A.
Sanitary sewers.
(1)
Minimum requirements shall be as established by the
New York State Department of Environmental Conservation, pursuant
to Environmental Conservation Law § 17-0301, as amended
or changed, and Title 8 of said law (Environmental Conservation Law
§ 17-0801 et seq., as amended or changed).
(2)
Sewer mains shall be a minimum of eight inches in
diameter, except in those areas where the route within the development
is part of the Master Sewer Plan. In these areas, the sewer shall
be of the diameter called for in the Master Sewer Plan.
(3)
Manhole spacing shall be a maximum of 300 linear feet
(4)
The depth of the sewer shall provide for basement
drainage (or slab construction) of all homes within the development.
Where, because of topographic conditions, this provision cannot be
met, the Plan shall incorporate a note specifying those lots which
cannot be served in compliance with this requirement.
(5)
Elevations. Where storm drains are parallel the sanitary
sewer system, a minimum of two feet of vertical clearance between
the two systems shall be provided to permit the satisfactory installation
of laterals.
B.
Sewage lift stations.
(1)
Specific geographic and/or topographic areas may require
the use of sewage lift stations to transmit contributory flows to
the trunk sewer system. Lift stations shall incorporate the following
design requirements:
Storm drainage systems shall be generally designed
and provided to adequately convey anticipated runoffs occurring from
storms which occur with a frequency of once in 10 years, as indicated
in nomographs prepared by the Monroe County Planning Council.
A.
Removal of spring and surface water. The applicant
shall be required by the Planning Board to provide adequate drainage
systems to carry any spring or surface water that may exist either
previous to or as a result of the subdivision. Such drainage facilities
shall be located in the street right-of-way where feasible or in perpetual
unobstructed easements of such widths as designated in this chapter.
B.
Drainage structure to accommodate potential development
upstream. A culvert or other drainage facility shall, in each case,
be large enough to accommodate potential runoff from its entire upstream
drainage area, whether inside or outside the subdivision. The Town
Engineer shall approve the design and size of the facility based on
anticipated runoff under ultimate development bases on accepted engineering
criteria and parameters.
C.
Responsibility for drainage downstream. The applicant's
engineer shall also study the effect of each subdivision on the existing
downstream drainage facilities outside the area of the subdivision;
this study shall be reviewed by the Town Engineer. Where it is anticipated
that the additional runoff incident to the development of the subdivision
will overload an existing downstream drainage facility, the Planning
Board shall notify the Town Board of such potential condition. In
such case the Planning Board shall not approve the subdivision until
provision has been made for the improvement of said condition.
D.
Land subject to flooding. Land subject to flooding
or land deemed by the Planning Board to be uninhabitable shall not
be platted for residential occupancy, nor for such other uses as may
increase danger to health, life or property or aggravate the flood
hazard, but such land within the plat shall be set aside for such
uses as shall not be endangered by periodic or occasional inundation
or improved in a manner satisfactory to the Planning Board to remedy
said hazardous conditions.
E.
Flood hazard prevention. The applicant shall be required
to control soil erosion of land surface and drainage channels and
the prevention of inundation and excessive groundwater seepage by
comprehensive site grading and the establishment of adequate elevations
of buildings, building openings and roadways above the observed, anticipated
or computed water levels of storm sewers, streams, channels, floodplains,
retention basins and swales.
F.
Runoff computations.
(1)
Runoff shall be established from the rational formula
as follows:
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Q = AcI
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Where:
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Q = Runoff (cfs)
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A = Acreage of the drainage basin involved
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c = Coefficient of runoff (minimum for subdivision
development 0.40)
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I = Intensity of rainfall in inches per hour
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(2)
Minimum times of concentration can be assumed at 15
minutes.
(3)
Nomographs to determine factors for the computation
of the runoff shall be those as developed by the Monroe County Planning
Council.
(4)
The applicant's engineer shall submit the following
information regarding the design of storm drainage facilities with
the final map (scale of 1:24,000).
(a)
A USGS section map (scale of 1:24,000) with
the outline of the development and the drainage basin.
(b)
A tabular form (see Appendix B for typical format[1]) showing computed runoffs and design capacities of the
drainage system.
[1]
Editor's Note: Appendix B is included at the end of this chapter.
(5)
Points of discharge. Storm drainage shall be discharged
to recognized USGS drainage courses. This may require applicants to
obtain downstream easements from adjoining property owners to permit
this drainage across their properties. The applicant shall be required
to construct and maintain temporary silt settling basins at the point
of discharge into the stream. The basin shall be operable until the
completion of the subdivision.
