Town of Clay, NY Private Sewage Disposal Systems

Individual sewage disposal systems or other means of private sewage disposal shall not be approved where a sanitary sewer is available within 100 feet of a building, as measured along normal location of street sewer. In case an individual sewage disposal system is one of the several such systems designed to serve contiguous lots of a proposed subdivision, such system shall not be approved if the sum total of the length of the street and other sewers required to connect without pumping with an existing sewer adequate as to the capacity and available for service is equal or less than 100 feet times the number of such lots.

Where sanitary sewers are not available and where sewer construction is impracticable in the foreseeable future, individual sewage disposal systems or other means of private sewage disposal shall be considered for approval in low-density residential areas. "Low-density" shall be construed to be such lots having a minimum surface area of 20,000 square feet, or greater if required by soil and topographic conditions, including provision for duplicate reserve areas for disposal field.

In those cases of tract developments where sewers are feasible and are likely to be built in a reasonable future, individual systems may be allowed on lots with a smaller area, if connection with the future street sewers is assured. Such cases of development in the areas other than low-density shall be dealt with on the basis of specific conditions, upon securing a special permit from the Zoning Board of Appeals following the procedure set forth in § 182-5.

Wells. Sanitary sewage or the effluent from any individual sewage disposal system shall not be discharged into any abandoned well or any well reaching into the ground water.

Maintenance. Septic tanks, seepage pits and disposal fields shall be maintained in a manner that will not create any nuisance or source of foulness due to seepage to the surface of the ground, or due to gas emission, nor become a source of pollution to any of the waters of the state.

§ 182-10 Location of various component parts.

Distances. The minimum distance for location of the various component parts of the disposal system shall comply with the following table.[1]

[1]

Editor's Note: The minimum distance table is included at the end of this chapter.

Soil. The disposal area shall be located and constructed in soil having adequate permeability, as determined in accordance with the provisions of § 182-16. The soil shall also provide proper support for each component of the system. In cases where fill becomes necessary, such fill shall be compacted or allowed to settle to the satisfaction of the Inspector.

Flooding. No part of the sewage disposal system shall be constructed in ground subject to surface flooding or where ground water may interfere with satisfactory percolation of sewage.

Area reserved for sewage disposal. The area to be used for sewage disposal shall be selected and maintained so that it is free from encroachments by driveways, accessory buildings, additions to the main building, and trees or shrubbery whose roots may cause clogging of any part of the system.

Drainage. The ground surface over and adjacent to disposal areas shall have sufficient slope to prevent the accumulation of surface or subsurface water.

§ 182-11 Sewer connection of septic tank with house plumbing.

Size. The sewer connection shall be of such size to serve the connected fixtures as required by the State Uniform Fire Prevention and Building Code and any pertinent regulations but in no case less than four inches.[1]

[1]

Editor's Note: Amended at time of adoption of Code (see Ch. 1, General Provisions, Art. I).

Material. Sewer connection shall be constructed of cast iron, vitrified tile, concrete, asbestos cement or of other type approved in writing by the Inspector provided cast iron shall be used where the building sewer will be located under driveways.

Joints. All pipe joints in the sewer connection or any other part of the system not part of the disposal area shall be made watertight and protected against damage by roots.

Foundations. The sewer connection shall be laid on a firm foundation satisfactory to the Inspector.

Grade. The building sewer shall have a minimum grade of not less than 1/4 inch per foot unless otherwise authorized by the Inspector.

Alignment and grade. The sewer connection shall be laid in a continuous grade and as nearly as possible in a straight line. Drop manholes may be installed if found necessary. Horizontal bends, where required, shall not be greater than 45_.

Ventilation. The building sewer shall be ventilated through the vent stack or main vent, and no trap shall be installed in the building sewer.

Depth. The depth of the invert of the sewer connection shall be determined by the elevation of the disposal area.

§ 182-12 Septic tanks.

Capacities. Septic tanks shall have the following minimum capacities when serving single-family dwelling units shown below. Expansion attics shall be considered as additional bedrooms.

