It is hereby determined that the lakes and waterways
within the Borough of Wanaque are at times subjected to flooding,
that such flooding is a danger to the lives and property of the public;
that such flooding is a danger to the natural resources of the Borough
of Wanaque, county and state; that development tends to accentuate
such flooding by increasing stormwater runoff, due to alteration of
the hydrologic response of the watershed in changing from the undeveloped
to the developed condition; that such increased flooding produced
by the development of real property contributes increased quantities
of water-borne pollutants and tends to increase channel erosion; that
such increased flooding, increased erosion and increased pollution
constitutes deterioration of the water resources of the Borough of
Wanaque, in the county and the state; and that such increased flooding,
increased erosion and increased pollution can be controlled to some
extent by the regulation of stormwater runoff from such development.
It is therefore determined that it is in the public interest to regulate
the development of real property and to establish standards to regulate
the additional discharge of stormwater runoff from such developments
as provided in this article.
The provisions of this article shall be applicable
to each of the types of development named below.
A. All site plans and subdivision plans that will add one or more acres of impervious surface, except as provided in §
95-3 below.
B. Any construction of one or more of the following uses:
(1) Confined feeding and holding areas that provide for
more than 100 head of cattle, 15,000 head of poultry, 500 swine, 4,000
turkeys or 10,000 ducks; this section shall also apply to all other
equivalent numbers of animal units as determined by the Soil Conservation
Service procedure for measuring BOD-producing potential.
(2) Pipelines, storage or distribution systems for petroleum
products or chemicals.
(3) Storage, distribution or treatment facilities, excluding
on-site sewage disposal systems, for liquid waste.
(4) Solid waste storage, disposition, incineration or
landfill.
(5) Quarries, mines or borrow pits.
(6) Land application of sludge or effluents.
(7) Storage, distribution or treatment facilities for
radioactive wastes, except where permitted and subject to a New Jersey
Pollutant Discharge Elimination System (NJPDES) permit or an approved
DPCC Plan.
C. In the event that control of stormwater runoff is
mandated in certain areas for construction covering less than one
acre of ground, such lesser developments shall come under provisions
of this article.
D. In the case of projects for which county as well as
municipal approval of proposed drainage facilities is required, the
applicants shall be required to comply with all provisions of this
article. In such a case, the only provisions of the municipal ordinance
which shall govern are those requirements which are stricter than
those of the county.
Each proposed project not exempted from the
operation of this article shall meet the following storm drainage
standards:
A. General standards. The project plans submitted shall
demonstrate careful consideration of the general and specific concerns,
values and standards of the Municipal Master Plan and applicable county,
regional and state storm drainage control programs and any County
Mosquito Commission control standards and shall be based on environmentally
sound site planning, engineering and architectural techniques.
B. Alternatives to detention basins.
(1) It is not necessary that basic requirements be satisfied
by means of detention basins. Storage tanks, infiltration pits or
dry wells may be used for the purpose, with appropriate consideration
for length of life and feasibility of continued maintenance.
(2) Nonstructural management practices, such as cluster
land use development, open space acquisition, stream encroachment
and flood hazard controls should be coordinated with detention requirements.
Changes in land use can often reduce the scope and cost of detention
provisions required by means of appropriate changes in runoff coefficients.
C. Specific standards.
(1) Flood and erosion control. A detention facility must
accommodate site runoff generated for two-year, ten-year, twenty-five-year
and one-hundred-year twenty-four-hour storms considered individually
(in each case a Type III rainfall as defined in Soil Conservation
Service publications). Runoff greater than that occurring from the
one-hundred-year, twenty-four-hour storm will be passed over an emergency
spillway. Detention will be provided such that, after development
neither the peak rate of flow from the site, nor the total flow during
the hour of maximum releases will exceed the corresponding flows which
would have been created by similar storms prior to development. For
purposes of computing runoff, all lands in the site shall be assumed,
prior to development, to be in good condition, if the lands are pastures,
lawns or parks; with good cover, if the lands are woods; or with conservation
treatment if the land is cultivated, regardless of conditions existing
at the time of computation.
[Amended 11-9-1988 by Ord. No. 10-88-88]
(2) Water quality control. In order to enhance water quality
of stormwater runoff, all stormwater management plans must provide
for the control of a water quality design storm. The water quality
design storm shall be defined as the one-year-frequency Soil Conservation
Service Type III twenty-four-hour storm or a one-and-one-fourth inch,
two-hour rainfall. The water quality design storm shall be controlled
by one of the following practices.
(a)
In dry detention basins, provisions shall be
made to ensure that the runoff from the water quality design storm
is retained such that not more than 90% will be evacuated prior to
36 hours for all nonresidential projects or 18 hours for all residential
projects. The retention time shall be considered a brim-drawdown time
and, therefore, shall begin at the time of peak storage. The retention
time shall be reduced in any case which would require an outlet size
diameter of three inches or less. Therefore, three-inch-diameter,
orifices shall be the minimum allowed.
