrology and Technical Release 55 Urban Hydrology for Small Watersheds; or
(2) The Rational Method for peak flow and the Modified Rational Method for hydrograph computations.
b. For the purpose of calculating runoff coefficients and groundwater recharge, there is a presumption that the pre-construction condition of a site or portion thereof is a wooded land use with good hydrologic condition. A runoff coefficient or a groundwater recharge land cover for an existing condition may be used on all or a portion of the site if the design engineer verifies that the hydrologic condition has existed on the site or portion of the site for at least five years without interruption prior to the time of application. If more than one land cover has existed on the site during the five years immediately prior to the time of application, the land cover with the lowest runoff potential shall be used for the computations. In addition, there is the presumption that the site is in good hydrologic condition (if the land use type is pasture, lawn, or park) with good cover (if the land use type is woods) or with good hydrologic condition and conservation treatment (if the land use type is cultivation).
c. In computing pre-construction 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 pre-construction stormwater runoff rates and volumes.
d. 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.
e. 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.
2. Groundwater recharge may be calculated in accordance with 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 http://www.state.nj.us/dep/njgs/; or at New Jersey Geological Survey, 29 Arctic Parkway, P.O. Box 427 Trenton, New Jersey 08625-0427; (609) 984-6587.
E. Standards for Structural Stormwater Management Measures
1. Standards for structural stormwater management measures are as follows:
a. Structural stormwater management measures shall be designed to take into account the existing site conditions, including, for example, 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).
b. Structural stormwater management m easures shall be designed to minimize maintenance, facilitate maintenance and repairs, and ensure proper functioning.
c. Structural stormwater management measures shall be designed, constructed, and installed to be structurally sound, 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.
d. At the intake to the outlet from the stormwater m anagement basin, the orifice size shall be a minimum of two and one-half inches in diameter.
e. Stormwater management basins shall be designed to meet the minimum safety standards for stormwater management basins detailed herein.
f. The pipe size shall be determined by acceptable drainage design procedures. In no case shall the pipe size in a surface water drainage system be less than fifteen (15) inches in diameter.
g. All pipe terminations shall be provided with poured concrete headwalls or precast concrete end sections in accordance with the approved preliminary plat or plan. Poured concrete headwalls shall be wing-type headwalls with aprons and cut-off walls in accordance with the construction details contained herein. Flared end sections shall be provided with cut off walls.
h. Storm drain pipes running longitudinally along streets shall not be located under curbing. They shall be reinforced concrete pipe conforming to ASTM Designation C76, reinforced arch culvert conforming to ASTM Designation C-506 or reinforced concrete elliptical pipe conforming to ASTM Designation C-507. Joints shall be made with O-ring rubber gaskets.
i. No concrete pipe shall be laid on grades exceeding ten (10%) percent. Elliptical concrete storm drain pipes will be jointed using a preformed bituminous mastic pressure-type joint sealer.
j. All storm drains shall be laid in a straight line between inlets, manholes or other structures, except that the use of the fittings or factory curved or mitered pipe may be allowed by the Township Engineer when necessary to accommodate existing geometry or utilities.
k. Site design features that help 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 paragraph, "solid and floatable materials" means sediment, debris, trash, and other floating, suspended, or settleable solids.
(1) 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:
(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 (April 1996); or
(b) A different grate, if each individual clear space in that grate has an area o f no m ore 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 (noncurb-opening portion) of combination inlets, grates on stormsewer 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.
l. Whenever design engineers use a curb-opening inlet, a NJDOT Type "NEcoCurb Piece" with "Dump No Waste, Drains To Waterway" nameplate shall be utilized.
m. These standards which control passage of solid and floatable materials through storm drain inlets do not apply in the following instances:
(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 this Chapter's Stormwater Runoff Quality Standards are conveyed through any device (e.g., end of pipe netting facility, manufactured treatment device, or a catch basin hood) that is designed, a t 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
(c) Where flows a re 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 this Chapter's Stormwater Runoff Quality Standards; or
(d) Where the NJDEP, 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 o r destroy the New Jersey Register listed historic property.
2. Stormwater management guidelines are available in the New Jersey Stormwater Best M anagement P ractices M anual. O ther stormwater management measures may be utilized provided the design engineer demonstrates that the proposed measure and its design will accomplish the required water quantity, groundwater recharge and water quality design and performance standards established by this ordinance.
3. Manufactured treatment devices may be used to meet the Stormwater Quality requirements of this ordinance, provided the pollutant removal rates are verified by the New Jersey Corporation for Advanced Technology and certified by the Department.
F. Erosion Control, Groundwater Recharge and Runoff Quantity Design and Performance 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 design engineer shall, using the assumptions and factors for Stormwater Runoff and Groundwater Recharge calculations within this Chapter, either:
(1) 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
(2) 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. This groundwater recharge requirement does not apply to projects within an "urban redevelopment area".
c. The following types of stormwater shall not be recharged:
(1) Stormwater from areas of high pollutant loading.; 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."
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.
2. In order to control stormwater runoff quantity impacts, the design engineer shall, using the assumptions and factors for Stormwater Runoff calculations within this Chapter, 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, 10, and 100-year storm events do not exceed, at any point in time, the pre-construction runoff hydrographs for the same storm events;
b. 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;
c. 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 preconstruction peak runoff rates. The percentages apply only to the postconstruction 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 (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.
G. Calculations for Stormwater Runoff Quality
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 nonstructural and structural stormwater management measures.
