Village of Muttontown, NY Site Plan Review

A key map at a scale of one inch equals 800 feet, showing clearly and accurately the location of the property in relation to the neighboring streets (streets shall show a double line).

The location, arrangements and materials of proposed means of access and egress, including sidewalks, curbs, driveways or other paved areas. Directional control signal and pavement markings shall be shown. Profiles indicating grading and cross sections showing width of roadway, location and width of sidewalks and location and size of water and sewer lines shall be shown. Any proposed direct pedestrian connection to public parking lots or structures shall also be shown, including handicap ramps at corners.

The location, direction, height, power and time of use for any proposed outdoor lighting or public address system.

The location, height and size of any freestanding pipe.

Any proposed screening and other landscaping, including types and locations of proposed street trees and other trees, shrubs or fences, etc.

Site plans for individual sites, residential and nonresidential, are to show the method of drainage using dry wells, drainage reserve areas or a recharge basin for a positive system utilizing Nassau County-type catch basins, manholes and connecting pipe. The proposed design for the site should be in agreement with the approved subdivision site plan.

The site plan or an accompanying landscaping plan must show all proposed and existing landscaping on the premises, in compliance with the minimum site landscaping standards.

[Added 9-8-2003 by L.L. No. 5-2003[2]]

[2]

Editor's Note: This local law also renumbered former Subsections P, Q, and R as R, S and T, respectively.

The site plan must show all existing and proposed easements.

Any positive drainage system or structures in the area which will be utilized by direct connection or for emergency overflow are to be shown. The agency having jurisdiction over the system or structure (county, town, Village, etc.) is to be indicated and approval is to be obtained from that agency.

Any other data deemed by the Village of Muttontown to be necessary to determine the adequacy of the site plan for the proposed development.

§ 144-5 Minimum standards and criteria for all uses.

Drainage standards.

All stormwater runoff storage criteria are minimum standards. Depending on specific site conditions, the Village Engineer may require that additional storage be provided above those standards set herein. All dry wells must be brought to grade with a minimum two-foot-diameter, cast-iron cover.

All interconnecting piping between drainage structures must be rigid pipe with a minimum ten-inch diameter. Roof leaders can be piped only with a rigid four-inch-diameter (minimum) pipe.

All dry wells must be a minimum of 10 feet clear from all property lines and 20 feet clear from building foundations. If the size of the lot, along with other zoning requirements for the building setback limits, does not allow the location of a dry well as mentioned above, then:

The developer's engineer may submit a letter to the Village Engineer with an original seal and signature indicating that a lesser distance to the building will not have an adverse effect on the building, and the reasons for this determination.

In no case should the minimum distance from the building be less than 10 feet.

The Village Engineer shall have the authority to either accept or reject any request based on a review of the subject matter.

Roof drains and gutters.

Whenever they are required, roof dry wells shall be provided having a storage capacity for a minimum two inches of rainfall and 100% runoff. They shall be constructed in accordance with the Village of Muttontown standards (see dry well detail).[1]

[1]

Editor's Note: The dry well (diffusion well) detail is included as an attachment to this chapter.

Gutters are required on all buildings. The following criteria are to be met:

For any hip-roofed house: five inches wide.

For gable roofs: four inches wide.

Minimum slope: 1/16 inch per foot.

(d)

Leaders shall not be located at any corner of the house, patio, walkway or driveway where there is or might be a drainage problem.

Roof water is not to be discharged into flower beds or planting areas next to (adjoining) any foundation. Window wells should be installed as necessary so as to provide adequate drainage away from the window and foundation.

When dry wells are not required, roof leaders with elbow shall be discharged onto concrete splash blocks which are adequately designed to carry stormwater away from the foundation and disperse it so as to prevent soil erosion.

Drainage for driveways and patios.

When a dry well is required for a driveway, it is to be sized to provide sufficient minimum storage capacity for a two-inch rainfall and 100% runoff from the paved area.

For any patio or other impervious backyard area over 500 square feet in size, dry wells may be required. The well is to be sized and located to provide sufficient storage capacity for a two-inch rainfall and 100% runoff from the impervious area.

Dry wells must have a minimum of a two-foot diameter grate or solid, cast-iron cover.

Lawn or yard drains.

Lawn or yard drains shall be provided if stormwater runoff onto adjoining lands is, or could cause, a problem. Drains should have a minimum of a two-foot-diameter grate.

