The subdivider shall observe the following requirements
and principles of land subdivision in the design of each subdivision
or portion thereof.
The subdivision plat shall conform to design
standards that will encourage good development patterns within the
borough. Where either or both an Official Map or Master Plan has or
have been adopted, the subdivision shall conform to the proposals
and conditions shown thereon. The streets, drainage, rights-of-way,
school sites, public parks and playgrounds shown on an officially
adopted Master Plan or Official Map shall be considered in approval
of subdivision plats. Where no Master Plan or Official Map exists,
streets and drainage rights-of-way shall be shown on the final plat
in accordance with Section 20 of Chapter 433 of the Laws of 1953[1] and shall be such as to lend themselves to the harmonious
development of the borough and enhance the public welfare in accordance
with the design standards in this section.
[1]
Editor's Note: See N.J.S.A. 40:55D-37 et seq.
A.
The arrangement of streets not shown on the Master
Plan or Official Map shall be such as to provide for the appropriate
extension of existing streets.
B.
Minor streets shall be so designated as to discourage
through traffic.
C.
Subdivisions abutting arterial streets shall provide
a marginal service road or reverse frontage with a buffer strip for
planting or some other means of separation of through and local traffic
as the Planning Board may determine appropriate.
E.
The right-of-way width for internal roads and alleys
in multifamily, commercial and industrial development shall be determined
on an individual basis and shall in all cases be of sufficient width
and design to safely accommodate the maximum traffic, parking and
loading needs and maximum access for fire-fighting equipment.
F.
No subdivision showing reserve strips controlling
access to streets shall be approved, except where the control and
disposal of land comprising such strips has been placed in the Borough
Council under conditions approved by the Planning Board.
G.
Subdivisions that adjoin or include existing streets
that do not conform to widths as shown on the Master Plan or Official
Map or the street width requirements of this chapter shall dedicate
additional width along either one or both sides of said road. If the
subdivision is along one side only, 1/2 of the required extra width
shall be dedicated.
H.
Street intersections shall be as nearly at right angles
as is possible and in no case shall be less than 60°. The block
corners at intersections shall be rounded at the curbline with a curve
having a radius of not less than 20 feet.
I.
Street jogs with center-line offsets of less than
125 feet shall be prohibited.
J.
A tangent at least 100 feet long shall be introduced
between reverse curves on arterial and collector streets.
K.
When connecting street lines deflect from each other
at any one point by more than 45° and not more than 45°, they
shall be connected by a curve with a radius of not less than 100 feet
for minor streets and 300 feet for arterial and collector streets.
L.
All changes in grade shall be connected by vertical
curves of sufficient radius to provide a smooth transition and proper
sight distance.
M.
Dead-end streets (culs-de-sac) shall not be longer
than 600 feet and shall provide a turnaround at the end with a radius
of not less than 60 feet and tangent whenever possible to the right
side of the street. If a dead-end street is of temporary nature and
the portion of the street to be immediately improved is more than
400 feet in length, a similar turnaround shall be provided and provisions
made for future extension of the street and reversion of the right-of-way
to the adjoining properties.
N.
No street shall have a name which will duplicate or
so nearly duplicate as to be confused with the names of existing streets.
The continuation of an existing street shall have the same name.
A.
Streets shall follow the natural contour of the land
wherever possible to avoid excessive land disturbance.
B.
Grades of major and minor collector streets shall
not exceed 8%. Grades on other streets shall not exceed 10%. No street
shall have a minimum grade of less than 1%.
C.
Intersections of any street with a major or minor
collector street shall have a maximum grade of 3% within 75 feet of
the street intersections.
D.
The street grade for local street intersections with
one another shall not exceed 4% within 50 feet of the street intersection.
E.
The grade on any cul-de-sac shall not exceed 8%.
F.
All changes in grade shall be connected by vertical
curves or sufficient radius to provide a smooth transition and proper
sight distance.
G.
