Town of Union, NY Design Standards

All materials utilized in the work shall be new and of the best grade on the market in their respective classes. Seconds or rejects will not be accepted. All work shall be executed in a thorough, substantial and workmanlike manner by a sufficient number of competent mechanics skilled in their respective trades. The specifications shall be interpreted to require first-class work and materials, and alternate materials or methods will be accepted if approved, in writing, by the Town Engineer.

The subdivider shall be responsible for repairs and maintenance of work due to defective materials and workmanship, including those necessitated by settlement of embankments or backfilled trenches for one year from the date of acceptance by the Town. The Subdivision Inspector shall notify the subdivider of such defective material and/or workmanship.

Reference specifications. When reference is made to a specification or standard for material, equipment and workmanship, the referenced shall mean the current edition of that specification or standard. Except as modified herein, the referenced specification or standard shall be considered a part of the Town of Union standards.

Materials testing.

Upon request by the Subdivision Inspector, the subdivider shall submit samples for laboratory inspection at the subdivider's expense or shall submit certificates from the manufacturer that the material conforms to specifications, as to grade and class of material.

Concrete. The subdivider shall pay for compression test cylinders of the concrete used in construction. The cylinders shall be made and tested by an approved commercial testing laboratory. Each load of concrete, regardless of quantity, shall have a test cylinder made, tested and reported. A copy of all dated reports of the test results shall be furnished to the Subdivision Inspector. All test results shall be identified by job name, date sample was taken, date test occurred, slump of concrete and precise location of the placed concrete. Any concrete which fails to conform to the specification requirements shall be removed and replaced at the subdivider’s expense.

[Amended 12-2-2009 by L.L. No. 15-2009]

Parks, playgrounds, and recreation areas.

[Added 11-20-2001 by L.L. No. 8-2001]

It is the policy of the Town of Union to provide an option for development standards to secure adequate land or financial resources for the long-term goal of providing high quality parks, playgrounds, and recreational areas for Town residents.

The Planning Board shall evaluate each subdivision application to determine whether a proper case exists for requiring that a park or parks be suitably located for playgrounds or other recreational purposes within the Town. Such findings shall include an evaluation of the present and anticipated future needs for park and recreational facilities in the Town based on projected population growth to which the particular subdivision plat will contribute.

In cases where the Planning Board determines that a park or parks of adequate size cannot be properly located in the subdivision plat or is otherwise not practical due to the size, topography, or location of the proposed subdivision, or if the Planning Board determines that additional parkland in the immediate vicinity of the proposed subdivision is unnecessary, the Planning Board may waive the requirement that the subdivision plat show land for such purposes and instead require a cash payment. The amount of said payment shall be determined by resolution of the Town Board. Any such cash payment shall be dedicated exclusively for park, playground, or other recreational capital improvement purposes as authorized by New York State Town Law § 277. Said cash payment shall be paid in full prior to the signature of the final plans by the Chairman of the Planning Board.

§ 181-22 Streets.

Principles for residential streets.

Street and pedestrian circulation patterns should be compatible with the objectives and policies established by the Future Land Use and Transportation Plan.

The street layout should minimize overall length and width of streets in order to lower construction and maintenance costs.

Through traffic on local streets should be avoided.

Local streets and cul-de-sac should provide direct access to residential units. Subcollectors may provide direct access to higher density residential units such as Townhouses or apartment clusters, may also be used as scenic drives and to locate minor retail and service facilities. Collector streets are suitable for locating neighborhood or community shopping areas and service facilities, as well as providing access for schools and multifamily dwelling units.

Major elements of the street system should be used to define and buffer different land use areas, thus enhancing their identity.

Street layouts should be planned to avoid excessive runoff concentrations.

Pedestrian, bicycle and vehicular traffic should be separated wherever feasible.

Sufficient rights-of-way should be provided for future road widening.

(9)

Development of road frontage in a linear manner should be controlled to avoid conflict with future road widening and interior land development.

(10)

Access points to major highways, thoroughfares and arterial streets should be limited in number, given special design considerations and, whenever possible, located where other features are not competing for driver attention.

(11)

Paths and sidewalks should connect predetermined destinations.

(12)

All dwellings shall be accessible to emergency and service vehicles.

Street classification design standard.

A street is primarily a public way for purposes of vehicular traffic and includes the entire area within the right-of-way. The street, secondarily, serves pedestrian traffic and usually accommodates public utility features within the right-of-way or on adjacent easements. The improvement or development of streets is based on a functional classification which is part of the Town's Future Land Use and Transportation Plan.

