A. 
A hydraulic design report prepared by a licensed engineer, containing design information for all highway drainage structures, storm sewers and channels, must be submitted to the Town Engineer and Town Superintendent of Highways. This report should contain the basic design data required to arrive at each drainage structure size, such as design frequency, flow rate, grade, velocity, area and method used determining the waterway size. A consideration should also be given to anticipated (if any) future development and any urbanization of the area. Drainage design must be based on a minimum twenty-five-year storm.
B. 
There should be enough information shown on plans and profile to properly construct all the required drainage facilities. The type and size of culvert, end treatments of the inlet and outlet, the gage of metal pipe or class of concrete pipe, the invert elevation of the inlet and outlet, the ditch and channel section, gutters, the channel protection and alignment of ditches are some of the information required on plan and profiles.
A. 
The developer shall dedicate to the Town by recordable instrument all easements as shown on the plat.
B. 
All municipal drainage easements must have a minimum width of 20 feet and shall include the right in perpetuity to enter upon said property for the purpose of installing, maintaining, and repairing the ditches and pipes as placed in such easement. Stormwater drainage may be enclosed in pipes or in open ditches as approved by the Town Superintendent of Highways, and all easements shall contain a provision providing for the right to install underground pipes and open ditches and to discharge stormwater therein. The developer shall also install in said easements pipe or open ditch of a size sufficient to provide for present and future runoff. It shall also be accessible by equipment from the highway.
[Amended 11-24-2008 by L.L. No. 4-2008]
C. 
Where it is proposed that stormwater be drained from the highway or from other lands of the developer to the perimeter of the developer's property, easements shall be provided in recordable form and free and clear of all liens from the adjoining owners permitting the discharge of stormwater drainage onto such adjoining lands.
D. 
The developer shall provide an attorney's certificate of title indicating that the above-mentioned easements and rights to discharge surface water are free and clear of all liens.
A. 
Storm drain and culvert pipe may be fully bituminous-coated corrugated steel or reinforced concrete or an approved equivalent with a minimum diameter of 15 inches.
B. 
Steel pipe, pipe arches and end sections shall conform to Section 707 of the current Standard Specifications of the State of New York, Department of Transportation, with the following exception: All collars or connecting bands shall be 12 inches wide and shall be furnished with bolts six inches long. All collars shall be equally lapped.
C. 
Reinforced concrete pipe shall conform to Section 706 of the current Standard Specifications of the State of New York, Department of Transportation.
D. 
The height of the fill and pipe classes shall be designed to meet the minimum requirements of H-20 Highway Loading.
A. 
Whenever a drain pipe begins or ends in an open ditch, pond or stream, the inlet and outlet ends shall be designed to protect embankments and channels and to preserve the hydraulic efficiency of the pipe.
B. 
The following end treatments shall be used for drainage pipes:
(1) 
Prefabricated end sections.
(2) 
Headwall and wingwalls with or without concrete apron. (See Figure 7.[1])
[1]
Editor's Note: Figure 7 is located at the end of this chapter in Appendix B.
(3) 
Beveled pipe ends.
C. 
Prefabricated end sections shall be of similar material and construction to the pipe. End sections shall be connected to the pipe in the same manner as pipe sections are connected.
A. 
Underdrains may be a perforated-metal or porous-pipe type and placed in the trenches and surrounded by material which is both pervious to water and capable of protecting the pipe from infiltration by the surrounding soil.(See Figure 8A.[1])
[1]
Editor's Note: Figure 8A is located at the end of this chapter in Appendix B.
B. 
Underdrains must be sloped positively to an outlet such as a drainage channel or a closed drainage system.
C. 
Figures 8b and 12 of Appendix B[2] show the installation of underdrain for the purpose of draining of pavement sections. These figures may be modified to apply to specific conditions. However, criteria described below should be considered.
[2]
Editor's Note: Appendix B, containing Figures 8b and 12, is located at the end of this chapter.
D. 
The underdrains should be placed at the interface of the pavement and shoulder or curb and should intercept the water from the highest water-bearing layer of the pavement section.
Specifications and drawings on Figures 9, 10, 11, Appendix B,[1] show the minimum acceptable construction for typical catch basins and curb inlets. Whenever, in the opinion of the Town Superintendent, ground conditions or other circumstances require, larger or heavier materials, additional materials, reinforcing or other modifications and improvements in design and construction shall be made as directed by the Town Superintendent at any time prior to paving.
A. 
Location. Catch basins shall be constructed at all points of change of slope or alignment and at all junction points. Catch basins shall be located in the lows of sag vertical curves as necessary to prevent excess ponding. At no time shall catch basins be spaced farther apart than 400 feet on slopes less than 3%, 300 feet on slopes from 3% to 6% and 250 feet on slopes over 6% in steepness.
B. 
Excavation and construction.
(1) 
Holes for catch basin shall be excavated to a depth of nine inches below the bottom of the catch basin. The subbase shall be spread to a uniform compacted depth of nine inches over the entire area under the base. On this gravel base, an eight-inch thick slab of 1-2-4 mix portland cement concrete shall be placed. The slab shall extend four inches beyond the outside of the walls of the catch basin on every side and shall be smooth and level.