Residential driveways intersecting streets shall not
exceed a grade of 12% and shall not exceed a grade of 6% within 30
feet of the street right-of-way in accordance with the AASHO Standards.
A.
Block length and width or acreage within bounding roads shall be such as to accommodate the size of lot required in the area by Chapter 233, Zoning, and provide for convenient access, circulation control and safety of street traffic.
B.
In blocks over 1,000 feet long, pedestrian crosswalks
may be required in locations deemed necessary by the Planning Board.
Such walkway shall be 10 feet wide and be straight from street to
street.
C.
For commercial group housing or industrial use, block
size shall be sufficient to meet all area and yard requirements for
such use.
C.
Each lot must front upon an approved street at least
50 feet in width, except lots radial to curved streets.
D.
Where extra width has been dedicated for widening
of existing streets, lots shall begin at such extra width line, and
all setbacks shall be measured from such line.
E.
Where there is a question as to the suitability of
a lot or lots for their intended use due to factors, such as rock
formations, flood conditions or similar circumstances, the Planning
Board may, after adequate investigation, note that such lots in their
present condition shall not be used for building purposes.
Except where otherwise indicated, the standards
set forth in this section shall be deemed mandatory.
A.
Utility easement. Easements along rear or side property
lines or elsewhere for utility installation may be required by the
approving authority if deemed necessary. Such easements, if required,
shall be at least 15 feet wide and located after a consultation with
public utility companies or agencies concerned.
B.
Preservation of natural features. Natural features,
such as trees, brooks, hilltops and views, shall be preserved wherever
possible in designating any subdivision containing such features.
No trees eight inches or larger in diameter shall be removed from
the subdivided plot unless the same shall interfere with the construction
of a building or buildings or utilities and unless approval for such
removal is received from the approving authority.
C.
Mandatory stormwater drainage standards. The drainage
systems shall be designed in conformance with accepted engineering
standards. A report on storm drainage calculations shall be prepared,
signed and sealed by a licensed professional engineer in the State
of New Jersey, in sufficient detail for a review of these calculations.
Included shall be maps, plats or other materials necessary to establish
areas tributary to the site as well as areas within the site tributary
to a specific watercourse of drainage structure, methodology for selection
of design variables and capacities of the proposed and existing systems.
D.
Design storms.
(1)
All stormwater drainage facilities shall be designed
in accordance with the following schedule of design storms:
|
Draninage Facilities
|
Return Frequency Storm
| |
|---|---|---|
|
Street inlets, catchbasins, connecting storm
drains
|
25 years
| |
|
Drainage channels, major culverts, piped watercourses,
detention/re- tention basins and associated piping
|
100 years
|
(3)
Hydraulic designs employing the Soil Conservation
Service method shall use the following twenty-four-hour precipitation
totals (Type II storm) for the indicated return frequency storm:
|
Ten-year: 5.1 inches.
| |
|
Twenty-five-year: 5.7 inches.
| |
|
One-hundred-year: 7.2 inches.
|
E.
Stormwater facilities. Stormwater facilities include
but are not limited to drywells, swales, basins, porous pavement watercourse
drainage pipes and structures or a combination of these or other methods.
F.
Maintain present runoff rate. All applications for subdivision and site plan approval shall be required to maintain the rate of stormwater runoff from the property to no more than the rate of runoff from the lands in its present state, both during and after construction, except as hereinafter provided under Article VIII, Design Standards, relating to detention areas.
G.
Methodology. Methodology for determining runoff shall
conform to one of the following:
(1)
Soil Conservation Service Runoff Equation, runoff
curve numbers and dimensionless unit hydrograph as described in National
Engineering Handbook - Section 4 - Hydrology, United States Department
of Agriculture, Soil Conservation 55 - Urban Hydrology for Small Watersheds,
United States Department of Agriculture, Soil Conservation Service,
Engineering Division, January 1975.
(2)
The Rational Formula and Runoff Coefficients, published
in the Handbook of Applied Hydrology, Ven Te Chow, Editor, McGraw-Hill,
1964.