In the design of residential subdivisions, arterials, arterial connectors, collectors, subcollectors and local streets will be included. In most subdivisions, however, only collectors, subcollectors and local streets are involved. The street classification design standard is shown in Table I.[1]

Editor's Note: Table I, Street Classification Design Standard, is included at the end of this chapter.

Cul-de-sac standards. Dead-end streets shall terminate in a cul-de-sac conforming to these specifications:

Minimum right-of-way radii: 60 feet.

Minimum pavement radii, measured from face of curb to face of curb or from edge of pavement to edge of pavement: 50 feet.

No obstructions or island shall be placed within a cul-de-sac.

Intersection standards.

Within 40 feet of an intersection, the maximum grade on all streets shall be limited to 11/2%.

Intersections on curves should be avoided.

Large corner radii should be avoided.

Four-way intersections should be avoided in order to control traffic speed.

Oblique intersections should be avoided to assure pedestrian and vehicular visibility.

Streets shall be laid out so as to intersect as nearly as possible at right angles, and no streets shall intersect any other street at less than 80°.

A distance of at least 125 feet shall be maintained between offset intersections.

Subcollector or local street openings into collector streets shall, in general, be at least 300 feet apart.

Street layout and alignment.

Decisions regarding street layout should result from an evaluation of a variety of factors, including topography, soil characteristics, geologic conditions, drainage patterns, potential runoff quantities, length and character of streets, types and locations of abutting land uses and the purpose of the individual street.

The arrangement of streets in a subdivision shall provide for the continuation or appropriate projection of existing streets into surrounding areas.

Local streets shall be so aligned that their use by through traffic will be discouraged.

In general, subdivisions containing 20 lots or more should have at least two street connections with existing public streets or streets on an approved subdivision plat.

Block dimensions should be wide enough to accommodate two lots in depth and generally not more than 12 times the minimum lot width required in the applicable zoning district in length. In long blocks, the Planning Board may require the reservation of an easement through the block to accommodate utilities, drainage facilities or pedestrian traffic.

Where a parcel is subdivided into lots substantially larger than the minimum size required in the zoning district in which a subdivision is located, the Planning Board may require that streets and lots be laid out so as to allow for the location and opening of future streets and/or the logical further subdivision.

The street plan of a proposed subdivision shall bear a logical relationship to the topography of the property, and all streets shall be arranged so as to obtain as many building lots as possible at or above the grade of the streets.

Reserve strips. Reserve strips controlling access to streets shall be prohibited except when their control is placed under the Town under conditions approved by the Planning Board and Town Attorney.

(9)

Marginal access streets. Where a subdivision abuts or contains an existing or proposed arterial street, the Planning Board may require marginal access streets and controlled access points, reverse frontage with screen planting contained in a non-access reservation along the rear property line, deep lots with rear service access or other treatments as may be necessary for adequate protection of residential property and to afford a separation of through and local traffic.

(10)

Continuation of streets into adjacent properties.

The arrangement of streets shall provide for their continuation between adjacent properties where such continuation is determined to be necessary for proper traffic movement, effective fire protection, efficient provision of utilities, snow removal and other services, and/or where such continuation is in accordance with the Town's Future Land Use and Transportation Plan and its Official Map. Alternatively, if a street continuation is not determined to be warranted by the circumstances, would jeopardize the public safety and welfare or would result in unsafe traffic conditions, the Planning Board shall require such street to be terminated short of the boundary lines of the subdivision.

Where a continuation of a street beyond the boundaries of a subdivision is warranted, but the adjacent property is undeveloped and the street must dead end temporarily, the Planning Board shall require that the right-of-way and all improvements be extended to the property line. A temporary circular turnaround of a minimum of 50 feet in radius shall be provided on all temporary dead-end streets, provided that the temporary dead-end street provides access to building lots. A notation shall be placed on the plat that land outside the normal street right-of-way shall revert to abutting property owners upon continuation of the street.

(11)

Right-of-way for widening or realignment. Where the subdivision includes or borders on an existing street and additional land is required for realignment or widening of such street as indicated by the Town's Future Land Use and Transportation Plan, Official Map or otherwise determined by the Planning Board to be necessary, such land shall be marked on the subdivision plat "Reserved for Street Widening (or Realignment) Purposes." Land reserved for realignment or widening purposes shall not be counted in satisfying the bulk requirements of Chapter 205, Zoning.

(12)

In general, street lines within a block deflecting from each other at any one point by more than 10° shall be connected with a curve. The outer street boundary line shall always be parallel to the inner street boundary.

Cross sections.

