The subdivision and/or site plan shall conform
to standards that will result in a well-planned community, protect
the health and safety of the residents and provide a desirable living
environment without unnecessarily adding to development costs. The
following improvements shall be required: off-street parking and loading,
signage, landscaping, common open space, lighting, streets and circulation,
water supply, sanitary sewers and stormwater management.
All streets shall be provided with manholes,
catch basins and pipes where the same may be necessary for proper
drainage. The requirements of this section shall not be satisfied
with the construction of dry wells.
A. General.
(1) The system shall be adequate to carry off the stormwater
and natural drainage water which originates within the drainage watershed(s).
The developer shall be responsible for demonstrating that his improvements
do not cause, increase or shift a drainage, flooding or erosion problem.
In general, an improvement will not be allowed to increase peak runoff
rates, and no stormwater runoff or natural drainage water shall be
so diverted as to overload existing drainage systems, to create flooding
or the need for additional drainage structures on other private properties
or public land without proper and approved provisions being made for
taking care of these conditions.
(2) Over-the-sidewalk, under-the-sidewalk and/or through-the-curb
drains for the purpose of disposing sump pump runoff is prohibited.
These facilities must outlet into an adequate watercourse or drainage
system.
(3) The developer shall be responsible for acquiring all
state and/or federal permits related to stream encroachment, wetland
or wetland buffers, etc., as may be necessary for the project and
for providing the appropriate municipal agency copies of the approvals
or permits.
B. Underdrains.
(1) Borings shall be taken by the applicant's engineer
at approximately four-hundred-foot intervals for all proposed streets.
If these borings indicate a seasonably high water table to be within
three feet of the proposed finished profile grade, a complete underdrainage
system shall be installed under the pavement. No underdrains in streets
shall be less than six inches in diameter. All underdrain pipes shall
be surrounded by a filter fabric and then a filter media of No. 57
coarse aggregate. The filter media shall extend from six inches below
the bottom of the underdrain pipe to the subgrade for a width of the
pipe diameter plus 12 inches. Filter fabric shall extend around the
entire perimeter of the filter media.
(2) Cleanouts shall be provided at all changes in line
or grade. However, the distance between cleanouts shall not exceed
400 feet. Cleanouts in roadways shall have separate twelve-inch-diameter
frame and cover designed to transfer traffic loads away from the riser.
In no case shall cleanouts be permitted in sanitary manholes. Underdrains
in the street shall be separated from the sanitary sewer by a horizontal
and vertical distance of at least one foot zero inches.
C. The rational method shall be used for pipeline and
inlet design. The system shall be designed to convey the runoff from
the twenty-five-year-return-frequency-storm event. Minor stream structures
(50 acres or less) should be designed for the fifty-year-storm event
and major stream structures at the one-hundred-year-storm event. The
SCS method as described in Technical Release No. 55 may be substituted
for drainage areas greater than five acres.
D. All major bridges and culverts shall be designed for
one-hundred-year-storm flow capacities.
E. All materials used in the construction of storm sewers,
bridges and other drainage structures shall be in accordance with
the Standard Specifications for Road and Bridge Construction of the
New Jersey Department of Transportation, current edition, and any
supplements, addenda and modifications thereto, unless otherwise specified
by the reviewing municipal agency. Modifications or changes of these
specifications may be requested by the applicant but may be implemented
only with the knowledge and written consent of the Township Engineer
after discussion with the reviewing municipal agency.
F. Pipe sizes shall in no instance be less than 18 inches
in diameter. Reinforced concrete pipe shall be used, except where
alternate materials are allowed by the Township Engineer in off-road
areas.