G.
Storm drains. Storm drains shall conform to the following
specifications:
(1)
Minimum pipe sizes shall be 12 inches in diameter.
(2)
Minimum velocity when flowing full shall be three
feet per second.
(3)
Maximum manhole and catch basin spacing shall be 300
linear feet.
(4)
Builders (where necessary) shall provide backwater
valves on all laterals where the storm drain is at such an elevation
to permit gravity drainage from the basements adjacent to the system.
(5)
All outfall pipes must be reviewed by the Town Engineer
and Commissioner of Public Works.
H.
Storm laterals. Storm laterals, if required, shall
be six inches in diameter. Sump pumps and roof runoff shall not be
permitted to tie into the storm laterals directly unless requested
by the Commissioner of Public Works. Splash pads shall be required
for storm outlets.
I.
Catch basins. Catch basins shall be placed at all
low points and intersections with maximum spacing of 300 feet. Catch
basin leads shall only be connected to the storm drains at manholes
except in those areas where the storm drain is 24 inches in diameter
or greater.
J.
Storm manholes.
K.
Drainage easements. The minimum width for drainage
easements shall be 20 feet.[2]
(1)
Enclosed conduits and appurtenances. An easement not
less than 20 feet in width, sufficient to contain the enclosed conduit
and appurtenances thereof and to provide working space for personnel
and equipment for the service thereof, shall be indicated on the map
of the development and designated as follows: "Drainage Easement to
Town of Irondequoit." Drainage easements, insofar as possible, shall
be placed along or adjacent to lot boundary lines in a parallel or
straight alignment.
(2)
Easements for natural watercourses.
(a)
Natural primary watercourses which traverse a development shall be preserved by an easement of sufficient width, including overbanks, which will adequately pass the projected design flow. The gross allowable depth of flow shall not create a flood hazard to existing or proposed development and improvements. The channel and overbank widths, together with a minimum twenty-foot continuous maintenanceway on each side, shall constitute the floodway encroachment limits, as further defined under the EPOD District regulations of Chapter 235, Zoning.
(b)
In natural tertiary and secondary watercourses
which contain insufficient waterway area to convey the flow from the
ultimate development, but which may prove deficient only at infrequent
intervals and location, and where minor improvements could provide
an adequate channel and still preserve, in the main, the natural channel
beauty or fish and wildlife values, the applicant shall make such
minor channel improvements as are required to provide a channel which
would otherwise meet the conditions of this chapter. Additional widths
of scenic areas and areas of natural wetlands which, for economic
reasons or limited suitability, would not warrant improving for urban
development, may be dedicated by the applicant in addition to those
above. Areas offered for dedication to the town as drainage easements,
if considered of special interest to the town by the Planning Board,
may be considered by the Planning Board as dedication for the municipal
purposes of § 278 of the Town Law, as amended or changed,
and its authority thereunder.
(c)
Easements for constructed channels and appurtenances.
Earth channels constructed within the development shall have sufficient
easements dedicated to contain the top width of the channel, plus
a minimum twenty-foot wide continuous maintenanceway, one side for
channels less than 20 feet in width at water surface. A twenty-foot
wide continuous maintenanceway shall be provided on both sides of
a channel with a water surface width greater than 20 feet. The easements
for constructed channels shall be indicated on the map of the development
and designated as follows: "Drainage Easement to Town of Irondequoit."
Water mains shall conform to the specifications
of the Monroe County Water Authority or the Sea Breeze and Vicinity
Water District and local fire districts.
A.
The Planning Board shall, wherever possible, establish
the preservation of all natural features which add value to residential
developments and to the community, such as large trees or groves,
watercourses and falls, beaches, historic spots, vistas and similar
irreplaceable assets. No tree with a diameter of eight inches or more
as measured three feet above the base of the trunk shall be removed,
unless such tree is within the right-of-way of a street as shown on
the final plat or where impractical to retain. Removal of additional
trees shall be subject to the approval of the Planning Board.
A.
Pavement widths. Standard pavement widths shall comply
with the typical cross sections shown in the Appendix D.[1] Additional widths may be required by the Planning Board
upon findings that the same are required for public safety and convenience,
parking in commercial or public use areas, old roads which do not
provide the proper widths and where, as a consequence, additional
dedication is necessary.
[1]
Editor's Note: Appendix D is included at the end of this chapter.
