Subsurface Sewage Treatment Systems.
15 RCNY § 18-38
in effect§ 18-38 Subsurface Sewage Treatment Systems.
(a) Minimum Requirements for new subsurface sewage treatment systems.
(1) The design, treatment, construction, maintenance and operation of new subsurface sewage treatment systems, and the plans therefor, require the review and approval of the Department, provided that the requirements of this section shall not apply to subsurface sewage treatment systems necessary for an agricultural activity that are designed, provide treatment and are constructed, maintained and operated in compliance with State and Federal law.
(2) All new individual sewage treatment systems shall comply with the requirements of 10 NYCRR Part 75 and Appendix 75-A except where a local government or agency has enacted, or these rules and regulations specify, more stringent standards, in which case, the more stringent standards shall apply.
(3) All new intermediate sized sewage treatment systems shall comply with the requirements set forth in New York State Design Standards for Intermediate Sized Wastewater Treatment Systems, New York State Department of Environmental Conservation (2014), except where a local government or agency has enacted, or these rules and regulations specify, more stringent standards, in which case, the more stringent standards shall apply.
(i) As a condition of approval the Department may require evidence of financial security prior to construction, from any owner or operator of a new intermediate sized sewage treatment system or a substantial alteration or modification to an existing intermediate sized sewage treatment system. Such financial security shall consist of a bond, or an equivalent guaranty, to be deposited with the Department, covering the full cost of the construction of such facility and an additional bond or an equivalent guaranty for the payment of labor and material furnished in the course of such construction. Upon completion of construction and payment of labor and materials, such bonds or other guaranties shall be released. Additionally, a bond or equivalent guaranty may be required for the maintenance and operation of the facility for a period of five years post-construction. No bond or guaranty is required where the owner or operator of such a facility is a village, town, county or city.
(4) No part of any absorption field for any new subsurface sewage treatment system shall be located within the limiting distance of 100 feet of a watercourse or wetland or 300 feet of a reservoir, reservoir stem or controlled lake. For a new conventional individual subsurface sewage treatment system or for a new Ulster County Fill System the Department may recommend a greater limiting distance from an absorption field to a watercourse, wetland, reservoir, reservoir stem or controlled lake.
(5) Raised systems, as described in 10 NYCRR Part 75 and Appendix 75-A, are allowed on undeveloped lots not located in a subdivision or on undeveloped residential lots located in a subdivision which was approved prior to the effective date of these rules and regulations, where site conditions are not suitable for a conventional system provided that:
(i) The system shall be located at least 250 feet from any watercourse or wetland and 500 feet from any reservoir, reservoir stem or controlled lake provided that the greater limiting distance for raised systems does not preclude construction on the subject lot or lots of the use proposed by the applicant, and further provided that the site conditions and the subsurface sewage treatment system comply with the other provisions of these rules and regulations and other applicable Federal, State and local laws, as cited in 15 RCNY § 18-38(a)(1); or
(ii) Raised systems which cannot meet the limiting distances set forth in subparagraph (i) due to size or location of the lot shall be located at the greatest limiting distance possible within the property lines and at least 100 feet from any watercourse or wetland and 300 feet from any reservoir, reservoir stem or controlled lake.
(6) Where a watershed county has adopted a subdivision code that allows a raised system, as described in 10 NYCRR Part 75 and Appendix 75-A, or where the New York State Department of Health approved such raised systems for use in subdivisions located in the watershed, such raised systems are allowed in subdivisions that are approved subsequent to the effective date of these rules and regulations, provided that no part of such systems shall be located within 250 feet of a watercourse or wetland or 500 feet of a reservoir, reservoir stem or controlled lake.
(7) Any approval of a subsurface sewage treatment system issued by the Department expires and is null and void unless construction is substantially completed such that the system is functioning as designed within five (5) years of the date of issuance for systems located within approved subdivisions, or within two (2) years of the date of issuance for all other subsurface sewage treatment systems. Following expiration of the approval, the plans for the subsurface sewage treatment system may be resubmitted to the Department for consideration for a new approval.
(b) Minimum requirements for alteration and modification, repair and remediation, and discontinuation of subsurface sewage treatment systems.
(1) All subsurface sewage treatment systems, which are operating in accordance with their Federal, State, and local approvals, but which do not comply with the requirements for new subsurface sewage treatment systems set forth in this section, shall be allowed to continue to operate.