Pavement shall be centered in the right-of-way and crowned so that the crown at the center line of the pavement is level with the top of curbs or six inches higher than the edges of the pavement if there are no curbs.

Where curbs are installed, the finish grade shall slope up from the tops of curb to a minimum distance of two feet at a rate of 1/4 inch per foot.

Where curbs are not installed, the finish grade shall slope down from the edges of the pavement at a rate of 3/4 inch per foot to form a shoulder with a minimum width of four feet.

Ditches or grassed swales shall be installed between the outside edge of the shoulder and the right-of-way line where curbs and gutters are not installed.

The provision of sidewalks should be a response to existing or potential need. If the Planning Board decides that sidewalks will be required on some or all streets within a subdivision, they shall be constructed with the outside edge of the sidewalk placed on the outside edge of the right-of-way line. Additional sidewalk shall be constructed at street corners for access to the roadway and shall have handicap ramps. Walks shall be five feet wide and shall slope toward the top of curb at a rate of 1/4 inch per foot.

Side slopes of embankments adjacent to the right-of-way shall not exceed two horizontal to one vertical. If slopes in excess of this are required in order to avoid the right-of-way lines, retaining walls shall be installed.

Guide rails shall be constructed following the criteria for guide rail installations as established by the New York State Department of Transportation in the current Highway Design Manual, Volume 1. Actual field conditions may warrant additional guide rail which shall be installed prior to Town acceptance, when so directed by the Town Engineer or Town Highway Superintendent.

Ridged perforated polyvinyl chloride (PVC) underdrain to control groundwater and/or drain the pavement subbase shall be required and installed where necessary, as determined by the Engineer or the Town Highway Superintendent. When, in actual construction, groundwater seepage is found which, in the opinion of the Engineer or the Town Highway Superintendent, will be injurious to the roadway, the subdivider shall install underdrain as directed.

[Amended 12-2-2009 by L.L. No. 15-2009]

(9)

Curbs and gutters. In general, curbs and gutters are required on all new streets within a subdivision. Subdivisions in agricultural districts may not be required to have curbs and gutters when conditions permit adequate drainage and the roadway base will not be adversely affected. The decision to waive the requirements for curb and gutters shall be with the Planning Board with the concurrence of the Commissioner of Public Works.

Driveway access.

Lots shall be laid out so the driveways have access to the street upon which they abut which carries or is intended to carry the lesser amount of traffic.

Driveways located on collector and arterial streets shall be designed so that cars will enter the road facing traffic.

Sight distance.

Visibility for traffic safety shall be provided, by excavation if necessary, within the triangles formed by the outside boundaries of intersecting right-of-way lines and a diagonal line connecting points in each right-of-way line, the points being 25 feet from the intersection of the outside boundaries of right-of-way lines.

Right-of-way landscaping and screen plantings, where required, should be selected according to low maintenance as well as vehicular and pedestrian traffic visibility needs.

Street names. Street names shall be selected by the prospective subdivider, subject to the approval of the Planning Board. Proposed street names shall be included on the preliminary plan. Subdividers shall be encouraged to consider the character of the neighborhood and nature of street naming in the general vicinity. Proposed street names shall be substantially different so as not to be confused in sound or in spelling with existing street names in the Town and, where practical, in the villages, except that streets that join or are in alignment with streets of an abutting or neighboring property shall bear the same name. Proposed street names should not bear the same name exclusive of the suffix, e.g., Forest Street, Forest Avenue, Forest Drive, etc.

§ 181-23 Easements.

In areas where permanent improvements are to be located in or on land that is not or will not be publicly owned, permanent easements shall be required. The easements shall:

Have a minimum width of 20 feet, except where such easement is contiguous to a street right-of-way, it shall have a minimum width of 10 feet.

Provide usable access to a public way.

Be in a form approved by the Town Attorney.

Run continuously with the land and can be released only at the discretion of the Town Board.

§ 181-24 Utilities.

Principles for design. Included in this section are sanitary sewers, water distribution systems, storm drainage facilities and streetlighting.

General principles.

Sanitary sewer and water and storm drainage systems and streetlighting should be designed to reduce capital, maintenance and environmental costs to the Town.

All existing lines within a system should be reasonably utilized before being extended.

Responsibility to accommodate potential upland development. Utilities shall be designed and constructed to accommodate potential upland development whether inside or outside the subdivision, which would feed into the proposed utility system. The size of the proposed system's piping shall be based on the reasonable expected development permitted by Chapter 205, Zoning, which may occur during the life of the system, about 30 years. All stormwater control systems shall accommodate potential runoff from the entire upstream drainage area which drains into the subdivision. The design and size of the facilities shall be based on anticipated runoff from a ten-year storm.