	Number of Bedrooms	Liquid Capacity of Tank (gallons)
	2 or fewer	750
	3	900
	4	1,000
	For each additional bedroom, add	250

Construction.

Septic tanks shall be watertight and constructed of sound and durable materials not subject to excessive corrosion, decay, frost damage or to cracking or buckling due to settlement or backfillings. Covers shall be designed and constructed so as not to be damaged by any load which may be placed on them.

Poured-in-place concrete tanks shall not be less than six inches in thickness.

The base of sectional prefabricated or block constructed tanks shall be cast in one piece and of sufficient size to extend beyond the outer side of the side and end walls of the tank. Such tanks shall not be placed or constructed until 48 hours after the base has been poured. The inside and outside walls of cinder or concrete block tanks shall be waterproofed in a manner acceptable to the Inspector.

Foundations. Septic tanks shall be constructed on a foundation satisfactory to the Inspector.

Materials.

Septic tanks may be constructed of the following:

(a)

Poured-in-place concrete.

(b)

Precast reinforced concrete.

(c)

Heavy weight concrete block or equal.

(d)

Cinder block or equal.

(e)

Prefabricated metal.

(f)

Material approved by the Inspector.

Prefabricated metal tanks shall conform to the Commercial Standards 177-51 of the U.S. Department of Commerce, and shall bear the Underwriters Laboratories label.

Length. The liquid depth of the tank or a compartment thereof shall be not less than 30 inches nor more than 60 inches.

Diameter of circular tanks. No tank or compartment thereof shall have an inside horizontal dimension less than 24 inches.

Inlets and outlets.

Inlet and outlet connections of each tank or compartment shall be arranged so as to obtain effective retention of scum and sludge. An inlet baffle is not required when the tank is provided with a vented pipe tee, not less than four inches in diameter with the bottom opening extending at least six inches below the surface of the liquid, or as required by Commercial Standard 177-51 for metal tanks. The invert elevation of the inlet shall be not less than one inch (preferably three inches) above the invert elevation of the tank outlet or the outlet of the first compartment. The inverts of the inlets and outlets of subsequent compartments may be at the same level.

Outlet connections of the tank and of each compartment thereof shall be provided with a tee not less than four inches in diameter or a durable baffle equivalent in size. They shall be permanently fastened in place with the bottom opening extending to the depth of about 40% of the liquid depth for vertical tanks. For horizontal, cylindrical tanks, this should be reduced to 35%. Inlet tees or baffles where used and outlet tees or baffles shall extend to not less than one inch below the inside top of the tank.

Scum storage. The space between the liquid surface and the top of the scum retaining device on the outlet shall be not less than 15% of the total required liquid capacity.

Access openings. Each compartment shall be provided with an access opening at a depth not greater than 18 inches below finished grade. In single compartment tanks, the access opening shall be located over the inlet. In multiple compartment tanks, access openings shall be located over each inlet and outlet. Access to each compartment of the tank shall be by means of a sixteen-inch minimum size manhole or a removable cover. The inlet and outlet devices shall be accessible by properly placed manholes, handholes or by an easily removable cover.

§ 182-13 Dosing tanks.

Dosing tanks shall be provided where there are over 500 linear feet of open-jointed or perforated distribution lines.

§ 182-14 Distribution box.

General. A distribution box shall be installed between septic tanks and disposal fields or seepage pits. If only one seepage pit is used, no distribution box is required.

Connecting pipe. The pipe connecting the septic tank and distribution box shall conform to the provisions of § 182-11.

Construction. Distribution boxes shall be watertight, constructed of concrete or other durable material and laid on a firm foundation. They shall be designed to accommodate the necessary distribution lines leading therefrom and to provide equal distribution to such lines by means of baffles or other acceptable methods.

Access. Distribution boxes shall be provided with a means of access. In the case of small boxes, this may be a removable top. If the top of the distribution box is more than 18 inches below finished grade, the access opening shall be extended to between 18 inches and 12 inches below finished grade.