(b)
In permanent ponds or wet basins, the water
quality requirements of this article shall be satisfied where the
volume of permanent water is at least three times the volume of runoff
produced by the water quality design storm.
(c)
Infiltration practices such as dry wells, infiltration
basins, infiltration trenches, buffer strips, etc., may be used to
satisfy this requirement provided that they produce zero runoff from
the water quality design storm and allow for complete infiltration
within 72 hours.
(3) In all cases, multiple-level outlets or other fully
automatic outlets shall be designed so that discharge rates from the
development for the design storms will not be increased from what
would occur if the development were not constructed. Outlet waters
shall be discharged from the development at such locations and velocities
as not to, cause additional erosion or cause additional channels downstream
of the development.
(4) Where the project consist of two phases, phase (a),
new construction which requires provisions of storm drainage under
the terms of this article, and phase (b), repair or rehabilitation
of structures and surfaces which does not result in increasing the
extent of impervious areas or in rendering existing surfaces less
pervious, the detention requirements may be computed on the basis
of phase (a) exclusively.
(5) If detention basins or other detention facilities
are provided through which water passes at times other than following
rainfall, the Municipal Engineer should be consulted concerning design
criteria. It will be necessary for detention requirements to be met,
despite the necessity of passing certain low flows. This applies to
all on-stream or on-line detention basins.
(6) Outlets from detention facilities shall be designed
to function without manual, electric or mechanical controls.
(7) The retention of site runoff as required by this article
will result in the accumulation in the detention basin of sediment,
including particulate polluting substances, silt and debris. Provision
must be made for periodic removal of accumulated solid materials.
Computations for storage capacity shall include estimates for one
year's accumulation of solid materials.
(8) Dams. Any stormwater basin that impounds water through
the use of an artificial dike, levee or other barrier and raises the
water level five feet or more above the usual, mean low-water height
when measured from the downstream toe-of-dam to the emergency spillway
crest is classified as a dam and subject to N.J.A.C. 7:20, the New
Jersey Dam Safety Standards. All such dams must be designed, constructed,
operated and maintained in compliance with the rules of N.J.A.C. 7:20.
(9) In many instances, the provisions of separate detention
facilities for a number of single sites may be more expensive and
more difficult to maintain than provisions of joint facilities for
a number of sites. In such cases, the municipality will be willing
to consider provisions of joint detention facilities which will fulfill
the requirements of this regulation. In such cases, a properly planned
staged program of detention facilities may be approved by the municipality
in which compliance with some requirements may be postponed at early
stages while preliminary phases are being undertaken and construction
funds accumulated. The necessary planning to facilitate such arrangements
may be accomplished by Phase II planning under provisions of N.J.A.C.
7:8.
D. Detention facilities in flood hazard areas.
(1) Whenever practicable, developments and their stormwater
detention facilities should be beyond the extent of the flood hazard
area of a stream. When that is not possible and detention facilities
are proposed to be located partially or wholly within the flood hazard
area, as defined by the New Jersey Division of Water Resources, Bureau
of Floodplain Management, or other areas which are frequently flooded,
some storm conditions will make the facility ineffective at providing
retention of site runoff. This will happen if the stream is already
overflowing its banks and the detention basin, causing the basin to
be filled prior to the time it is needed. In such eases the standards
established in these regulations will be modified in order to give
only partial credit to detention capacities located within a flood
hazard area. The credit will vary in a ratio intended to reflect the
probability that storage in a detention basin will be available at
the time a storm occurs at the site.
(2) Detention storage provided below the elevation of
the edge of the one-hundred-year floodplain will be credited as effective
storage at a reduced proportion as indicated in the table below:
|
|
Size of Drainage Area*
|
---|
|
Elevation
|
Less than 5 Square Miles
|
5 to 100 Square Miles
|
Greater than 100 Square Miles
|
---|
|
Less than 2 feet below
|
40%
|
65%
|
90%
|
|
Between 2 feet and 4 feet below
|
25%
|
50%
|
75%
|
|
Over 4 feet below
|
10%
|
25%
|
50%
|
|
*NOTE: The area contributing floodwaters to
the flood hazard area at the site in question.
|
|
This effective detention storage will be required
to provide for drainage of the developed land in accordance with the
criteria already established in these regulations. However, the gross
storage considered for crediting will not exceed that which would
be filled by runoff of a one-hundred-year storm from the site.
|
(3) As an alternative to the approach stated in Subsection
D(2) above, if the developer can demonstrate that the detention provided would be effective, during runoff from the one-hundred-year twenty-four-hour Type II storm, peaking simultaneously at the site and on the flood hazard area, his plan will be accepted as complying with provisions of Subsection
D(2) above.
(4) In making computations under Subsection
D(2) or
(3) above, the volume of net fill added to the flood hazard area portion of the projects site will be subtracted from the capacity of effective detention storage provided. ("Net fill" is defined as the total amount of fill created incidental to the completion of the project less the amount of excavated material removed during the completion of the project, both measured below the elevation of the edge of the flood hazard area.)