Responsibility for impact on lowland development. The subdivider shall study the effect of each subdivision on existing lowland development and utility systems. Where it is anticipated that additional flows will overload an existing 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 provisions have been made for the improvement of said condition.

Utilities in street. All utilities within the subdivision shall be placed underground. The Planning Board may require that underground utilities be placed in the street right-of-way between the paved roadway and street line to simplify location and repair of lines when they require attention. The subdivider shall install underground service connections to the right-of-way line of each lot within the subdivision for such required utilities before the street is completed.

Sanitary sewer system principles.

Where feasible, sanitary sewer systems should be gravity flow.

Sanitary sewer piping, structures and placement should be designed so that they can be maintained by the Town's equipment.

Water system principles. Development of multiple private water systems should be discouraged.

Storm drainage system principles.

The best available technology shall be used to minimize off-site stormwater runoff, increase on-site infiltration, encourage natural filtration functions, simulate natural drainage systems and minimize off-site discharge of pollutants to ground- and surface water.

Stormwater discharge from a subdivision shall not exceed the discharge that emanated from the undeveloped property prior to its development as a subdivision.

Storm runoff in new developments should not be permitted to increase discharge directly into inadequate downstream storm systems during time of peak runoff.

Natural overland flows as well as open channel and swale routings should be the preferred alignments for major components of a residential drainage system.

Open channels and swales should harmonize with the natural features of the site and be closely related to individual building lots.

The design of permanent and temporary ponding and/or storage areas should be an integral part of the overall development planning process.

(g)

Design of permanent storage facilities should consider safety, appearance, recreation use and effective, economical maintenance operations as well as the primary storage function.

(h)

Encourage the design of storm drainage systems which will minimize potential erosion and sedimentation problems.

(i)

Erosion from stormwater runoff should be minimized by appropriate design within the system, but erosion control or prevention should be achieved at the source if downstream sedimentation problems are to be avoided.

(j)

Energy dissipators and other outfall protection should be designed and installed where enclosed drains discharge onto erodible soils.

(k)

Enclosed components of stormwater runoff systems should help manage stormwater, not just dispose of it.

(l)

The use of enclosed components should be minimized to the extent consistent with the ability of existing natural systems to accommodate storm runoff and the degree to which the public will accept and act responsibly toward open channels.

Streetlighting principles.

Streetlighting in residential subdivisions primarily is intended to serve motorists, not pedestrian or house security needs.

In subdivisions where nonresidential uses are planned, especially where such use(s) may involve pedestrian activity, such as a park or school, additional streetlighting for pedestrian traffic may be required.

Location of utilities.

Only one utility line shall be installed in the same trench, except for power, telephone and cable television lines.

Sanitary sewers shall be placed along the center line of the street with house connections extending to the right-of-way lines.

Storm sewers lines shall be placed at a distance of 10 feet from the center line. Connections shall extend to catch basins placed along the curblines or to inlets placed along the ditch lines.

Water mains shall be placed at a distance of 10 feet from the center line with service connections extending to the right-of-way lines.

All water mains and services shall have a minimum depth of cover of five feet.

Sanitary sewer lines shall be deep enough to service basements and shall have a minimum cover of three feet. Care shall be taken in establishing the grade of sewers to ensure that the lateral connections thereto do not intercept other lines of water mains.

Fire hydrants shall be placed 21/2 feet beyond the face of curbs or seven feet beyond the edge of pavement where curbs are not installed. The height of the hydrant shall be a minimum of 18 inches from finished grade to the center of the steamer cap. They shall be spaced at the distance required by the appropriate municipal water works, generally 500 feet apart.

Sanitary sewers.

Design standards.

Sanitary sewers shall be designed for the estimated ultimate tributary population. Stormwater, roof drainage and groundwater shall be excluded from sanitary sewers and house connections. In general, sewers shall be sufficiently deep to serve basements. Any deviation from this rule must be clearly noted on the subdivision plat and approved, in writing, by all governing authorities.

Sanitary sewer systems shall be designed on the basis of an average daily per capita flow of sewage of not less than 100 gallons per day. Lateral sewers shall be designed to carry a peak flow of 400 gallons per capita per day. Trunk sewers shall be designed to carry a peak flow of 250 gallons per capita per day.

No sanitary sewer shall be less than eight inches in diameter. All sanitary sewers shall be designed and constructed to give mean velocities, when flowing full, of not less than two feet per second, based on Kutter's formula using an "n" value of 0.013. Where velocities greater than 15 feet per second are attained, special provisions shall be made to protect against displacement by erosion and shock. Where the velocity is in excess of 10 feet per second or the grade is greater than 15%, ductile iron pipe (DIP) shall be used.