Distribution lines. Each distribution line shall be connected separately to the distribution box. The inverts of all outlet lines shall be rigidly set at the same level. The invert of the inlet shall be at least one inch above the invert of the outlet.

§ 182-15 Disposal areas.

General. The disposal area is the entire area used for underground dispersion of the liquid portion of sewage. It may consist of a sewage pit or a disposal field or combination thereof. The disposal area to be provided shall be determined by the results of percolation tests performed in accordance with the provisions of § 182-16, type or soil available and drainage conditions. Greater area may be required by the Inspector in case of shale or other subsurface rock.

Type of disposal area permitted. The disposal area shall consist of a disposal field constructed in accordance with § 182-17 or seepage pit constructed in accordance with § 182-20 or a combination thereof.

Location. Disposal areas shall be located as designated in § 182-10.

§ 182-16 Determination of soil characteristics.

Generally. The quality of soil available as percolation media shall be determined from the results of tests as herein prescribed, type of underlying soil, drainage conditions or by other related data that may be required by the Inspector.

Percolation tests and reports.

At least one percolation test shall be performed at the site of each disposal area. More than one test will be required where the soil structure may vary or large disposal areas are required. Preliminary tests for large tracts involving more than one disposal system may be made in the amount of one per acre or as prescribed by the Inspector. In case grade of disposal area is to be lowered more than one foot below the original surface grade in actual construction, a second percolation test may be required subsequent to grading of the lot.

Percolation tests shall be performed as prescribed in this section under supervision of a licensed professional engineer or qualified sanitarian.

Percolation tests shall not be made in test holes which have been allowed to remain open to the atmosphere for periods over three days or in frozen ground. Tests shall not be made in filled ground unless the soil has been compacted or allowed to settle to the satisfaction of the Inspector.

Percolation tests shall be performed in accordance with the following procedure:

(a)

Type of test hole. Dig or bore a hole, with horizontal dimensions of from four inches to 12 inches and vertical sides to the depth of the proposed absorption trench. (Test hole for a seepage pit is made at the midpoint depth of the pit.)

(b)

Preparation of test hole. Carefully scratch the bottom and sides of the hole with a knife blade or sharp-pointed instrument, in order to remove any smeared soil surfaces and to provide a natural soil interface into which water may percolate. Remove all loose materials from the hole. Add two inches of coarse sand or fine gravel to protect the bottom from scouring and sediment.

(c)

Saturation of the soil. Fill the hole with clear water to a minimum depth of 12 inches over sand or gravel. Keep water in the hole for at least four hours, refilling it if necessary. Determine the percolation rate 24 hours after water is first added to the hole.

(d)

Percolation rate measurement. With the exception of sandy soils, percolation rate measurements shall be made on the day following the procedure described under Subsection B(4)(c), above.

[1]

If water remains in the test hole after the overnight swelling period, adjust the depth to approximately six inches over the gravel. From a fixed reference point, measure the drop in water level over a thirty-minute period. This drop is used to calculate the percolation rate.

[2]

If no water remains in the hole after the overnight swelling period, add clear water to bring the depth of water in the hole to approximately six inches over the gravel. From a fixed reference point, measure the drop in water level at approximately thirty-minute intervals for four hours, refilling six inches over the gravel as necessary. The drop that occurs during the final thirty-minute period is used to calculate the percolation rate. The drops during prior periods provide information for possible modification of the procedure to suit local circumstances.

[3]

In sandy soils (or other soils in which the first six inches of water seeps away in less than 30 minutes, after the overnight swelling period), the time interval between measurements shall be taken as 10 minutes and the test run for one hour. The drop that occurs during the final 10 minutes is used to calculate the percolation rate.

(5)

Reports shall be furnished to the Inspector signed and certified by the licensed professional engineer or sanitarian indicating the results of each percolation test in minutes per inch, the date of the test, effect of recent rain or lack of rain, the apparent moisture of the soil prior to the testing, the depth to ground water when encountered, number of preliminary tests made to determine apparent saturation, the type or types of soil encountered, together with the thickness of each layer and all other factors affecting percolation test results. Such report shall be accompanied by a map showing exact locations of test holes.