B.
Horizontal alignment.
(1)
Except for local residential streets and rural streets
and roads, there shall be a tangent of at least 100 feet measured
at the center line between reverse curves.
(2)
Proper sight distances shall be provided with respect
to both horizontal and vertical alignment. Measured along the center
line, the sight distance shall be 400 feet for primary roads or major
thoroughfares; 200 feet for collector streets or roads and 100 feet
for local residential streets and rural streets and roads.
(3)
Proper sight lines shall be maintained at all intersections
of streets measured along the center line; there shall be a clear
sight triangle of 75 feet from points of intersection. Visibility
for purposes of traffic safety shall be provided within the triangular
area formed by intersecting street lines and the diagonal connecting
the end points of these lines. The distance as measured along the
intersecting street lines shall be a minimum of 75 feet from the point
of intersection for arterial and collector streets and 50 feet for
minor streets. No visual obstructions shall be permitted in this area,
including, but not limited to:
(4)
Right-angle intersections shall be used wherever practicable,
especially where local residential streets and rural streets and roads
empty into major or collector thoroughfares, and there shall be no
intersection angle measured at the center line of less than 75º.
(5)
Street curb intersections shall be rounded by a tangential
arc with a minimum radius of 30 feet for local residential streets
and rural streets and roads and 45 feet for intersections, including
collector streets or roads and primary roads or major thoroughfares.
(6)
Culs-de-sac shall not exceed 500 feet in length and
must be designed with a turnaround having an outside roadway diameter
of at least 100 feet and a street property line diameter of at least
120 feet.
(7)
Intersecting minor and secondary streets leading from
the same subdivision shall not empty into the same side of a major
thoroughfare at intervals less than 800 feet.
(8)
The minimum radius at the center line for curves on
primary roads or major thoroughfares shall be 500 feet; for collector
streets or roads, 300 feet; and for local residential streets and
rural streets and roads, 150 feet.
C.
Road grades. Road grades shall conform to the following
specifications:
D.
Concrete gutters or curbs. Concrete gutters or curbs
shall be provided along the edges of all roads to be dedicated to
the town.
E.
Sidewalks. Sidewalks shall conform to the specifications
and details herein included.
Where land areas are reserved for future connections
to adjacent parcels, all improvements, i.e., sanitary, storm, water,
roads, etc., shall be constructed to the common property line. This
requirement may be waived by the Planning Board.
The materials included herein are intended to
establish the necessary degree of excellence required for installation
within the town. Where other materials may be proposed in substitution
for those herein called for, the applicant or his or her agent shall
submit a written request to the Town Engineer for approval. When new
materials may be made available, their use may be permitted in limited
test sections with the restriction that, should these materials prove
unsatisfactory through the test period, as established by the Town
Engineer, they shall be removed and replaced with those herein called
for at no expense to the town.
A.
Main sewer.
(1)
Polyvinyl chloride (PVC) main sewer. Polyvinyl chloride
(PVC) sewer pipe for use as nonpressure lines in conveying sewage
wastes shall be supplied in accordance with ASTM D-3034 and/or the
latest revisions thereto. Eight-inch and twelve-inch pipe shall be
supplied in lengths of 13 feet. All tests required by the above specifications
shall be conducted in the continental United States, and the town's
authorized representative shall have access to witness these tests
at the purchaser's expense. Minimum strength classification shall
be SDR 35.
(2)
Ductile iron pipe (DIP) main sewer. Ductile iron pipe
(DIP) sewer pipe for use as nonpressure lines in conveying sewage
waste shall be supplied in accordance with AWWA C-151/ANSI A21.51,
thickness Class 50, with ANSI A21.4 cement mortar lining and seal
coating inside, bituminous coating outside and ANSI 21.11 push-on
joints.
B.
Sewer lateral pipe. For polyvinyl chloride (PVC) sewer
pipe for use in conveying domestic sewage from the property line to
the sewer main, strengths shall be ASTM D-3034/SDR 35 and ASTM D-2241/SDR
21.
C.
Polyvinyl chloride (PVC) force main. Polyvinyl chloride
(PVC) sewer pipe for use in conveying domestic sewage under pressure,
shall be supplied in accordance with ASTM D-2241/SDR 21, pressure-rated
pipe, 200 psi pressure rating, with elastometric gasket bell ends
and PVC fittings and adapters.
D.
Manholes.
(1)
All manholes shall be of precast reinforced concrete
sections manufactured in accordance with ASTM Specification C-478.