(2) If the use of a subsurface sewage treatment system is, for any reason, subject to discontinuation for a period of five consecutive years or more, operation may resume if it comes into compliance with the standards for alterations or modifications of subsurface sewage treatment systems in accordance with 15 RCNY § 18-38(b)(4) below. If, however, the system cannot come into compliance with these standards, the use must permanently desist. The owner or operator bears the burden of proof for showing that there has been no discontinuation in the use of a subsurface sewage treatment system.
(3) Any proposed alteration or modification of any subsurface sewage treatment system requires the review and approval of the Department, except as provided in subparagraphs (i) through (iii) below.
(i) The volume, character, or strength of the flow to a subsurface sewage treatment system may be reduced without review and approval provided that such reduction does not cause any increase in the existing discharge or any increase in the potential for contamination to or degradation of the water supply from that discharge. If the reduction in the volume, character, or strength results from an alteration or modification of a system component, or the addition of a new system component (such as installation of a peat filter or aerobic treatment unit), then such alteration, modification, or addition requires review and approval of the Department, except that:
a. Any such review and approval shall be limited to the affected system component; and
b. No such review and approval is required where the alteration, modification, or addition of the system component is otherwise exempt from review under this section (such as the replacement of a septic tank with a larger tank of an appropriate size for the subsurface sewage treatment system).
(ii) Except as set forth in this subdivision, for an intermediate sized subsurface sewage treatment system that has a State Pollutant Discharge Elimination System (SPDES) permit, review and approval is not required for any proposed alteration or modification that does not deviate from the engineering design and site plan approved by the New York State Department of Environmental Conservation.
a. Review and approval by the Department is required if the alteration or modification requires a modification of the SPDES permit for the SSTS for any reason including, but not limited to:
i. the alteration or modification involves physical alteration or modification of the SSTS, or
ii. the alteration or modification results in the system receiving sewage that either exceeds the treatment system design flow, or has a strength or characteristic beyond the design capability of the treatment system.
b. If the Department has previously issued an approval for an intermediate sized subsurface sewage treatment system, review and approval by the Department is required for any alteration or modification that results in the system receiving sewage that either exceeds the design flow of the system as approved by the Department, or has a strength or characteristic beyond the design capability of the system as approved by the Department.
(iii) In the following circumstances, where an ancillary, non-residential use of a residence served by an individual subsurface sewage treatment system does not result in an increase in or change in the nature of the flow of sewage, the subsurface sewage treatment system shall not be considered an intermediate-sized sewage treatment system, nor shall such use require review and approval by the Department:
a. Where the residence is used to provide accommodations for transient lodgers and no food service is provided other than to overnight guests, unless such use requires a temporary residence permit pursuant to 10 NYCRR Subpart 7-1.
b. Where the individual residence is used for a home office or home business, provided that:
i. The individual who operates the home office or home business occupies the home as his or her primary or secondary residence;
ii. The home office or home business is of a type that is estimated to generate 50 gallons per day of water or less based on Table B-3 of the New York State Design Standards for Intermediate Sized Wastewater Treatment Systems, New York State Department of Environmental Conservation (2014); and
iii. The conversion does not involve an increase in the individual residence's number of bedrooms.
(4) Standards for Alterations or Modifications of Subsurface Sewage Treatment Systems.
(i) Any proposed alteration or modification of any subsurface sewage treatment system must be performed in accordance with the requirements applicable to new subsurface sewage treatment systems under this section.
(ii) Alterations or modifications of subsurface sewage treatment systems that cannot meet these requirements, due to site constraints, must be performed in accordance with the requirements applicable to new subsurface sewage treatment systems to the extent possible. Applications for proposed alterations or modifications of such subsurface sewage treatment systems must include the information described in 15 RCNY § 18-38(d)(4).
(iii) Standard of review. The department will authorize use of a subsurface sewage treatment system that has been subject to a period of discontinuation for five consecutive years or more, or a proposed alteration or modification of a subsurface sewage treatment system, if the applicant demonstrates that such use, alteration, or modification does not present a threat to public health or water quality as determined by the Department.