Lawn or yard drains may be utilized for or be interconnected with driveway drainage.

Lawn or yard dry wells in accordance with the detail shall be located into an acceptable permeable soil to provide storage capacity for a two-inch rainfall and a minimum runoff coefficient of 30%.

Recharge basins or drainage reserve areas or dry well systems.

When recharge basins, drainage reserve areas or dry well systems are utilized in drainage systems for site plans, they are to be designed, detailed and constructed in accordance with the minimum standard criteria of the Nassau County Department of Public Works.

A recharge basin or drainage reserve area may be required for all applications for property in excess of 5.0 acres.

For recharge basins, drainage reserve areas and designated dry well systems listed above, the following minimum Nassau County criteria may be applied by the Village:

Five-inch-rainfall retention capacity with an overflow.

Eight-inch-rainfall retention capacity without an overflow.

One-hundred-percent runoff for impervious areas.

(d)

Minimum of 30% percent runoff for landscaped areas and natural wooded or undisturbed areas.

Drainage in parking fields.

Dry wells shall be provided for stormwater runoff.

Separate wells for roof drains are to be provided where feasible. Wells in the parking area may possibly be utilized for roof drainage when approved by the Village Engineer.

Provide diffusion wells eight feet minimum in diameter with a cone to provide sufficient storage capacity for two-inch rainfall and runoff factors of 1.00 (100%) for pavement and a minimum runoff coefficient of 0.30 (30%) for grassed and landscaped areas and areas with natural vegetation. Any group of wells is to be connected in series with a ten-inch-diameter pipe (minimum pipe size).

A cone is required for all diffusion wells in parking fields. Where impractical to provide a cone, a road slab and one solid section may be substituted.

A cast-iron casting with solid cover or grate at grade, as required, is to be provided for all dry wells in parking field areas.

(6)

The minimum clearance between adjacent wells shall be 10 feet between side walls or 1 1/2 times the effective depth, whichever is greater. Maximum required separation is 20 feet.

Driveways and private roadways.

Driveways and/or private roadways shall have a slope of not more than 10% pitched away from the structure and 8% pitched towards the structure. Where a driveway is pitched towards the structure, the driveway shall be swaled with the low point a minimum of eight feet away from the structure and a minimum of 0.3 foot below the garage floor. Drainage structures shall be provided as required to drain the low point of the driveway swale.

Areas and spaces designed for parking shall have a slope of not more than 5%.

Driveway drains may be utilized for or be interconnected with lawn or yard drains.

Drainage must be provided for driveways and parking areas in excess of 500 square feet. Dry wells shall be sized as a minimum to provide sufficient storage capacity for a two-inch rainfall and 100% runoff. In the event that a recharge or retention basin and positive drainage system has been installed in the roadway of a new subdivision, driveways may be discharged into this facility, providing the facility has been designed to accept this runoff.

Grading.

Front yard is to slope out and down to the sidewalk and/or curbline of the street.

Minimum slope of lawns is 1%.

Any undisturbed sloping areas which are outside the grading limit lines and are already stabilized and left undisturbed are to remain as is. No additional runoff is to be directed into this area from the newly constructed areas.

Grading of lots for areas that are disturbed or regraded:

Maximum slope, cut area: one vertical to two horizontal.

Maximum slope, fill area: one vertical to three horizontal.

Water is to be prevented from flowing over the top of slopes by berming and/or regrading or, if necessary, by the installation of drainage structures above the slope.

(d)

Lines with elevations indicating top and bottom of slope are to be shown.

(e)

Use retaining walls wherever the proper slope would encroach upon adjacent property.

(f)

Tree wells may be required whenever grade changes may adversely affect a tree.

Whenever backyards or portions of lots are not to be regraded but left in their natural state, grading limit lines are to be indicated on the site plan.

Minimum site landscaping. The applicant must provide the minimum landscaping on all sites as follows:

[Added 9-8-2003 by L.L. No. 5-2003[2]]

Ground cover consisting of topsoil and a full stand of grass over all disturbed areas.

Minimum foundation planting so as to be aesthetically pleasing from the mad and adjoining properties.

Driveway must be completed with an approved surface material.

[2]

Editor's Note: This local law also renumbered Subsections I through L as J through M, respectively.

Retaining walls.

A permit is required for all retaining walls not incorporated in a building permit application for another improvement.