Riser sections shall have super O-joints and gaskets conforming to
ASTM C-443, except the taper of the joints shall be 2º with a
tolerance of 1/32 inch. Manhole bases may be preformed or poured in
the field. The roof slabs shall be precast of structural concrete,
reinforced to withstand a concentrated wheel load of eight tons, plus
one-hundred-percent impact. Either tapered, conical or slab tops will
be permitted for the top section.
(2)
Interior and exterior surfaces of all sanitary manholes
shall be sealed with heavy-duty coal tar coating which complies to
ASTM D-450, Type B, as approved by the Town Engineer.
A.
Reinforced concrete pipe. Reinforced concrete pipe
shall be supplied in conformance with ASTM Specification C-76, Wall
B. Joints shall be of the compression-type II.[1]
B.
Corrugated metal pipe. All pipe shall be coated inside
and outside. Joints shall be made with connecting bands and rubber
gaskets to ensure tight joints. Thickness gauges shall be dependent
on the load conditions, except that 16-gauge shall be the minimum
allowable thickness.
A.
Catch basins shall be constructed per the detail of
masonry brick conforming to ASTM C-32, with mortar consisting of one
part portland cement to 1 1/2 parts sand.
B.
Precast catch basins shall also be considered upon
request to the Commissioner of Public Works.
C.
Catch basin leads shall be ten-inch, fully coated
and perforated corrugated metal pipe, 14-gauge with bands and gaskets.
Manhole ladders or steps shall be provided in
all sanitary and storm manholes and shall be constructed of one of
the following materials:
A.
Sanitary manhole frames and covers. Sanitary manhole
frames and covers shall be round Neenah R-1726 or Woodward M-138,
or an approved equal. The word "Sanitary" shall be cast into the top
of the cover. The inside diameter for clearance shall be a minimum
of 23 inches.
B.
Storm manhole frames and grates. Storm manhole frames
and grates shall have a minimum clear opening of 23 inches and shall
be Neenah 1728 or Woodward M-138 with vented lids, or an approved
equal.
C.
Catch basin frames and grates. Catch basin frames
and grates shall be Neenah R-3205 or Woodward W-447, or an approved
equal, for concrete gutter installation, with a minimum finished width
of 16 inches of clear opening. The frames and grates for granite curbing
installation shall be Neenah 3251, or an approved equal. Area frames
and grates shall be Neenah 3210A standard grate.
All materials and methods of installation shall
conform to either the Monroe County Water Authority or the Sea Breeze
and Vicinity Water District specifications for the applicable service
area.
B.
Samples from each two truckloads of concrete delivered
and placed on the site shall be taken and tested. Results of these
tests shall be submitted to the town. After placement and curing,
the surface shall be sealed with two coats of Koppers concrete sealer,
or an approved equal.
C.
Curbing (where required). Stone curb shall be an approved
granite from acceptable sources. Granite shall be of the Rockport
Grey granite type, or an approved equal, and shall conform to New
York State Department of Transportation item No. 714, Type S. Each
stone shall have a width of five inches, a minimum length of three
feet and a depth of from 17 inches to 19 inches.
A.
Base course, The base course shall consist of 12 inches
of clean run-of-bank gravel in two six-inch lifts conforming to New
York State Department of Transportation Item No. 304-2.02, Type 2
gravel or nine inches of crusher-run Dolomite stone conforming to
New York State Department of Transportation Item No. 304-2.02, Type
2, crusher run stone, in two lifts, 4 1/2 inches each. Before
placing the base course, the contractor shall receive the approval
of the Commissioner of Public Works for the quality of the material
and the condition of the subbase.
B.
Binder course. The binder course shall consist of
asphaltic concrete conforming to New York State Department of Transportation
Item No. 403.13, Type 3.
C.
Surface course. The surface course shall consist of
asphaltic concrete conforming to New York State Department of Transportation
Item No. 403.1901, Type 7F.
A.
The mention of apparatus, articles or materials by
name and such specific description of the same, as is made herein,
is intended to convey to the contractor's understanding the degree
of excellence required. The Town Engineer shall be the sole judge
of the qualifications of the offerings and will determine all questions
regarding the conformance of any offer with the specifications.
B.
The contractor will furnish the exact equipment called
for in the plans and specifications, unless the contractor files with
the town the name and complete description of each article which he
or she proposes to substitute, if the substitution is approved by
the Town Engineer.