(5) If a subsurface sewage treatment system fails or needs remediation, the owner or operator of the subsurface sewage treatment system must comply with the following:
(i) Any proposed remediation of any part of a subsurface sewage treatment system shall require the prior review and approval of the Department, and if approved, shall be completed as soon as possible in accordance with a schedule approved by the Department;
(ii) Any proposed remediation of any part of a subsurface sewage treatment system shall be implemented, to the extent possible, in accordance with the design standards set forth in this section, and shall require the prior review and approval of the Department. However, if the Department determines, based upon the application submitted by the owner or operator of the subsurface sewage treatment system, that such system cannot comply with this section, the owner or operator of the subsurface sewage treatment system shall cooperate with the Department to determine the most suitable location and design for the system on the specific site. The Department may require the owner to agree to a regular schedule for the pump out of the septic tank or other remedial action, including the use of holding tanks, before the proposed remediation is approved by the Department and implemented; and
(iii) The provisions of this paragraph shall not apply to the routine repair and maintenance of a subsurface sewage treatment system, including, but not limited to, the pump out of a septic tank, the replacement of a septic tank, whether in kind or with a larger tank of an appropriate size for the subsurface sewage treatment system, the repair of a broken lateral, the leveling of a distribution box, or the removal of a blockage.
(6) Any approval issued by the Department to use a subsurface sewage treatment system following a discontinuation expires and is null and void unless any required enhancements are implemented and such use is commenced within one (1) year of the date of issuance or such longer period as the Department may authorize in writing. Following expiration of the approval, the plans for the subsurface sewage treatment system may be resubmitted to the Department for consideration for a new approval.
(7) Any approval of an alteration or modification of a subsurface sewage treatment system issued by the Department expires and is null and void unless any required enhancements are implemented within two (2) years of the date of issuance. Following expiration of the approval, the plans for the subsurface sewage treatment system may be resubmitted to the Department for consideration for a new approval.
(8) Any property owner may request that the Department review and approve a proposed use of a subsurface sewage treatment system by demonstrating that it is capable of treating a specified volume and type of wastewater flow. The proposal may include proposed enhancements to the system. A determination by the Department that the subsurface sewage treatment system complies with the standards applicable to new subsurface sewage treatment systems or, if it cannot come into compliance the standards applicable to alterations or modifications of subsurface sewage treatment systems to the extent possible pursuant to 15 RCNY § 18-38(b)(4), for the proposed use and volume, shall be binding upon the Department for five years following the date of the determination.
(c) Design, operation, treatment, and maintenance requirements.
(1) All subsurface sewage treatment systems shall be designed, operated and maintained to prevent the exposure of sewage to the surface of the ground or the discharge of sewage to ground- water.
(2) Limitations on certain systems in the watershed.
(i) Mound systems, galley systems, seepage pits, evaporation-transpiration (ET) and evaporation-transpiration absorption (ETA) systems are prohibited from use for subsurface sewage treatment systems installed in the watershed on or after June 30, 2002.
(ii) Drip and low profile dispersal systems, as described in New York State Design Standards for Intermediate Sized Wastewater Treatment Systems, New York State Department of Environmental Conservation (2014) are prohibited from use for subsurface sewage treatment systems installed in the watershed on or after September 25, 2019.
(iii) Sand filters are prohibited from use for individual sewage treatment systems in the watershed.
(iv) For new subsurface sewage treatment systems within the 60-day travel time, and for new subsurface sewage treatment systems that require State Pollutant Discharge Elimination System (SPDES) permits, trench length reductions will not be offered for use of any enhanced subsurface sewage treatment systems.
(v) No trench length reductions shall be granted for use of any open-bottom gravelless absorption system, as described in 10 NYCRR Appendix 75-A.8(c)(3)(i). One linear foot of a gravelless absorption system is equivalent to one linear foot of conventional (24" wide) absorption trench.
(3) An additional area of at least 100 percent of the primary absorption field shall be set aside as a reserve absorption field for any subsurface sewage treatment system.
(4) No part of any primary or reserve absorption field shall be built under pavement or other impervious surfaces, and pavement and other impervious surfaces shall not be built over such absorption fields after installation.
(5) At least one percolation test and at least one deep hole test must be performed in the primary absorption field. At least one percolation test and at least one deep hole test must be performed in the reserve absorption field. An applicant must notify the Department in writing at least seven (7) days prior to performance of such tests, and specify the location and the time of the tests. Such soils testing must be performed during normal business hours on weekdays other than legal holidays. At the option of the Department, a Department representative may witness such tests.
(6) Proposed sites with soil percolation rates faster than 3 minutes per inch or slower than 60 minutes per inch shall not be approved by the Department for locating a subsurface sewage treatment system.