(5) Where detention basins are proposed to be located in areas which are frequently flooded but have not been mapped as flood hazard areas, the provisions of either Subsection
D(2) or
(3) will be applied, utilizing the elevation of a computed one-hundred-year flood.
(6) Developers are also required to show compliance with
the flood hazard area regulations of the Department of Environmental
Protection.
E. Standards for stream corridor protection (recommended).
To the extent practicable and consistent with other site planning
criteria and with appropriate beneficial use of the site as a whole,
it is recommended that no alteration of the natural terrain should
occur and no impervious surfaces should be located within a stream
corridor. The corridor should include all floodplain areas, adjacent
slopes of 12% or greater, and contiguous areas where the depth of
the seasonal high-water table is one foot or less.
The following submissions shall be required
for each proposed project subject to review under this article. The
applicant is free to combine exhibits or otherwise consolidate the
required information, so long as all required information is clearly
presented.
A. Topographic base map. A topographic base map of the
site, and extending a minimum of 200 feet beyond the limits of the
proposed development, at a scale of one inch equals 20 feet, with
two-foot contour intervals. Scales of one inch equals 30 feet or one
inch equals 40 feet would be acceptable if the project area is very
large and the land slopes are less than 4%. The base map must be at
the same scale as the plans submitted for subdivision and/or site
plan review. The map shall indicate at least the following: existing
water surface drainage, marshlands, outlines of woodland cover, existing
man-made structures, road utilities, bearing and distances of property
lines and significant natural and man-made features not otherwise
shown.
[Amended 11-9-1988 by Ord. No. 10-88-88]
B. Vicinity map. Applicants must prepare a map at a scale
of one inch equals 400 feet or greater on a paper print of the latest
air photographs available, updated in the field to reflect current
conditions, showing the relationship of the proposed development to
significant features in the general surroundings. The map must indicate
at least the following: roads, pedestrianways, access to the site,
adjacent land uses, existing open space, public facilities, landmarks,
places of architectural and historic significance, utilities, drainage,
including, specifically, streams and other surface water shown on
United States Geological Survey and soils maps and other significant
features not otherwise shown.
C. Environmental site analysis. A written and graphic
description of the natural and man-made features of the site and its
environs. This description should include a discussion of soil conditions,
slopes, wetlands, vegetation and animal life on the site. Particular
attention should be given to unique, unusual or environmentally sensitive
features and to those that provide particular opportunities or constraints
for development.
D. Project description and site plan(s). A map or maps
at the scale of the topographical base map indicating the location
of proposed buildings, roads, parking areas, utilities, structural
facilities for detaining or recharging stormwater and sediment control
and other permanent structures. The map(s) shall also clearly show
areas where alterations in the natural terrain, cover and grade are
proposed and changes in natural cover, including lawns and other landscaping.
A written description of the site plan and justification of proposed
changes in natural conditions may also be provided.
E. Water detention facilities map. The following information,
illustrated on a map of the same scale as the topographic base map,
shall be included:
(1) Total area to be paved or built upon, estimated land
area to be occupied by water detention facilities and the type of
vegetation thereon and details of the proposed plan to control and
dispose of surface water.
(2) Details of all water detention plans, during and after
construction, including discharge provisions, discharge capacity for
each outlet at different levels of detention and emergency spillway
provisions with maximum discharge capacity of each spillway.
(3) Maximum discharge and total volume of runoff which
would occur from the project area before and after development for
the following storms:
(a)
One and one-fourth inches of rainfall occurring
within two hours or a one-year-frequency Type III twenty-four-hour
storm.
(b)
The specified design storms two-year, ten-year,
twenty-five-year and one-hundred-year twenty-four hour Soil Conservation
Survey Type III.
[Amended 11-9-1988 by Ord. No. 10-88-88]
F. The municipal official or board reviewing an application
under this article may, in consultation with the Municipal Engineer,
waive submission of any of the above requirements when the information
requested is impossible to obtain or when it would create a hardship
on the applicant to obtain and where its absence will not materially
affect the review process.
In addition to any fee due to the municipality
as a result of the applicants underlying application for a municipal
approval, there shall be due to the municipality at the time of submission
of materials in support of this application a fee as follows:
A. The application shall be submitted with a filing fee
of $250. In addition to the filing fee, the applicant will be requested
to post an escrow account to reimburse the borough for the actual
professional fee incurred, and if need be, during the course of the
procedure, the applicant will be required to make additional deposits
to cover professional fees rendered for the proper review of the application.
Any unused portion of the escrow is refundable to the applicant.
B. This fee is an approximation of the estimated cost
to the municipality to have its professional staff and consultants
review the proposed project.
Should any section or provision of this article
be declared invalid by a court of competent jurisdiction, such a declaration
shall not affect the remaining sections or provisions of this article
which are hereby declared to be severable.
this article shall take effect upon final passage
and approval by the County Planning Agency or Water Resources Association,
as appropriate, or 60 days after submission to said Agency if it fails
to act.