A permit is not required for any wall less than 24 inches (two feet) high. Timber retaining walls which are greater then 24 inches (two feet) but less than or equal to 48 inches (four feet) can be constructed as a minimum in accordance with the typical Village of Muttontown detail.[3]

[3]

Editor's Note: The timber retaining wall detail diagram is included as an attachment to this chapter.

Any wall higher than 48 inches (four feet) is to be designed by a professional engineer or registered architect duly licensed by the State of New York. This shall include all types of walls (railroad ties, concrete, mortared brick, etc.).

Elevations.

First floor or first level of habitable use shall be a minimum of 18 inches above any part of any front yard street elevation, except where most or all of a lot is below or slopes down from the grade of the adjoining street.

Garage floors are to be 12 inches above any part of the adjoining street to which the driveway leads, except underground or depressed garages or where there are special conditions.

In floodplain areas, minimum elevations as stipulated in federal regulations for floodplain areas or areas subject to flooding are to be held.

All wood construction, including but not limited to sills, girders, joists, sheathing, studs and shingles, shall be a minimum of eight inches above the external finished grade.

Abnormal soil conditions. For lots and/or areas with impervious or abnormal soil conditions (i.e., hardpan, clay or perched water problems), where dry wells cannot be used, the overall site plan shall be submitted indicating how the lot and general area are to be sloped and drained, using swales, spot elevations, deep diffusion wells where feasible, etc. The scale of this overall plan shall not be less than one inch equals 50 feet.

Quality of materials. The quality of all materials, including but not limited to soil, stone blend, recycled concrete, asphalt, concrete, drainage structures, connecting pipes, metal castings and timber, shall be the responsibility of the applicant.

Note. "Acceptable permeable soil" is soil with an absorptive capacity of at least two gallons per square foot per day. Full-rate course, granular soil has permeability of four gallons per square foot per day.

§ 144-6 Control of stormwater runoff.

Residential areas.

Stormwater runoff is to flow away from all sides of the foundation and garage area.

Where surface stormwater is concerned, a plot may be graded, pitched or swaled to the street as long as the existing or new drainage facilities in the street can adequately accept the additional stormwater flow.

Surface stormwater runoff from graded areas shall not be diverted onto adjoining property or cause any erosion and damage to adjoining property or sidewalk areas. Whenever backyards or portions of the site are not to be regraded but left in their natural state, grading limit lines are to be indicated on the site plan.

Where roof stormwater is concerned, stormwater shall be collected by dry wells or directed toward roadways with adequate existing drainage facilities.

Any subsurface or perched water which may require drainage facilities must be indicated, and complete engineering details of methods used to keep cellars and basements reasonably dry shall be submitted. Data on subsurface groundwater shall be submitted, including the source method (test holes, borings, etc.) and date of collection of information shown. The applicant is responsible for determining the subsurface conditions.

(6)

Test holes may be required for an individual site if adequate soil information does not exist.

(7)

Stormwater runoff should not be permitted to flow directly into tidal waterways or freshwater wetlands.

Economic district.

Stormwater runoff is to flow away from all sides of the foundation. For any basement ramps or below-grade loading areas, drainage structures are to be provided having a storage capacity for an eight-inch rainfall and 100% runoff.

Roof drainage systems must be kept separate from parking area drainage systems and must be brought to grade with solid, cast-iron covers.

Stormwater runoff shall not be directed or diverted onto adjoining lands.

The drainage system for the entire complex (building, parking fields, etc.) is to be designed to be self-contained, using dry wells or a recharge basin. The drainage system is to be sized to adequately handle all stormwater runoff from the area being developed. Dry wells shall be interconnected to create a system or systems wherever practicable. Piping shall be located in the top full section of the dry well (minimum pipe size 10 inches). Approved material for piping for residential and commercial is RCP, cast and ductile iron, PVC Schedule 80 or SDR 35 and rigid corrugated plastic pipe with smooth walls, PVC pipe to have a minimum cover of four feet.

(6)

Pavement requirements for parking fields.

For commercial and industrial areas and areas of heavy trucking or high traffic concentration, the minimum pavement design to be constructed on suitable subbase material which is at least 12 inches deep shall be five inches compacted thickness of stone blend base or recycled concrete, two inches compacted thickness of asphalt binder and one inch compacted thickness of asphaltic concrete wearing course (NC Type I-A mix).