It is hereby found that uncontrolled stormwater
runoff and flooding endanger life and damage public and private property,
that this condition is aggravated by encroachments in the floodplain
which contribute to flooding conditions by decreasing flood storage
volumes, and that the most appropriate method of alleviating flooding
conditions is through the regulation of both stormwater management
and stream encroachments, and that such regulations are within the
exercise of the police power of the Township for the protection of
the persons and property of its inhabitants and for the preservation
of the health, safety and general welfare.
Any application for development in the Township
shall include sufficient information to carry out the intent and purpose
of this article, which shall be administered by the Township Engineer
in conjunction with approval by the Board. Special attention shall
be given to proper sites for stormwater detention and surface drainage
and groundwater recharge so that the surface water will not adversely
affect neighboring properties or the public storm drainage system.
In the preparation of a stormwater management
plan, the following general principals shall be adhered to:
A.
Stormwater management systems shall emphasize a natural,
as opposed to an engineered, drainage strategy. The extent of natural
approach depends on such factors as site storage capacity, open channel
hydraulic capacity, recharge capability and maintenance needs and
resources. The extent of the stormwater management design shall be
assessed through the use of the New Jersey Department of Environmental
Protection (NJDEP) "New Jersey Nonstructural Stormwater Management
Strategies Point System" (NSPS) or such other analysis technique suitable
to the municipal approving authority.
B.
Maximum use shall be made of presently existing stormwater
runoff control devices, mechanisms or areas, such as existing berms,
terraces, grass waterways, favorable hydrologic soils, swamps, swales,
watercourses, woodlands and floodplains, as well as any proposed management
structures.
C.
Whenever practicable, planned or cluster development
shall be employed and permitted if it will reduce the total area of
impervious surfaces and preserve open space and topographic features
critical to stormwater management.
D.
Evaluation shall be made of the nature of the subwatershed
of which the site is a part and of the receiving stream channel capacities.
E.
Stormwater runoff shall not be transferred from one
subwatershed to another.
F.
The plan should coordinate with the soil erosion sediment
control plan.
G.
To the greatest possible extent, the plan shall avoid
the concentration of flow and shall provide for dissipation of velocities
at all concentrated discharge points.
H.
Reestablishing vegetative cover shall be in accordance
with the Standards and Specifications for Soil Erosion and Sediment
Control in New Jersey, latest edition.
I.
Timing for the plan shall establish permanent stormwater
management measures prior to construction or other land disturbance,
to include seeding and establishing sod in grass waterways.
A.
For calculating runoff amounts and for design of controls,
the provisions of Subchapter 7, entitled "Stormwater Management of
the Residential Site Improvement Standards," N.J.A.C. 5:21-7.1 et
seq., shall be employed.
B.
All stormwater management techniques and devices shall
conform to the provisions of the NJDEP provisions for Stormwater Management
as set forth in N.J.A.C. 7:8. The following subchapters shall be specifically
included:
(1)
Definitions shall be as set forth in N.J.A.C. 7:8-1.2,
with the following additions or modifications, which shall be applicable
to this article only and as may be referred to in references to this
article:
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"County Review Agency" shall mean the "Warren
County Planning Board."
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"Municipality" shall mean the "Township of Mansfield,
Warren County, New Jersey."
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"N.J.A.C." means the "New Jersey Administrative
Code."
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"NJDEP" means the "New Jersey Department of
Environmental Protection."
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"NSPS" means the "Nonstructural Stormwater Management
Strategies Point System" as published by the NJDEP.
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(2)
Applicability shall be as set forth in N.J.A.C. 7:8-1.6(a)
and (b).
(3)
Design and performance standards shall be as set forth
in N.J.A.C. 7:8-5, except as follows:
(a)
Article 5.3(a) shall be supplemented as follows:
The applicant shall demonstrate through the use of the NSPS the degree
of conformance with these regulations.
(b)
Article 5.3(c), setting forth standards for
land incorporated into nonstructural stormwater management measures,
shall be changed to read as follows:
[1]
Any land area used as a nonstructural stormwater
management measure to meet the performance standards in N.J.A.C. 7:8-5.4
and 5.5 shall comply with at least one of the following:
[a]
Be dedicated to a government agency
(subject to the concurrence and approval of said agency);
[b]
Subjected to a conservation restriction
filed with the Warren County Clerk's office; or
[c]
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.
[2]
Any land subject to the provisions of Subsection
B(3)(b)[1][a], [b], or [c] above, except that land dedicated and accepted
by Mansfield Township shall also be subject to maintenance, inspection
and reporting provisions as required by N.J.A.C. 7.8-5.8, entitled
"Maintenance Requirements," and the requirements of the stormwater
NJPDES permit issued to Mansfield Township and N.J.A.C. 7:14A-25.7.
An agreement shall be drawn between the Township and the party designated
to provide maintenance and inspection services. In addition, a bond
in accordance with the provisions of N.J.A.C. 7:8-5.8(i).
[3]
Provisions shall be made to require that the
party providing maintenance and inspection shall on an annual basis
and at least two months prior to the required reporting date of the
Township (April 30 at the writing of this chapter, subject to change
by NJDEP) provide to the Township
a completed copy of the municipal annual reporting form (provided
by the Mansfield Township Stormwater Management Coordinator) for the
subject property including the required certifications. In addition,
the Township shall have the right to audit the information within
the report.
(c)
Safety standards shall be as set forth in N.J.A.C.
7:8-6.
(4)
Erosion control, groundwater recharge and runoff quantity
standards shall be as set forth in N.J.A.C. 7:8-5.4.
(5)
Stormwater runoff quality standards shall be as set
forth in N.J.A.C. 7:8-5.5.
(6)
Calculation of stormwater runoff and groundwater recharge
shall be as set forth in N.J.A.C. 7:8-5.6, provided that where the
standards in this section are in conflict with the standards in the
Residential Site Improvement Standards, then the standards herein
shall control.
(7)
Standards for structural stormwater management measures
shall be as set forth in N.J.A.C. 7:8-5.7 except as set forth as follows:
(a)
Article 7:8-5.7(a)1 shall be amended to require
that a plan indicating the location and method of determination of
each environmentally critical area shall be supplied.
(8)
Maintenance requirements shall be as set forth in
N.J.A.C. 7:8-5.8.
No structure shall be built on a lot, any side
of which fronts on a natural watercourse unless a permit or certificate
of exemption has been issued by the New Jersey Department of Environmental
Protection or as appropriate by the Township of Mansfield, as follows:
