Source: http://www.dec.ny.gov/regs/4508.html
Timestamp: 2014-10-23 06:42:05
Document Index: 760227025

Matched Legal Cases: ['art 646', 'art 646', 'art 646', '§646', '§646', '§646', 'art 645', '§646', '§646', '§646', '§646', '§646', '§646', '§646', '§646', '§646', '§646', 'art 645', '§646', '§646', '§646', '§646', '§646', 'art 645', 'art 111', 'art 111', '§806', '§807']

Subpart 646-4 Stormwater Management - NYS Dept. of Environmental Conservation
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Subpart 646-4 Stormwater Management
646-4.16 Maintenance of Stormwater Control Facilities under Stormwater Regulatory Programs
§646-4.1 Preamble
Environmental Conservation Law, section 43-0112 directs the Lake George Park Commission ("commission") to develop regulations to guide preparation of local stormwater management plans and regulatory programs. The statutory provisions state that municipalities within the Lake George Park shall develop and implement the plans and programs consistent with the regulations and subject to the approval of the commission not later than 18 months from the effective date of the regulations. If the commission determines that a municipality has failed to develop a plan or program or fails to implement an approved plan or program, then the commission shall assume the authority of the municipality to do so. The regulations are contained in this Subpart and they first became effective on September 19, 1990. The regulations provide that the commission prepare a model ordinance as an aid to local government and a means to streamline review of local regulatory programs. The Model Ordinance was completed and provided to each municipality on December 15, 1990. The commission also prepared and established additional aids for the municipalities. On April 17, 1992, following expiration of the 18-month statutory timeframe, the commission assumed jurisdiction over stormwater in three municipalities which had determined not to develop a plan or regulatory program. Before the commission approved any local regulatory program or stormwater plan in municipalities which had determined to develop a plan or regulatory program, the regulations were amended. This section was added to put these amendments in context. The purpose of the amendments was to reduce procedural and regulatory inconsistencies which had been identified during the review of several preliminary local stormwater regulatory programs and which had a direct bearing on decisions affecting municipal programs which had been submitted for approval. The timing of the amendments was such that the revisions would be in place prior to review and approval of local regulatory programs and stormwater management plans. Thus, no local plan or regulatory program was approved prior to the referenced amendments. Accordingly, the amendments include a provision which affords additional time for municipalities to complete action on local programs and plans. In the interest of ensuring that the water quality protection benefits of improved stormwater management not be unduly delayed, the amendments set a time period of nine months from notice of the effective date of the amendments to this Subpart within which the municipalities must act to complete and implement a stormwater management plan and regulatory program. Once the nine-month period has passed and a municipality is not in compliance with the time limit set forth in this Subpart, the regulations provide that the commission shall assume jurisdiction over stormwater in such a municipality.
§646-4.2 Purpose and Intent
The purpose of this Subpart is to protect and safeguard the general health, safety, and welfare of the public residing in or visiting the park by preserving and protecting the quality of the ground and surface waters of the park. This Subpart has the following objectives: prevent any increase in stormwater runoff from any development in order to reduce flooding, siltation and streambank erosion; prevent any increase in pollution caused by stormwater runoff from development which would otherwise degrade the quality of water in Lake George and its tributaries and render it unfit for human consumption, interfere with water based recreation or adversely affect aquatic life; and ensure that the total annual volume of surface water runoff which flows from any specific site during and following development shall not exceed that which prevailed prior to development.
§646-4.3 Applicability
(c) Applicability under commission jurisdiction. In any municipality where the commission has assumed jurisdiction over stormwater management pursuant to Environmental Conservation Law, section 43-0112(3) and sections 646- 4.5 and 646-4.6 of this Subpart, a permit from the commission shall be required in accordance with sections 646-4.5, 646-4.12 and 646-4.13 of this Subpart. The design standards for stormwater controls contained in this Subpart shall be applicable in the review of permit applications. Permit applications shall be processed in accordance with the provisions of Subpart 645-5 of this Title except that the project classifications contained herein shall govern.
§646-4.4 Definitions
(9) Detention-structure means a permanent structure for the temporary storage of runoff which is designed so as not to create a permanent pool of water.
(12) Development area or site means: any parcel of property or lot or combination of contiguous lots which:
(i) are in common ownership; or
(ii) are in diverse ownership where development is to occur in common. For the purposes of this Subpart, contiguous lands shall include those separated by a public highway.
(27) Offering plan means a prospectus as required by section 352-e of the General Business Law.
(43) Significant habitat means that area or region important in fulfilling the daily or seasonal habitat requirements of any species of plant or animal designated as endangered, threatened, rare, or of special concern by the department pursuant to Environmental Conservation Law, sections 11-0535 and 9-1503 and the department's regulations thereunder, or by any individual species or any group or natural community of nonlisted plants and animals of significant economic, recreational, aesthetic, ecological or scientific importance.
(45) Site. See development area, paragraph (12) of this subdivision.
(51) Stormwater management means:
(i) for quantitative control, a system of vegetative and structural measures that control the increased volume and rate of surface runoff caused by human-made changes to the land; and
(ii) for qualitative control, a system of vegetative, structural and other measures that reduce or eliminate pollutants that might otherwise be carried by surface run-off.
(53) Stormwater management plan or plan means a local stormwater management plan adopted by a municipality pursuant to this Subpart and Environmental Conservation Law, section 43-0112.
(55) Stormwater regulatory program or program means a local stormwater regulatory control program adopted by a municipality pursuant to this Subpart and Environmental Conservation Law, section 43-0112.
(57) Stream shall include any permanent or intermittent watercourse.
(58) Stream corridor means that area within 100 feet of the high-water mark of any stream or river protected and/or regulated by New York State Department of Environmental Conservation, or wetlands adjacent thereto.
§646-4.5 Prohibitions
(a) Wherever the commission has assumed jurisdiction for stormwater management within the Lake George Park pursuant to section 43-0112(3) of the Environmental Conservation Law and unless otherwise exempted herein, no person shall build, construct, erect, expand or enlarge any building or structure or place or construct any impervious surface such as pavement, blacktop, macadam, packed earth and crushed stone without first receiving a permit issued by the commission pursuant to this Subpart.
(c) Except for the activities exempted herein, no person shall operate a land clearing machine such as a backhoe, grader, or plow or similar device so as to clear, grade, or otherwise remove vegetative cover or soil or to overlay natural vegetative cover with soil or other materials when such activity involves an area of land greater than 5,000 square feet without first receiving a permit from the commission pursuant to this Subpart.
(1) emergency repairs to any stormwater control measure;
(2) development involving land disturbance and land clearing of less than 5,000 square feet which does not result in the creation of new impervious surfaces of more than 1,000 square feet;
(3) any logging or agricultural activity which is consistent with a soil conservation plan approved by the appropriate county soil and water conservation district or a timber management plan prepared or approved by the department, as applicable;
(4) any building, construction or land clearing occurring outside the drainage basin of Lake George from which all stormwater discharged from the development site is discharged outside the basin;
(5) activities of an individual engaging in home gardening by growing flowers, vegetables and other plants primarily for use by that person and his or her family; and
§646-4.6 Stormwater Management Plans and Stormwater Regulatory Programs Required
(a) Each municipality shall adopt a stormwater management plan, and a stormwater regulatory program designed to implement said plan. Stormwater management plans and regulatory programs and amendments thereto shall be consistent with the requirements of this Subpart, and subject to the approval of the commission before they are effective. Plans and programs need not be adopted at the same time.
(c) A municipality may base its stormwater regulatory program upon the Model Stormwater Management Ordinance, Appendix A (see section 646-4.18 of this Subpart) and shall modify the ordinance, if necessary, to conform to its plan and its land use planning procedures. Where a municipality has revised the model ordinance so that it conforms to its plan and land use planning procedures, the adoption of such an ordinance by the municipality shall require commission approval in accordance with this Subpart. The adoption of the Model Stormwater Management Ordinance, without revision, by a municipality as a local ordinance or local law shall be deemed to satisfy the requirements of this Subpart and shall be deemed an approved stormwater regulatory program.
(d) The commission may enter into an agreement with any municipality for the shared implementation and enforcement of stormwater regulatory programs. Such agreements may include commission delegation of some or all of the authority assumed pursuant to Environmental Conservation Law, section 43-0112.
(e) If any municipality fails to implement a stormwater regulatory program approved in accordance with this Subpart, the commission shall assume, after providing for notice and an opportunity to be heard, by resolution, the authority to do so pursuant to section 646-4.7(k) of this Subpart. Some sections within this Subpart, referring to stormwater regulatory standards and procedures, do not identify the entity which has decisionmaking, implementation and enforcement authority with regard to such regulatory standards and procedures. These sections are to be read with the knowledge that the entity within such sections is either the commission or a municipality depending on who has the decisionmaking, implementation and enforcement authority pursuant to this Subpart.
(f) No plan or program shall be required for the Towns of Horicon, Lake Luzerne and Warrensburg. All development within those municipalities and within the park and within the lake drainage basin shall be the subject of agreements between the respective municipality and the commission pursuant to subdivision (d) of this section.
§646-4.7 Time Limits for Preparation and Procedures for Review of Stormwater Management Plans and Stormwater Regulatory Programs
(a) The commission shall mail notice to the chief executive officer of each municipality advising of the effective date of this Subpart, amendments thereto, the completion of the stormwater feasibility study prepared pursuant to Environmental Conservation Law, section 43-0112(2), the completion of a local stormwater plan or any other event which affects the content of plans or programs. The notice shall specify that the time frame within which the municipality has to prepare plans and programs or make amendments thereto has commenced.
(b) Each municipality shall be afforded a period of 90 days from the effective date of this Subpart, amendments thereto, the completion of a local stormwater plan or any other event which effects the content of plans or programs to deliver written notice of the municipality's intention to develop a plan and/or program, or make any necessary amendments to existing and approved plans and/or programs. This intention must be adopted by the majority vote of the governing body of the municipality.
(c) The initial time period within which each municipality had to prepare a plan and program, after the effective date of this Subpart, was 18 months in accordance with Environmental Conservation Law, section 43-0112(1)(a). This 18-month time period has expired. The time limit for preparing plans and programs shall be nine months from the date of notice, as required in subdivision (a) of this section, of the 1998 amendments to this Subpart. The time limit for amending existing and approved plans or programs shall be nine months from the date of notice of any amendments to this Subpart, the completion of the study recommendations pursuant to Environmental Conservation Law, section 43-0112(2) and (6), or any other event which affects the content of plans and programs.
(f) Whenever the commission determines that the provisions of a proposed stormwater plan or program or proposed amendments to a previously approved plan or program are inconsistent with Environmental Conservation Law, section 43-0112 or with the requirements of this Subpart, it shall notify the municipality of the inconsistent provisions and request that the appropriate changes be incorporated. Such notice shall be in writing and shall specify a time period for the municipality to decide whether to make amendments to the preliminary plan or program consistent with the commission's recommendations.
(1) whether the plan, program or amendment thereto complies with the requirements of Environmental Conservation Law, section 43-0112 and this Subpart;
(2) whether the plan, program or amendment thereto has been amended to adequately respond to recommendations and comments of the commission; and
(i) Following commission approval, a plan shall be adopted by the board of the municipality within 60 days. Following commission approval a program shall be adopted as a local ordinance or local law by the board of the municipality within 60 days. The 60-day time periods shall begin the day after commission approval of a plan and/or program.
(1) a municipality has determined not to prepare a plan or program;
(2) a municipality has failed to adopt a plan or program; to meet any time limit for the delivery of the notice of intent, the submission or adoption of a plan or program, or the incorporation of amendments to this Subpart and recommendations made pursuant to Environmental Conservation Law, section 43-0112(2) in any existing and approved plan and/or program; or
§646-4.8 General Requirements for Stormwater Management Plans
Each municipality's stormwater management plan shall, at a minimum:
(a) Provide for the implementation of the plan and its integration with other components of the municipality's land use planning program, such as zoning, subdivision, sanitary and site plan review controls, provide for the coordination of stormwater management with adjoining communities, and provide for public participation in stormwater planning and decisionmaking.
§646-4.9 Stormwater Management Plan Requirements in Areas Where Development Is Occurring
Each stormwater management plan shall, at a minimum, include the following elements for those areas where new land use and development, including redevelopment, is occurring or where, under applicable zoning or other land use controls, new land use and development may occur in the future:
(a) Maps of individual parcels and general land areas where development is occurring or may occur in the future delineating the location and capacity of the existing stormwater infrastructure serving those parcels or areas, including community storm-sewers and human-made retention and detention control structures as well as natural stormwater control features. Such maps shall also depict major roads, streams, watersheds, ponds, wetlands, land use zones, soil types and areas with slopes generally greater than 15 percent and delineate, within each watershed, lands having potential for use as dedicated stormwater recharge areas. The commission shall establish standardized map formats and uniform scales to be used by the municipalities to promote the goal of a consistent planning reference for the park.
§646-4.10 Stormwater Management Plan Requirements for Developed Areas
(a) Pursuant to Environmental Conservation Law, section 43-0112(2) the commission shall prepare a study of the feasibility of reducing the impacts of stormwater runoff in areas where development has already occurred. The recommendations of such study shall be incorporated into stormwater management plans and stormwater regulatory programs. Municipalities nevertheless should identify, early in the planning process, geographic areas and land-based activities requiring attention to alleviate adverse stormwater related impacts upon water quality and erosion. Municipalities are also encouraged to begin to consider policies and methods to address such impacts prior to completion of the study.
(2) an analysis of existing data on flows and pollutants discharged from major stormwater outfalls and an evaluation of the need to gather additional data in order to:
(i) establish baseline levels of elements and compounds being discharged at major stormwater out falls; and
(ii) rank major stormwater outfalls in order of the amount, levels and volume of stormwater and pollutant loads being discharged;
(3) specific objectives which can reasonably be expected to be undertaken by State and local government to reduce or prevent any increase in stormwater runoff and stormwater pollution from new development or redevelopment. In setting specific objectives, the plan shall evaluate the following:
(i) construction of new stormwater management facilities such as siltation traps, catch basins, and/or retention ponds, independently, or as part of any public road project or other development;
(ii) improved maintenance of existing stormwater management facilities;
(iii) targets for reduction in volume of road deicing sand and salts;
(iv) improvements in runoff controls at road sand and salt storage areas;
(v) reduction in the volume of fertilizers and pesticides applied to public and private lands;
(vi) action to improve spring cleanup of road sand and salt including identification of suitable disposal sites;
(vii) alteration of existing stormwater facilities to reduce the volume of stormwater mixed with surface water flows from the undeveloped upland thereby reducing the volume of polluted water to be controlled;
(viii) action to stabilize eroding areas such as road banks, stream crossing sites, sand and gravel mines; and
(ix) action to improve street sweeping, litter and lawn clipping and other housekeeping measures; and
§646-4.11 General Requirements for Stormwater Regulatory Programs
Each municipality shall adopt a stormwater regulatory program which shall include permit requirements, standards, compliance mechanisms and enforcement provisions governing the design, construction, operation and maintenance of stormwater management facilities.
(2) contain a statement of purpose and intent compatible with this Subpart and Environmental Conservation Law, section 43-0112(b) and (c);
(16) provide for coordination of review with adjoining municipalities for projects located in more than one municipality and include measures to ensure that the effects of stormwater runoff in all affected municipalities are considered;
(19) include, if deemed desirable or necessary by the municipality for the protection of the water quality and resources of the park, provisions determining whether previously approved subdivisions must obtain stormwater management permits prior to the further sale of additional lots; and
§646-4.12 Project Classification in Stormwater Regulatory Programs for the Purpose of Review
(i) Any part of the activity listed in paragraph (a)(1), (2) or (3) of this section which occurs on:
(a) soils of high potential for overland or through-soil pollutant transport;
(b) an area with a slope of 15 percent or greater when measured in any direction over a distance of 100 feet from the center of the proposed building site; or
(c) an area with a soil percolation rate slower than 60 minutes per inch.
(ii) Any minor project may be treated as a major project if such treatment is desirable due to specific site limitations or constraints, anticipated environmental impacts, or the need or advisability of additional public notice and comment. When determining whether to treat a minor project as a major project, the criteria to be considered shall include, but shall not be limited to, whether the site lies within or substantially contiguous to a:
(a) a critical environmental area established pursuant to SEQR;
(c) a stream corridor;
(d) an area of significant habitat for any wildlife or plant species; or
(e) an area of particular scenic, historic or natural significance. The project sponsor of a minor project that will be treated as a major project shall be given a written statement of the reasons for such a determination.
§646-4.13 Permit Application Procedures in Stormwater Regulatory Programs
Stormwater permit applications shall be processed in accordance with Subpart 645-5 of this Title.
(6) The names and legal mailing addresses of all landowners adjacent to the project site. For major projects, the names and legal mailing addresses of all landowners within 500 feet of the project site.