Subsoil and ground water determination.

The Inspector may require additional information relative to soil structure and ground water elevations adjacent to or below the proposed disposal area.

The number of test borings or pits shall be as specified by the Inspector.

The depth of test borings or pits shall be five feet below the bottom of the proposed seepage pit or eight feet below the bottom of the proposed disposal field or to solid rock when encountered within the foregoing depth requirements.

Reports of the type, nature and depth of the soils found and the depth to ground water shall be furnished to the Inspector. Samples of soil removed shall be carefully preserved when required by the Inspector.

§ 182-17 Disposal fields.

Generally. A disposal field is used for dispersion of the liquid portion of sewage into the ground as near the surface as possible. A disposal field may consist of disposal trenches, a disposal bed or combination of both. Disposal fields may consist of disposal trenches as described in § 182-18 or a disposal bed as described in § 182-19.

Standard for disposal field construction. Disposal trenches shall be constructed in accordance with § 182-18 and disposal beds in accordance with § 182-19.

Filter material. Filter material shall cover the distribution lines and extend the full width of the trench or bed, shall not be less than six inches deep beneath the bottom of the distribution line, and shall extend at least two inches above the top of the line and as further required in Subsection C of § 182-18. The filter material shall be washed gravel, crushed stone, slag, or clean bank-run gravel ranging in size from 1/2 to 21/2 inches, free of fines, dust, ashes or clay. The filter material shall be covered by untreated paper or by a two-inch layer of hay or straw as the laying of the distribution lines progress. Use of waterproof paper for this purpose is prohibited.

Distribution lines. Distribution lines shall be constructed true to line and grade with open joints or perforations, except that at least one tight joint at each bend or other fitting shall be provided to prevent slippage. Agricultural tile may either be laid on grade boards securely nailed to stakes driven into the undisturbed earth forming the trench bottom or carefully laid at the required slope on the gravel bed under the tile. Openings between joints shall be 1/8 inch to 1/2 inch with the upper half of the joint covered with asphalt-treated paper not less than three inches wide. Perforated tile, bituminized fiber or asbestos cement or equally adequate pipe may be used provided a sufficient number of clear openings extending through the entire thickness of the pipe are available to permit complete distribution of sewage into the disposal area. Any section of pipe laid with tight joints, except fittings as required above, shall not be considered in determining the percolating area.

Depth. Distribution lines shall not be laid at depths of greater than 24 inches below finished grade unless authorized by the Inspector. Where more suitable soil is located at two to five feet below the ground surface the bottom of the trench may be deepened into the aforesaid soil provided said excavations are filled with filter material as provided in Subsection C of this section. The top of distribution lines shall not be less than nine inches below finished ground surface.

Excavation. Excavation for disposal beds or trenches may be made by machinery provided that the adjacent soil will not be compacted and the provisions of Subsection H of § 182-9 are met. No excavating machinery shall be permitted in the excavation. When an excavation is carried below the required depth, it shall be brought up to the proper elevation with filter material as specified in Subsection C of this section.

Water table. Disposal fields shall not be constructed in areas, where the maximum ground water elevation may be less than four feet below the bottom of the trench or bed unless experience has indicated that disposal fields being of similar nature and size and having equal volume of sewage have functioned satisfactorily for a reasonable period of time.

Fill. When disposal fields are built up by fill to a depth of two feet or more, the area of such fill shall extend at least 20 feet beyond the limits of the disposal field and the fill shall be of earth having a percolation value at least equal to that of the ground in which the disposal field is constructed.

Impervious formations. Disposal fields shall not be constructed over impervious ground formations where such formations are less than 10 feet below the finished ground surface unless experience has indicated that disposal fields in the immediate area, being of similar nature and size and handling equal volumes of sewage, have functioned satisfactorily for a reasonable period of time.

Sloping ground. When distribution lines must be laid at different elevations in order to meet the slope requirements of Subsection C of § 182-18, the change in elevations shall be accomplished by use of distribution boxes as required by § 182-14.