All sanitary sewer systems shall be designed and constructed in accordance with the requirements of the Broome County Health Department, the New York State Department of Environmental Conservation and the Great Lakes - Upper Mississippi River Board of State Sanitary Engineers Recommended Standards for Sewage Works (GLUMRB).

In subdivisions with 20 lots or fewer, where the sanitary sewer system cannot be a gravity flow system, a system of individual grinder pumps and a pressurized trunk line shall be used. The grinder pump shall be owned and maintained by the individual homeowner. The grinder pump shall meet the Town standards.

Manholes. Manholes shall be installed at the end of each line, at all changes in grade, size or alignment, at all intersections and at intervals not exceeding 400 feet.

House connections (laterals).

Laterals shall be laid from wye branches placed in the sewer line to the street right-of-way line. A long sweep bend shall be used at the wye branch and the connection shall be laid on a straight grade such that the end of the connection is sufficiently deep to receive sewage from the basement. In no case shall the pipe be laid on a grade less than 1/4 inch per foot. All laterals must be laid straight and true to grade and alignment in a separate trench from all other utility trenches.

When a sanitary sewer lateral is constructed of different material than the trunk sewer line, the connection between them shall be made with an adaptor, approved by the Subdivision Inspector, which has been manufactured for connecting different pipe materials to each other.

A cleanout shall be provided at the property line. The end of the lateral, at the cleanout, shall be tightly stoppered in a manner approved by the Subdivision Inspector.

The location of all wyes at the main, as referenced to their distance from the manholes and all lateral cleanouts with ties and depths, shall be recorded on the Sanitary Sewer Utility Plan.

Pipe laying.

Sanitary sewers shall be laid to the line and grade indicated on the approved drawings so that the invert will be smooth and uniform. Pipe which is not true in vertical or horizontal alignment, or which shows any settlement after laying, shall be taken up and relaid at the subdivider's expense.

Pipe shall not be laid on frozen ground.

Any pipe damaged by handling or which is found to be defective in any respect is to be rejected.

Tests for sanitary sewers.

All sewers shall be tested for watertightness in the presence of the Subdivision Inspector and shall meet the requirements set forth below before final acceptance of the work. The subdivider shall furnish all necessary appliances and make the tests at his/her own expense.

A lamplight shall be clearly visible between manholes.

Immediately prior to all tests, the contractor shall determine the groundwater elevations and this data shall be recorded as part of the test information.

Localized or spurting leaks of any volume detected in sewers shall be permanently stopped.

The entire sewer line shall be tested by the low-pressure air method.

Should any leaks, defective joints or defective construction be found, they shall be corrected promptly, and should any defective pipes or fittings be discovered, they shall be removed and replaced with sound pipes or fittings in a satisfactory manner at the subdivider's expense.

Appurtenances. Sewage lift stations, disposal works and appurtenances shall be designed and constructed to afford a maximum of dependability and efficiency in operation and maintenance and shall be approved, in writing, by the Town Engineer. Two copies of as-built drawings of these facilities, together with all manuals and descriptive literature, shall be furnished to the Engineering Department before the facilities will be accepted by the Town.

Water distribution system.

All improvements shall be in compliance with Chapter 41, Town of Union Code, Water.

Capacity.

The water distribution system shall be designed to provide an average daily flow of 100 gallons per capita per day. The system shall be capable of supplying a maximum domestic flow equal to nine times the average daily flow while maintaining a minimum pressure of 35 pounds per square inch at the street level. Where such pressure cannot be reached at the street level, a pressure booster shall be placed in each house to increase the pressure to a minimum of 35 pounds per square inch at the first floor level. Provisions shall be made to prevent pressures from exceeding 100 pounds per square inch.

The water distribution system shall be capable of supplying a four-hour fire flow, in addition to a domestic flow, 11/2 times the average daily flow of 750 gallons per minute from a hydrant while maintaining a residual pressure of 10 pounds per square inch at the hydrant.

Water mains.

All water supply and distribution systems shall comply with the requirements of the Broome County Health Department, New York State Department of Environmental Conservation and the Endicott Municipal Water Works or the Johnson City Municipal Water Works or the Town of Union Water Department depending on the source of the water.

Water mains shall have a minimum diameter of eight inches, except six-inch mains may be allowed for minor distribution mains as approved, in writing, by the Town Engineer and the appropriate municipal waterworks.