G. Drainage inlets shall be located at all intersections
to prevent surface runoff from crossing the intersection. Inlets shall
also be spaced along the sides of a street at intervals as required
to capture all gutter flow resulting from the design storm. Inlets
shall have a curb opening and bicycle-safe grates. Frames and grates
shall be Campbell Foundry Company Pattern No. 2618 or its equal. Access
manholes shall be placed at maximum five-hundred-foot intervals throughout
the system, at pipe junctions where there are no drainage inlets,
and wherever there is a change in direction or in grade. Manholes
may be brick, block or precast. The smaller opening in the cone section
of the manhole shall be 30 inches. The diameter of the cover shall
be 30 inches. All frames and covers are to be rated for heavy traffic
and shall be Campbell Foundry Company Pattern No. 1012A or its equivalent.
H. Development plans shall show both the plan and profile
for the drainage systems. The plan shall also show all other buried
utilities, and utility crossings shall be shown in the profile.
I. Storm drains shall normally be located between curblines.
Sufficient inlets and manholes shall be installed to minimize utility
crossings.
J. All discharges shall be analyzed for stability. Headwalls
or flared end sections shall be installed. Riprap apron calculations
are to be submitted. All aprons are to be installed on a flat grade.
Minimum recommended median stone diameter (d50) shall be six inches.
K. Lots shall be graded to secure proper drainage away
from the buildings. Additionally, drainage shall be provided in a
manner which will prevent the collection of stormwater in pools or
other unauthorized concentrations of flow, and to the greatest extent
possible, water shall not flow across adjacent property lines.
L. Stormwater management structures.
(1) Detention basins (or retention basins upon specific
approval by the Board) shall be required to hold stormwater runoff
such that discharge from the site will not exceed predevelopment rates.
A waiver of this provision may be granted only when the applicant
shows that it will not adversely affect downstream properties nor
increase flood dangers.
(2) Detention basins are to be the preferred alternate.
Retention basins may be allowed if the applicant can demonstrate that
there are no practical locations for full discharge from the basin.
Alternate means to attenuate or retain stormwater runoff will be considered
on a case-by-case basis.
(3) Basins are to be designed so that peak runoff from
the post-development twenty-five-year-return-frequency-storm event
does not exceed the predevelopment ten-year-return-frequency-storm
event.
(4) The applicant must demonstrate that there will be
no increase in the two-year- and one-hundred-year-storm-event runoff
between the pre- and post-development conditions.
(5) Basins may be designed using either the SCS method
as described in Technical Release No. 55 or by the modified rational
method. If the modified rational method is used, the trailing leg
of the inflow hydrograph shall have a time twice the computed time
of concentration.
(6) All basins shall include an emergency spillway designed
to pass the full one-hundred-year-storm-event inflow without causing
damage to downstream properties or erosion of the embankment or soils.
(7) The submitted drawings are to show all topographical
features and structures downstream of all basin discharges for a sufficient
distance to evaluate the impact of discharge.
(8) Outfall structures shall be designed for easy access
for maintenance. Trash racks designed to be cleaned by rakes from
any accessible location are to be used on openings less than 12 inches.
Velocities through trash racks shall be less than two feet per second.
(9) Computation of existing flow conditions shall assume
a "good" hydrologic condition. A "brush" cover type will be assumed
unless other types of cover can be documented.
(10)
Computations for proposed conditions shall not
use a woods or brush condition, unless portions of the property are
deed restricted to remain in a natural condition.
(11)
Computations are to be submitted to back up
runoff coefficients, time of concentration, spillway and outfall design
and runoff computations.
(12)
Two soil borings are to be taken within the
basin areas, drilled to at least three feet below the bottom elevation
of detention basins and five feet below the bottom of retention basins.
Soil strata and the seasonal high groundwater table shall be determined.
(13)
The bottom of detention basins shall generally
be two feet above the seasonal high groundwater table. Retention basins
shall generally have three feet of clearance. Lower basins may be
allowed with underdrains or special vegetative plantings under special
site conditions.
(14)
Two percolation or permeability tests are required
for each retention basin at the proposed bottom elevation. Calculations
should demonstrate that the full basin can discharge within 18 hours
after the storm event. Additional percolation tests will be required
for basins greater than 5,000 square feet in area.
(15)
All basins shall be designed with one foot of
freeboard above the one-hundred-year stormwater surface. All inlets
leading to the basin shall also be one foot or more above the surface
elevation.
(16)
Basin side slopes shall be 3:1 or less.
(17)
Basin berms with a vertical elevation of five
feet from the outside toe of the dike to the emergency spillway (or
in the absence of an emergency spillway, the top of the dike) are
classified as a dam by N.J.A.C. 7:20. Appropriate state reviews and
permits are required.
(18)
Detention basin bottoms shall have a two-percent
slope to the outfall. Those with flatter bottoms may be approved with
concrete low-flow channels.
(19)
Where part of the contributing piping system
intercepts groundwater, a concrete low-flow channel will be provided.
(20)
Hydrologic analysis of the basins shall include
the full drainageshed. Drainage area maps shall be included in the
stormwater management report.
(21)
Where water quality standards apply, special
consideration is to be given to vegetation and to maintenance.
(22)
Landscaping near basins should not include species
of trees with leaves large enough to clog the orifices. Retention
basin bottoms must be kept clean of leaves at all times.
(23)
Retention basins are not to be designed for
alternate uses.
(24)
Post-construction percolation or permeability
tests will be required at retention basins to verify that the design
percolation rates have been obtained.
(25)
All plans for basins shall address post-construction
restoration and maintenance. Maintenance shall include but not be
limited to an inspection schedule, desilting, mowing and debris removal.
(26)
Grass and leaves.
(a)
If a grassed basin, mowing should be performed
when grass is between four and six inches high. The grass should never
be allowed to exceed six inches in height. All clippings must be removed
from the basin immediately following mowing.
(b)
Removal of leaves from the basin during the
fall is also required.
(27)
For retention basins, the schedule should indicate
that every five years the basin bottom will be scarified to a depth
of four inches to remove sediments and silts. Then, four inches of
granular topsoil must be added and the surface reseeded as detailed
previously.
(28)
For wet basins, a procedure to control aquatic
growth must be included.
(29)
At no time after final basin grading and permanent
stabilization should any equipment be allowed to operate within retention
basins which could smear or compact the soils leading to a reduction
in the percolation rate. This includes mowing and the annual removal
of accumulated silt. This does not pertain to the reestablishment
of the basin bottom every five years.
(30)
A cash contribution by the developer will be
provided to establish a basin maintenance trust for the Township or
other responsible agency. A minimum contribution of $10,000 will be
required to be deposited into an interest-bearing reinvestment trust
established for the sole purpose of future basin maintenance and repair.
(31)
All basins, regardless of ownership, must have
a dedicated access from a public right-of-way. The access should include
a stabilized hard surface suitable for the passage of maintenance
and inspection equipment and vehicles.
M. Detention or retention basins utilized and maintained
by several property owners within a drainage basin are encouraged,
and the feasibility of such joint facilities must be examined by the
applicant and reported upon to the Township Engineer.
N. Approval of drainage structures shall be obtained
from the appropriate municipal, county, state and federal agencies
and offices. Final approval shall not be effective until letters of
approval from the proper government authorities shall be furnished
to the Secretary of the Planning Board or the Secretary of the Zoning
Board of Adjustment, as the case may be, with a copy of each letter
forwarded to the Township Engineer.
O. When required by the Township and as indicated on
an approved development plan, a drainage right-of-way easement shall
be provided to the Township where a tract or lot is traversed by a
watercourse, surface or underground drainageway or drainage system,
channel or stream. The drainage right-of-way easement shall conform
substantially to the lines of such watercourse and, in any event,
shall meet any minimum widths and locations as shown on any adopted
Official Map or Master Plan. Such easement shall be expressed on the
plat as follows: "Drainage easement granted for the purpose provided
and expressed in the Land Development Ordinance of Mantua Township."
P. All construction shall be in accordance with the construction
standards promulgated by the Township Engineer.
General design requirements for all nonresidential
districts are as follows:
A. No merchandise, products, waste equipment or similar
material or objects shall be displayed or stored outside.