(7) Whenever possible, gravity flow systems shall be used for subsurface sewage treatment systems. The use of electrically operated pumps shall require a chamber equipped with an alarm to indicate malfunction and any other safety features required by the Department to prevent sewage overflow. An intermediate sized sewage treatment system that uses electrically operated pumps is required to have either a backup pump or a backup storage tank capable of holding two days' flow. An individual sewage treatment system that uses electrically operated pumps shall have a backup storage tank capable of holding one day's flow.
(8) A reserve absorption field is intended to be left undisturbed to be used in the event that the primary absorption field fails in the future. If the reserve absorption field is used because the primary absorption field has failed, the owner should, but is not required to, identify a new reserve absorption field. If the reserve absorption field is used for purposes of expanding the subsurface sewage treatment system, a new reserve absorption field or Department-approved alternative must be identified.
(d) Application Requirements.
(1) An application for review and approval of any subsurface sewage treatment system shall include the following information:
(i) Soil investigation report including:
(a) percolation test results;
(b) deep hole test pit results or boring analysis indicating the depth of useable soil;
(c) indication of surface water or ledge rock observed;
(d) design rate of flow; and
(e) delineation of United States Department of Agriculture Soil Conservation Service soil type boundaries.
(ii) Building permit number and tax map number where available.
(iii) Four (4) sets of plans prepared by a design professional showing:
(a) site location, including distances to wells, watercourses, rock outcroppings, wetlands, controlled lakes and reservoirs, and any property boundaries within 10 feet of any subsurface sewage treatment system component;
(b) site/system plans, drawn to scale, with topography showing two-foot contour intervals;
(c) system profile;
(d) details of system components; and
(e) a report containing:
(1) a description of the project characteristics; and
(2) a detailing of the design process.
(2) An application for review and approval of an intermediate sized sewage treatment system shall include all of the information in paragraph (1) of subdivision (c) of this section, and additionally shall contain:
(i) An Environmental Assessment form and State Environmental Quality Review Act determination, if applicable; and
(ii) A SPDES permit, if applicable.
(3) All approvals for new subsurface sewage treatment systems are conditioned on the applicant's submission of as-built drawings, prepared by a design professional, once construction is complete.
(4) An application for review and approval of an alteration or modification of a subsurface sewage treatment system, or of the resumption of use of a subsurface sewage treatment following discontinuation, that cannot satisfy the requirements applicable to new subsurface sewage treatment system must include all of the information in paragraph (1) of subdivision (d) of this section, except that the Department may, at its option, waive the requirement to submit a soil investigation report. For an intermediate sized sewage treatment system, the application must include the information in paragraph (2) of subdivision (d) of this section. An application must also contain:
(i) Plans or other design information, consisting of:
(a) If available, design plans for the subsurface sewage treatment plans, indicating all known regulatory approvals for such plans;
(b) If design plans are not available, a description of the components of the system prepared by a licensed professional engineer;
(ii) A proposal for enhancements to the system to meet the standards in 15 RCNY § 18-38 applicable to a new subsurface sewage treatment system to the extent possible, including the information required under 15 RCNY § 18-38(c); and
(iii) Any additional information demonstrating any or all of the following:
(a) A reduction in the potential for contamination to or degradation of the water supply from the subsurface sewage treatment system,
(b) A reduction in flow to the subsurface sewage treatment system, or
(c) Mitigation measures to avoid contamination to, or degradation of, the water supply.
(e) Construction Requirements.
(1) The applicant must notify the Department at least two business days before the start of construction of a subsurface sewage treatment system. The locations of the absorption field corners, septic tanks, pump or dosing chambers, and other treatment components must be staked out before the start of construction, so that the Department can, at its option, verify compliance with separation distance to wells, watercourses, and property lines. The ends of absorption trenches and the corners of absorption beds must be staked out before the start of construction. Stakes must be marked with applicable line and grade information and may not be disturbed during construction.
(2) If construction of a subsurface sewage treatment system ceases for more than seven days, the applicant must make best efforts to notify the Department at least two business days before restarting construction.
(3) The applicant must notify the Department at least one day before burying any component of a subsurface sewage treatment system.
(4) All notifications to the Department pursuant to this subsection (d) must be made via the email address and/or telephone number listed on the approval.
(Amended City Record 10/30/2019, eff. 11/29/2019)
Source: City of New York, Charter, Administrative Code and Rules (American Legal Publishing XML export, codelibrary.amlegal.com)URL: https://codelibrary.amlegal.com/codes/newyorkcity/latest/NYCrules/0-0-0-124142Fetched: 10/24/2026