H.
Storm drainage facilities. The following are mandatory
design standards for storm drainage facilities, where required:
(1)
Interceptor ditches. Interceptor ditches shall be
established above all cut and fill slopes where required by the Borough
Engineer to prevent erosion of the new slopes or excessive concentrations
of storm flows into preexisting developed areas. The intercepted water
shall be conveyed to a stable channel, watercourse or drainage structure
of adequate capacity.
(2)
Retention/detention basins. Stormwater retention/
detention basins may be depressions in parking areas, excavated basins,
basins created through use of curbs, stabilized earth berms or dikes,
rooftop storage or any other form of grading which serves to temporarily
impound stormwater. The following standards shall apply:
(a)
Where retention ponds are to be provided, dual
purpose controls for storing excess stormwater runoff and for setting
suspended matter in the stormwater shall be provided.
(b)
Where applicable, a routing study shall be provided
and shall conform to Technical Release 55 - Urban Hydrology for Small
Watersheds, United States Department of Agriculture, Soil Conservation
Service, Engineering Division, January 1975, or any other acceptable
method.
(c)
Peak discharge.
[1]
Detention areas shall be designed to contain stormwater discharges. Peak discharge from a one-hundred-year design storm after development shall be controlled to a rate of discharge equal to the peak discharge of a one-hundred-year design storm prior to development whenever the downstream drainage channels and structures are shown to be adequate for the preexisting storm flows. Whenever the downstream drainage channels are determined to be inadequate to safely carry the peak discharge from a one-hundred-year storm flow, the detention areas shall be designed to limit the stormwater discharge from the site to a rate equivalent to the peak discharge of a twenty-five-year design storm prior to development. Such provisions shall not constitute any waiver of the off-tract improvements provisions contained in Chapter 231, Site Plan Review, § 231-35.
[2]
Retention areas may be employed to reduce the
after development peak discharges to the limits described above. Retention
areas shall accept the excess surface waters from a one-hundred-year
design storm and absorb these waters within a seven-day period. One
percolation test and soil log is required for each 1/2 acre of surface
area of a proposed retention basin.
(d)
If earth berms or dikes are used to create the
impounding area, they shall be provided with an emergency spillway
or outlet structure to pass the one-hundred-year storm and shall be
adequately stabilized and the slopes protected with vegetative cover,
paving or riprap to protect against erosion, failure or breaching.
Spillways shall discharge into a suitable receiving structure or drainage
course.
(e)
Outlet structures shall be provided at detention
basins to regulate the outflow and shall also incorporate a spillway-type
overflow, capable of passing the design storm into the downstream
drainage facility. Downstream piping shall not be smaller than 15
inches diameter to facilitate cleaning. Trash racks, if required shall
be installed to prevent clogging of the outlet pipe. Maximum bar spacing
shall be six inches. Trash racks shall have area openings totaling
five times the open area of the outlet pipe.
(f)
Suitable linings of the embankment and channel
bed shall be placed upstream and downstream from principal inlets
or outlets to prevent scour and erosion.
(g)
Embankments shall have side slopes not steeper
than 1 to 2.
(h)
Safety berms shall be constructed when side
slopes steeper than have been specifically permitted by the Planning
Board (See Section 8C6) and where the basin is designed for a permanent
or residual pool of water. These berms shall be at least four feet
in width with one located one foot to 11/2 feet above and the other
located 21/2 to three feet below the permanent water surface.
(i)
Basins bottoms shall be designed to protect
against residual water ponding to prevent mosquito and insect infestation.
A low-flow channel shall be provided between inlet and outlet structures
and shall have a paved invert.
(j)
Fencing and/or vegetative screening may be required
around basins at the discretion of the Planning Board and to ensure
the safety of the public.
(k)
Basins shall be stabilized with suitable low
maintenance plant and natural materials consistent with the environment,
as approved by the Bergen County Soil Conservation Service and the
Borough Engineer.