B. All buildings shall be compatibly designed, whether
constructed all at one time or in stages over a period of time. All
building walls facing any street or residential district line shall
be suitably finished for aesthetic purposes.
C. All portions of the property not utilized by buildings
or paved surfaces shall be landscaped.
D. The established grades on the site shall be planned
for both aesthetic and drainage purposes. The grading plan, drainage
facilities and landscaping shall be coordinated to prevent erosion
and siltation as well as assuring that the capacity of any natural
or man-made drainage system is sufficient to handle the water generated
and anticipated both from the site and contributing upstream areas.
E. Trash enclosures must be enclosed behind an opaque
fence or wall at least five feet in height, with an opaque self-closing
gate. The exterior finish material of the trash enclosure and gate
must be compatible with that of the exterior of the principal structure.
F. No tract shall be permitted more than one point of
ingress and/or egress within 75 feet of another point of ingress and/or
egress serving the same tract, and in no case shall a development
have more than two such points of ingress and/or egress on any one
street frontage.
[Added 4-7-2014 by Ord. No. O-3-2014]
A. The scale of buildings shall be broken up both horizontally and vertically
with offsets to reinforce the human scale.
B. No commercial statements of the occupant's products or services shall
be allowed as part of the building facade or elevation.
C. Architectural designs shall be evaluated in terms of the sensitive
integration of form, textures, and colors with the particular landscape
and topographic characteristics of each individual site.
D. Groups of related buildings shall be designed to present a harmonious
appearance in terms of style and use of exterior materials, fenestration
and roof type.
E. Building exterior walls shall be articulated to reduce the scale
and the uniform appearance of buildings and to provide visual interest
that will be consistent with the community's identity, character and
scale. The intent is to encourage a more human scale that residents
and workers will be able to identify with their community. As such,
one or a combination of the following shall be utilized in a development:
(2)
Arcades, display windows and entry areas.
(3)
Grouping into smaller or multiple structures.
(4)
Mature landscaping and landform manipulation.
(5)
Wall texture placement and change.
(6)
Clustering small-scale elements such as planter walls around
the major form.
(7)
Creation of a horizontal and vertical shadow line.
(8)
Offsets and/or breaks in the building line.
F. Each building shall be sensitive to the immediate neighboring structure.
Opportunities to provide walkway systems to adjoining buildings, including
common plazas or courtyards, are encouraged.
G. All facades of a building which are visible from adjoining properties
and/or public streets should contribute to the pleasing scale features
of the building and encourage community integration by featuring characteristics
similar to the front facade.
H. The exterior walls of each building shall be constructed of durable
permanent architectural materials compatible with campus-like standards,
tastefully handled, i.e., carefully selected brick; stone with a weathered
face or polished, fluted, or broken-faced. Exterior building materials
may include smooth-faced concrete block, tilt-up concrete panels or
prefabricated steel panels as secondary accent materials only.
I. Pre-engineered metal buildings, industrial-type structures featuring predominantly painted exteriors, and corrugated metal-sided or clapboard aluminum-sided. Butler-type buildings shall not be permitted, except as indicated in Chapter
230, Section 46 (§
230-46).
[Amended 12-20-2021 by Ord. No. O-19-2021]
J. All facade materials must be low-maintenance. There shall be no exposed
common concrete block on the exterior of any building, and painted
concrete block shall not be permitted.
K. Window treatment shall be required along the front and sides of all
buildings. The use of multifloor glass curtain walls should be avoided.
L. Drainage pipes and roof leaders on building surfaces must be located
on the interior and not exposed.
M. Building roofs are to be uncluttered. Vertical roof projections such
as towers, vents, stacks or roof-mounted equipment shall be integrated
into the architecture. All penetrations through the roof (i.e., mechanical
equipment or skylights) must be organized in a manner that is integral
to the architectural form of the building or be completely screened
from view by parapet walls or approved enclosures. Screens shall be
attractive in appearance and reflect or complement the architecture
of the building to which they belong.
N. The design of canopies shall be in keeping with the design of the
building.