Backfill. Backfill over disposal trenches or beds shall not be tamped and no grading machinery shall be permitted to pass over the area. The surface may be rolled by a hand-type roller for the purpose of completing a lawn.

§ 182-18 Disposal trenches.

Percolating area. The percolating area of disposal trenches shall be considered as the total bottom area of the disposal trench system in square feet, except that any section of trench containing pipe laid with tight joints other than fittings as required in Subsection D of § 182-17 shall not be considered in determining the percolating area.

Minimum percolating area. The minimum required percolating area per bedroom shall be determined from the following table, provided that in no event shall the total bottom trench area be less than 140 square feet for each dwelling unit:

	Percolation Rate - Time Required For Water To Fall One Inch (minutes)	Required Absorption Area Per Bedroom,¹ Standard Trench² and Seepage Pits³ (square feet)
	1 or less	70
	2	85
	3	100
	4	115
	5	125
	10	165
	15	190
	30⁴	250
	45⁴	300
	60^4,5	330

NOTES:
¹ In every case, sufficient area should be provided for at least two bedrooms.
² Absorption area for standard trenches is figured as trench bottom area.
³ Absorption area for seepage pits is figured as effective sidewall area beneath the inlet.
⁴ Unsuitable for seepage pits if over 30 minutes.
⁵ Unsuitable for leaching systems if over 60 minutes.

Disposal trench construction. Disposal trenches shall be constructed in accordance with the following table:

Minimum lines per field: two.

Maximum length per line: 100 feet (preferably 60 feet).

Minimum diameter of distribution lines: four inches.

Preferred slope of distribution lines: two inches to four inches in 100 feet.

(5)

Maximum slope of distribution lines: six inches in 100 feet.

(6)

Maximum depth of trench: 30 inches.

(7)

Minimum width of trench bottom: 18 inches.

(8)

Minimum distance between distribution lines:

	18-inch trench	6 feet 5 inches, center to center
	24-inch trench	7 feet, center to center
	36-inch trench	8 feet, center to center

(9)

Minimum depth of stone under distribution lines: six inches.

(10)

Minimum width of trench:

	Percolation test
	1 to 4 minutes	18 inches
	5 to 9 minutes	24 inches
	10 to 60 minutes	36 inches

§ 182-19 Disposal beds.

General. Disposal beds shall consist of an area in which the entire earth contents have been removed, filter material as required in Subsection C of § 182-17 placed in the excavation, and distribution lines installed at a depth not greater than 24 inches below finished grade.

Percolating area. The percolating area of disposal beds shall be considered as the total bottom area in square feet.

Minimum percolating area. The minimum required percolating area per bedroom shall be determined by adding 20% to the total bottom area of disposal trenches required under provisions of § 182-18 for various percolation tests, provided that in no event shall the total bottom area be less than 168 square feet for each dwelling unit.

Disposal bed construction. Disposal beds shall be constructed in accordance with the table in Subsection C of § 182-18, excepting that minimum distance from edge of bed to nearest distribution line shall be three feet and that a minimum of 12 inches of filtering material shall be provided under the distribution lines.

§ 182-20 Seepage pits.

General. Seepage pits shall be used only when preceded by a septic tank except as otherwise provided in Subsection D of § 182-9. They may be permitted in lieu of or as a supplement to a disposal field where conditions warrant their use. Because of the health hazard involved in the possible pollution of underground water supplies, seepage pits shall not be permitted if water supply is from a well on the lot unless special permission is granted by Inspector.

Percolating area. The percolating area shall be considered as the previous bottom and side areas of the excavation below the elevation of the inlet. The probable efficiency of the pit shall be judged on the basis of percolation tests performed at depths required by § 182-16.

Minimum percolating area (individual dwellings). The minimum required percolating area shall be determined from the table in Subsection B of § 182-18, provided that in no event shall the total percolating area be less than 140 square feet for each dwelling unit.