(2) 
To a maximum depth of 10 feet below the finished surface, the catch basin walls shall be constructed of solid concrete catch basin corner and stretcher blocks eight inches thick or cast-in place concrete.
(3) 
Below 10 feet from the finished surface, the catch basin walls shall be 12 inches thick and shall be constructed of concrete block or cast-in-place concrete. All hollows between blocks in each course shall be completely filled with mortar before the succeeding course is laid so that finished wall is solid.
(4) 
All blocks forming the catch basin walls shall be laid up with mortar composed of portland cement and mortar sand in the proportion of one to two.
(5) 
Approved precast catch basins may also be used.
(6) 
Inside dimensions of the catch basin shall remain constant from top to bottom and shall match the frame opening of the curb inlet to be used.
(7) 
Mortar used for filling vertical or inclined joints shall be of such consistency that will require rodding for placing. The mortar shall be rodded until it rises to the top and completely fills the joint. All joints in masonry units shall be full mortar joints not greater than 1/2 inch wide on the inside and outside.
(8) 
All construction and materials shall comply with Section 604 of the current Standard Specifications of the State of New York, Department of Transportation.
C. 
Installation of pipes.
(1) 
Concrete blocks around all pipes entering or leaving catch basins shall be cut to fit the contours of the pipes as closely as possible. Remaining interstices shall be solidly filled with mortar for the full thickness of the wall. Ends of all pipes shall be cut off flush with the inside surfaces of the catch basin walls and shall project outside a sufficient distance to allow for proper connection with adjoining pipe section.
(2) 
When the diameter of the effluent pipe is greater than that of an influent pipe, the elevation of the top of the influent pipe shall be no lower than the elevation of the top of the effluent pipe.
(3) 
When the diameter of the effluent pipe is the same as or smaller than that of an influent pipe, the elevation of the invert of the influent pipe shall be no lower than the elevation of the invert of the effluent pipe. In no case shall the top of any influent pipe be more than five feet above the invert of the effluent pipe.
D. 
Curb inlets.
(1) 
Catch basins shall be capped with curb inlets having a minimum frame opening of 24 inches by 36 inches of a type as designated by the Town Superintendent of Highways.
(2) 
Curb-type inlets shall be installed so that the top of the grating shall be flush with the finished grade, and the pavement shall be sloped toward the inlet as shown in Figure 9, Appendix B.[2]
[2]
Editor's Note: Appendix B, containing Figure 9, is located at the end of this chapter.
(3) 
Cast-iron frames and grates and cast-iron curb boxes shall conform to the current Standard Specifications of the State of New York, Department of Transportation, Division of Construction, and be designed to carry H-20 Highway Loading.
(4) 
Curb-front openings on all curb inlets shall have, centered in the opening, a solid horizontal bar to prevent the ingress of small children. This bar shall be part of the casting or solidly welded in place subsequent to manufacture.
E. 
Steps for catch basins. Catch basins having a depth greater than 48 inches from the finished surface to the top of the concrete base shall be provided with steps. Steps shall be of wrought iron having a minimum diameter of one inch, which shall be hot-bent to shape and hot-dipped galvanized after bending. They shall be solidly set in the masonry at the time of construction and shall extend all the way through the wall. The steps shall extend 4 1/2 inches inside the wall of the catch basin. The top step to the base steps shall be no more than 18 inches apart. Reinforced plastic steps meeting Section 725-02 of the Standard Specifications, State of New York, Department of Transportation, Construction Division, may be used in lieu thereof.
[1]
Editor's Note: Appendix B, containing Figures 9, 10 and 11, is located at the end of this chapter.
A. 
With the approval of the Town Superintendent of Highways and Town Engineer, open ditches for back lots and side slopes may be used in lieu of storm-drain pipes when the grade of the land transversed is flat or when it is desirable to drain and dry up the surrounding area.
B. 
In no case shall the grade of an open ditch exceed 6%. The following guidelines shall be used in treatment of these ditches:
(1) 
Up to 1%: seed and mulch.
(2) 
Up to 3 1/2%: jute mesh and seed.
(3) 
Up to 5%: sod.
(4) 
Over 5%: rip-rap or asphalt concrete.
C. 
Rip-rap, when called for, shall consist of field stone or rough, unhewn quarry stones as nearly cubical in form as is practicable, placed upon a slope not steeper than one to two and so laid that the weight of the large stones is carried by the soil and not by the stone adjacent. All stones shall weigh 50 to 150 pounds each and at least 60% of them shall weigh more than 100 pounds each.
D. 
The largest stones shall be placed first, roughly arranged and in close contact. The spaces between the larger stones shall be filled with spalls of suitable size.
E. 
Whenever a drain pipe enters an open ditch, the bottom and sides of the ditch shall be rip-rapped for a distance of at least 30 feet beyond the end of the pipe.
F. 
Roadside ditches over five-percent grade shall be paved with asphalt concrete in three-inch thickness.