The system shall be interconnected at all intersections and dead ends shall be avoided whenever possible. Where long runs are not interconnected at frequent intervals, the main shall have a minimum diameter of 12 inches. Waterlines that are not looped shall be provided with a cleanout hydrant at the end of the line.

Appurtenances. Booster pumping stations, storage facilities and other appurtenances to the distribution system shall be designed and constructed to afford a maximum of dependability and efficiency in operation and maintenance. Two copies of as-built drawings of these facilities, together with all manuals and descriptive data, shall be furnished to the Engineering Department before the facilities will be accepted by the Town.

Drainage facilities.

Design standards.

No stormwater runoff or natural drainage water shall be diverted as to overload existing drainage systems or create flooding or the need for additional drainage structures on other private properties or public lands without proper and approved provisions being made for alleviating these conditions.

Stormwater facilities consisting of side ditches, minor culverts, stormwater sewers and combinations thereof shall be designed to intercept and carry the maximum runoff from the tributary watershed during a ten-year frequency storm. The design for structures for major streams shall be based on an individual analysis utilizing the current accepted practices of the United States Department of Commerce, Bureau of Public Roads or the United States Department of Agriculture, Soil Conservation Service.

For design purposes, a ten-year frequency storm shall be considered to have the following intensity-duration relationship:

Maximum five-minute intensity is equal to 5.8 inches per hour.

Maximum ten-minute intensity is equal to 4.9 inches per hour.

Maximum fifteen-minute intensity is equal to 4.2 inches per hour.

[4]

Maximum twenty-minute intensity is equal to 3.7 inches per hour.

[5]

Maximum twenty-five-minute intensity is equal to 3.3 inches per hour.

[6]

Maximum thirty-minute intensity is equal to 2.9 inches per hour.

[7]

Maximum sixty-minute intensity is equal to 1.8 inches per hour.

Except for structures on major streams which may utilize other acceptable methods, runoff computations shall result in flows equal to those computed by the Rational Method, using a time of concentration and runoff factor in keeping with the local topography and Table II:

Table II Runoff Factors
	Runoff Factors/Land Slope
	Flat (0-5%)	Steep (over 5%)
Land Use
Residential	0.40	0.45
Light commercial	0.70	0.75
Large paved areas	0.80	0.90
Parks, woods, etc.	0.30	0.35

Weighted runoff factors shall be considered for composite areas.

The drainage systems shall provide for conveying the runoff to the nearest natural watercourse or storm sewer, in a manner approved by the Town Engineer.

(g)

The Manning formula shall be utilized for the design of stormwater pipes and ditches. The following coefficients of friction ("n") shall be used.

Concrete pipe: n = 0.013.

Corrugated steel pipe:

[a]

Fully paved: n = 0.013.

[b]

Paved invert:

[c]

Two-and-two-thirds-inch by one-half-inch corrugations: n = 0.024.

[d]

Three-inch by one-inch corrugations: n = 0.027.

[e]

Six-inch by two-inch corrugations: n = 0.032.

Earth ditches, seeded: n = 0.030.

[4]

Paved ditches, concrete or asphalt: n = 0.013.

[5]

Polyvinyl chloride (PVC) smooth interior: n=0.010.

[Added 12-2-2009 by L.L. No. 15-2009]

(h)

New York State Stormwater Management Design Manual, August 2003 (or latest version) shall be used as the standard for drainage plans to determine the size of water detention ponds for specific watershed areas. Copies of the design data shall be provided to the Engineering Department.

[Amended 12-2-2009 by L.L. No. 15-2009]

Side ditches.

Longitudinal ditches shall be placed on the high side of all streets, and on both sides of streets, where necessary, to intercept water entering the subgrade of the street.

Unpaved ditch sections shall have sufficient cross-sectional areas to maintain maximum runoff velocities below two feet per second to prevent scouring and erosion. Ditches shall be paved or riprapped and check dams shall be installed, where necessary, to maintain safe stream bed velocities. Protection shall be provided to prevent erosion at bends, beneath check dams and at culvert inlets and outlets where necessary.

Ditches shall have a minimum width at the bottom of the ditch of 12 inches, and side slopes not steeper than two horizontal to one vertical.

Culverts.

Culverts shall be installed to pass water collected in the ditches or flowing in a natural watercourse beneath the street. Headwater depths shall be considered in culvert design. Riprap shall be installed upstream and downstream of culverts as required to control erosion. Energy dissipators shall be constructed where necessary.

Culverts under streets shall extend from toe of slope to toe of slope and shall be set with a minimum of two-foot cover over the top of the pipe unless specifically waived, in writing, by the Town Engineer or the Town Highway Superintendent.