Construction. Seepage pits shall be constructed within an excavation affording adequate working space and shall be constructed of stone, brick, cinder or concrete block, of similar material laid dry with open joints where the permeable strata has been penetrated, except that if the seepage pit is not of circular construction or if the surrounding ground is subject to cave-in, all horizontal joints shall be mortared in such a manner as to prevent structural failure. All joints above the inlet shall be made watertight.

Backfill.

The space between the excavation and seepage pit wall shall be backfilled with at least six inches of coarse gravel or filter material prescribed in Subsection C of § 182-17. Where cinder or concrete blocks are laid with core openings exposed, the space between the excavation and seepage pit wall shall be backfilled with at least six inches of two-and-one-half inch crushed stone or similar material.

Backfill above the permeable strata and inlet shall be thoroughly compacted by hand or mechanical tamping methods. The use of heavy machinery or water for this purpose is prohibited.

Covers. If the upper layers of masonry are not drawn in to provide a smaller diameter opening than the diameter of the pit, a reinforced concrete cover shall be provided.

Bottom. The bottom of the pit shall be filled with coarse gravel to a depth of one foot unless the bottom is in a gravel or sand formation. The bottom shall not be less than four feet above the maximum ground water elevation unless special permission is granted by the Inspector.

Impervious foundations. The bottom of any seepage pit shall be at least eight feet above any impervious formation unless experience has indicated that seepage pits in the immediate area being of similar nature and size and handling equal volumes of seepage, have functioned satisfactorily for a reasonable period of time.

§ 182-21 Dry wells.

Dry well permitted. A dry well may be utilized to receive the drainage from roofs, basements, or areaways, provided its installation will not interfere with the operation of the individual sewage disposal system.

Location. Dry wells shall be located as required in Subsection A of § 182-10.

§ 182-22 Administration, permits and certificates of compliance.

Permits. Individual sewage disposal systems shall not be located or constructed until the Inspector has issued a permit for such location or construction of each individual sewage disposal system. Permits shall not be issued until:

Application. A properly executed application has been submitted on a form supplied by the Inspector. Such application shall include a sketch showing the property to be served, the location of sewage disposal facilities proposed, the number of bedrooms, including any expansion attic, for single-family dwellings or the estimated daily sewage flow as determined under the provisions of this chapter for establishments other than single-family dwellings, the location of any source of water supply on the same or adjacent premises and other data as required by the provisions of this chapter or the Inspector.

Percolation tests. The results of one or more percolation tests have been made, submitted to, and found to be satisfactory by the Inspector. Such tests shall be conducted in accordance with the provisions of this chapter and in a manner satisfactory to the Inspector.

Site inspection. The Inspector has determined that the disposal area will not be subject to surface or subsurface flooding; all surface and subsurface water will be drained away from such area and that all grading of the premises, except that requiring the use of hand tools, has been completed.

Examination of application. The Inspector has determined that the design of the individual sewage disposal system or systems as proposed is in compliance with this chapter.

Revised plans. Revision of plans of proposed individual sewage disposal systems shall be approved only with the written consent of the Inspector. The Inspector may require such revision of plans as he deems necessary if conditions found prior to or during construction warrant such change in order to obtain compliance with the provisions of this chapter.

Construction inspections. The Inspector shall make sufficient inspections during the course of construction of any individual sewage disposal system to determine if the soil beneath the septic tank, distribution box or seepage pit is adequate to support such structure; if excavation for the disposal area or seepage pits discloses a type of soil that will confirm the results of percolation tests and that the system has been constructed in accordance with the provisions of this chapter. The Inspector may require additional percolation tests in the actual disposal area or at the stratum to be used for sewage disposal.

Backfilling. Individual sewage disposal systems or parts thereof shall not be covered until inspected by the Inspector and permission has been granted for such backfill. Any part of the disposal system which has been covered without such permission shall be uncovered upon the order of the Inspector.

Certificate of compliance.

Individual sewage disposal systems shall not be placed in service until a certificate has been issued by the Inspector indicating that the said disposal system has been located and constructed in compliance with this chapter.