(l)
The base of all retention and detention basins
shall be accessible to earthmoving equipment and vehicles for repair
and maintenance purposes. Loop or perimeter roads shall be constructed
around the basins as necessary to obtain access total outlet and inlet
structures.
(3)
Ground-absorption systems. Ground-absorption systems,
such as drywells, porous-piping systems or the like shall be used
only where the infiltration rate of the receiving soil is acceptable
as determined by percolation tests and soil logs, as required for
each absorption unit and in accordance with § 232-20H(b)[3].
(4)
Drainage channels.
(a)
Drainage channels shall be designed utilizing
the Manning Formula. One foot of freeboard above the design storm
flowline shall be provided. Channel lining shall be suitable for the
design velocity in accordance with Standards for Soil Erosion and
Sediment Control in New Jersey, adopted by the New Jersey State Soil
Conservation Committee as may be amended.
(b)
Where channel side slopes greater than 1 to
2 are permitted or where peak channel velocities under a ten-year
storm analysis are found to be in excess of the permissible channel
velocities as established in the aforementioned Soil Conservation
Service Standards, the channels shall be armored with riprap.
(5)
Pipe sizes.
(a)
The minimum pipe size shall be 15 inches and
pipes shall be of reinforced concrete. Pipe strength shall be adequate
to withstanding external loading but in no case shall it be less than
Class III strength.
(b)
Slopes shall be designed for all pipes so that
a minimum velocity of 21/2 feet per second shall be obtained when
the pipe is flowing 1/2 full.
(c)
Where pipe sizes are increased, the invert of
the larger pipe shall be dropped so that the crown of the pipes shall
be at the same elevation of the smaller pipe. All storm sewers shall
have a minimum cover of two feet.
(6)
Inlet.
(a)
Inlets or catchbasins shall be spaced so that
the run of water along any curbline does not exceed 300 feet, except
that the inlet spacing shall not be more than 250 feet on street grades
between 3% and 6% and not more than 200 feet apart on street grades
greater than 6% and not more than 200 feet apart on street grades
greater than 6% or less than 2%. Double basin inlets shall be provided
at the low point transition on all streets with grades 8% or greater.
Inlet spacing shall be reduced and additional basins installed as
necessary to ensure at least one eight-foot-wide lane remains open
in each direction during the twenty-five-year design storm.
(b)
Inlet grating shall be of the stream flow type
and gratings shall be sized to accept the entire contributory storm
flow under a maximum head of two inches and assuming a 30% clogging
factor for the gross area. Inlet gradings shall have a curb piece
and back plate unless otherwise approved. Bottom of inlets shall be
at the invert of the outlet piping.
(7)
Headwalls. Headwalls shall be provided at all drain-pipe
inlets and outlets. Side walls and training walls shall form an angle
of approximately 30° with the axis of flow. An apron shall be
provided extending a minimum of two pipe diameters beyond the end
of the discharge pipe. Aprons and walls shall be a minimum of 12 inches
thick and shall be constructed of 3,000 pounds per square inch air-entrained
concrete.
(8)
Drainageway.
(a)
Where a subdivision or site is traversed by
a natural stream, watercourse or drainageway, there shall be provided
a public drainageway conforming substantially with the lines of such
watercourses and such further width or construction, or both, as will
be adequate for the maintenance and clearing of the channel and banks.
(b)
The minimum drainageway width shall be 20 feet,
but shall provide at least a ten-foot width along the top of either
channel bank (wherever) for vehicular or equipment access (wherever
feasible) as required by the approving authority. The approving authority,
where it deems advisable, may require the conveyance of such drainageway
in fee simple to the borough.
(9)
Stream protection. All development applications shall
provide for the maintenance of the stream bed and its bank. Vegetation
and its subsurface root structure shall be protected. A stream buffer
of at least 20 feet measured from the top of the stream bank shall
be provided. Top of stream bank shall be considered as the flattened
area immediately bordering the stream course on which the water normally
flows.