Culverts also shall be installed beneath driveways and access roads to carry water flowing in the side ditches. Culverts in side ditches shall be limited to 30 feet in length.

Culverts shall have a minimum diameter of 15 inches and shall be laid on a minimum grade of 0.5%. In general, the grade line shall coincide with the existing stream bed or ditch grade.

Culvert ends.

All culverts shall utilize pipe end sections at each end or poured concrete headwalls.

Reinforced concrete pipe end sections shall be precast units and corrugated steel pipe end sections shall be galvanized steel. All end sections shall conform to the standards of the New York State Department of Transportation.

On all pipe end sections 24 inches or larger, a poured concrete cutoff wall, a minimum thickness of 12 inches, shall be constructed to a minimum depth of 24 inches below the end section, for the full width of the flared end.

[4]

Concrete headwalls for culverts shall be constructed of poured concrete extending at least 12 inches above and 24 inches below the pipe. Concrete headwalls shall be at least 12 inches thick and as wide as the top of the ditch, but not less than three pipe diameters wide.

Stormwater sewers.

No stormwater sewer shall be less than 15 inches in diameter except that catch basin connections may be as small as 12 inches in diameter.

All storm sewer lines shall be designed and constructed to give mean velocities, when flowing full, of not less than three feet per second. Velocities over 15 feet per second shall be avoided by the use of drop manholes. When unavoidable, the pipe shall be anchored to prevent movement and the standard manhole designs indicated in the Standard Detail Drawings[1] shall be modified to adequately reinforce such structures against the increased forces.

Editor's Note: The Standard Detail Drawings are included at the end of this chapter.

Storm sewers shall be laid with a minimum of two feet of cover over the top of the pipe. However, catch basin connections, when constructed of corrugated steel pipe, may have a minimum of one foot of cover at the catch basin, when approved, in writing, by the Town Engineer.

Structures.

Manholes shall be installed at the end of each line, at all changes in grade, size or alignment, at all intersections and at intervals not exceeding 300 feet.

Catch basins shall be installed at all intersections and at intervals not exceeding 300 feet and shall be placed on both sides of the street, thereby maximizing the length of street draining into any catch basin to 300 feet.

All connections to stormwater sewers from catch basins shall be made at a manhole. The maximum distance between catch basin and manhole shall be 55 feet.

Streets ending in permanent culs-de-sac shall have storm sewer installed within the cul-de-sac.

Underdrain shall be installed behind the curb, where the adjoining lots grade toward the street and as determined by the Town Engineer. Any underground drains, i.e., footer, eaves, etc., draining toward the street shall be connected to the underdrain. The minimum diameter of the underdrain shall be six inches.

Stormwater sewers and culvert pipe materials.

Pipe used in storm sewer systems shall be reinforced concrete pipe except that corrugated steel pipe or polyvinyl chloride pipe (PVC), upon written approval by the Town Engineer, may be used to connect a catch basin to a manhole.

Pipe used for culverts shall be reinforced concrete pipe or, upon the written approval by the Town Engineer, corrugated steel pipe.

Pipe laying. All stormwater drainage systems shall be installed to the line and grade indicated on the approved drawings.

Testing. All storm sewer lines shall meet the following test in the presence of the Subdivision Inspector: A lamplight shall be clearly visible between manholes. Pipe which is not true in vertical or horizontal alignment or which shows any settlement after laying shall be taken up and relaid at the subdivider's expense.

Appurtenances. Pump stations, flap valves, sluice gates and appurtenances to stormwater drainage systems shall be designed and constructed to afford maximum public safety, dependability and efficiency in operation and maintenance. Two copies of as-built drawings of these facilities, together with all manuals and descriptive data, shall be furnished to the Engineering Department before the facilities will be accepted by the Town.

Streetlighting. Underground wiring for the streetlights, the light poles, light pole bases, heads and luminaries shall be provided by the subdivider. In general, the streetlights shall be located at street intersections and spaced at intervals of 500 feet. The location of said streetlights shall be approved by the Town. The type of streetlights shall meet Town of Union standards.

Fire call boxes. Subdivisions located in districts having fire call boxes shall be required to have fire call boxes, poles and the necessary underground wiring and connections provided by the subdivider. The need for and the location of the fire call boxes shall be determined by the appropriate fire company. The fire call boxes, poles and underground wiring shall meet Town of Union standards and the standards of the respective fire company.

Guide rails. In general, guide rails shall be corrugated beam or cable type construction. Box beam guide rail may be required and approved for specific cases. All materials and installation procedures shall comply with the Standards of the New York State Department of Transportation.

Retaining walls construction. Retaining walls shall be concrete gravity walls, reinforced concrete cantilever walls or steel bin type walls. Applicable New York State Transportation Standards shall be followed. The use of gabion construction shall be specifically approved, in writing, by the Town Engineer. When approved, applicable manufacturer's construction standards shall be followed. All walls or structures designed to retain earth fills shall be proportioned to withstand pressure as given by Rankine's formula, but no structure shall be designed for less than an equivalent fluid pressure of 30 pounds per cubic foot. When highway traffic can come within a distance from the top of the structure equal to 1/2 its height, the pressure shall have added to it a live load surcharge pressure equal to not less than two feet of earth.

Right-of-way monuments and property markers.

Placement. Lot corner monuments shall be placed at all lot corners, lot angles, points of curvature and points of tangency. Permanent monuments shall be placed at the corners of the boundaries of the original tract and at least two of said monuments remote from each other, on one side of each street in the proposed subdivision or subdivision phase. All monuments shall be placed by a licensed land surveyor.

Construction. Lot corner monuments shall be steel rods at least 1/2 inch in diameter and 24 inches in length. Permanent monuments shall be steel rods at least one inch in diameter and 24 inches in length and permanently set in concrete. Said monuments shall be shown "o" and "__" respectively on the subdivision plat sheet. Pipe will not be approved for monuments. The monuments shall be driven flush with the ground and marked with a two by two wooden guard stake. The steel rods used as lot corner monuments and permanent monuments shall have either a plastic or aluminum surveyor's cap pushed onto the iron. Before the street will be accepted for maintenance by the Town, all monuments must be placed. Any monuments which are disturbed or destroyed during construction shall be replaced by the subdivider, at his/her expense, prior to acceptance.

§ 181-25 Lots.

Lot dimensions and area. All lots shall meet the minimum area and lot size required by the zoning district in which it is located.

Arrangement. The arrangement of lots shall be such that there will be no foreseeable difficulties, for reasons of topography or other conditions, in locating a building on each lot and in providing access to buildings on such lots from an approved street.

Solar access. The arrangement of lots should be so oriented to the sun as to permit individual properties to use passive and/or active solar energy systems.

Side lot lines. Side lot lines should be substantially at right angles to straight street lines and radial to curved street lines.

Corner lots. Corner lots shall have sufficient width to provide an adequate building site within all requirements of Chapter 205, Zoning. Such corner lots shall have a minimum width equal to the minimum width required in the district plus the street setback requirement.

Double frontage lots. Double frontage lots should be avoided except where lots back up on an arterial or collector street. In such instances, vehicular and pedestrian access between the lot and the arterial or collector street is prohibited. Where topographic or other conditions render subdividing otherwise unreasonable, such double frontage lots shall have an additional depth as determined by the Planning Board in order to allow for a protective screen planting.

Lots abutting a watercourse, Lots abutting a watercourse, drainage way, channel or stream may be required to provide additional area to assure an acceptable building site.

Lots containing freshwater wetlands. Lots containing or located within 100 feet of a freshwater wetland as designated by the New York State Department of Environmental Conservation are subject to the review and hearing provisions of Chapter 125, Freshwater Wetlands.

Lots in floodway or floodplain districts. All structures or uses in the floodplain are subject to the floodplain provisions of Chapter 121, Flood Damage Prevention.

§ 181-26 Commercial/industrial areas.

In addition to the other requirements of this chapter, each subdivision of land reserved or laid out for commercial and/or industrial uses shall be subject to the following additional requirements:

The Planning Board may require additional street width to accommodate higher traffic flow and on-street parking.

Width and depth of properties shall be adequate to comply with the off-street parking and loading requirements of Chapter 205, Zoning.

The Planning Board may require the installation of plantings, walls, fences or other improvements that will assure a satisfactory buffer or protective screen.

§ 181-27 Grading and erosion control.

The following control measures shall be used for effective control of drainage, erosion and sedimentation:

The smallest practical area of land shall be exposed at any one time during construction.

When land is exposed during construction, the exposure should be kept to the shortest practical period of time.

Where necessary, temporary vegetation and/or mulching should be used to protect areas exposed during construction.

Sediment basins, debris basins, desilting basins and silt traps should be installed and maintained to remove sediment from runoff waters and protect land undergoing change.

Provisions should be made to effectively accommodate the increased runoff caused by changed soil and surface conditions during and after construction.

The permanent final vegetation and structures should be installed as soon as practical.

The development plan should be fitted to the topography and soils so as to create the least erosion possible.