(7) A detailed plot plan which shows the site topography, the location and dimensions of all existing and proposed structures and impervious surfaces, water bodies, septic systems, wells, and stormwater control devices on the site and within 100 feet of the site.
(2) The SCP and SCR shall be prepared by an engineer or architect or exempt land surveyor licensed to practice under the laws of the State of New York, who shall be employed by the applicant or developer to design and supervise the installation of all stormwater management facilities. Stormwater management shall be within the area of expertise of the particular individual or firm performing the design and construction supervision, and if requested, that individual or firm shall furnish a listing and description of all stormwater management projects designed or supervised by them within the past five years.
(1) A description of the project site and surrounding area within 500 feet as it exists prior to the commencement of the project; a location map; description of the watershed of the subcatchment and its relation to the project site; soil types and descriptions on the site and surrounding area; topography of the project site and surrounding area; surface characteristics including percent cover by asphalt, concrete, crushed stone, grasses, brush, and trees; current land use including all structures, and characteristics of the shoreline and its development, if applicable; drainage patterns including streams, ponds, culverts, ditches, and wetlands; and locations of utilities, roads, and easements.
(3) Hydrologic and hydraulic computations of stormwater volume and flow for existing and proposed conditions shall be performed. Such computations shall include:
(i) description of the design storm frequency, intensity and duration;
(iii) soil curve numbers or runoff coefficients;
(iv) peak runoff rates and total runoff volumes for each watershed area or subcatchment area;
(v) infiltration rates;
(vi) culvert capacities;
(viii) data on the increase in rate and volume of runoff for the 10-year storm and on the change in the rate of runoff for the 2-, 10-, 50- and 100- year storms;
(ix) documentation of sources for all computation methods and field test results; and
(x) sufficient information to demonstrate that the proposed development, with its necessary stormwater controls, has been designed to preserve and maintain the base flow in all streams passing through, adjoining or receiving runoff from the site.
(5) A detailed description of and plans of, stormwater and erosion control measures including:
(i) proposed containment facilities and structures;
(ii) calculations of infiltration area required;
(iii) calculation of retention and/or detention/retention storage requirements and storage volume provided;
(iv) calculation or documentation of infiltration rate;
(v) calculation for release rate controls (orifice or pipe size);
(vi) description of pollution control measures such as filter strips, sand filters, infiltration;
(vii) provision for emergency overflow; and
(viii) measures taken to obviate or reduce the need for runoff control such as use of porous pavement or crushed stone, or the minimization of land clearing or paving.
(7) A certification that the stormwater control measures as designed and presented in the SCR will function adequately, will not adversely affect adjacent or downstream waters or properties, and have been designed in accordance with these regulations and the provisions of Environmental Conservation Law, section 43-0112. The report and plans shall bear the stamp and signature of the licensed professional engineer or architect or exempt land surveyor executing the above certification.
(8) A project schedule which shall indicate the proposed starting and completion dates for all major work phases including, but not limited to, clearing and grading, road construction, utility placement, septic systems, stormwater control measures, wharf construction, pouring or laying of footings and foundations, building construction, and interim and permanent revegetation. Particular emphasis shall be placed on those elements of the schedule relating to stormwater runoff and erosion control. In general, the stormwater control measures shall be installed first in the construction stages of a project to minimize the impacts associated with construction. Further, the project schedule shall take into account appropriate seasonal limitations for temperature and weather sensitive operations. Special measures or procedures may be required to undertake land disturbance activities occurring between October 15th and April 15th.
(9) A maintenance schedule which includes:
(i) the construction costs related to stormwater control;
(ii) the proposed stormwater control maintenance program and annual costs of implementing such;
(iii) identification of the party or parties responsible for maintenance of the system over the life of the project;
(iv) a copy of any maintenance agreement; and
(v) identification of the party or parties responsible for correcting failures or inadequate function of stormwater control measures and responsible for assuming control of the measures in the event of failure to properly maintain the system.
§646-4.14 Design Requirements and Performance Standards for Stormwater Regulation
(1) Stormwater shall be managed on-site using stormwater control measures designed to afford optimum protection of ground and surface waters. Stormwater control measures shall be selected by giving preference to the best management practices for pollutant removal and flow attenuation in accordance with the chart found in subparagraph (b)(4)(i) of this section. Stormwater may be calculated in accordance with the methodology in paragraph (b)(1) and subparagraph (b)(3)(i) of this section or, in the alternative, at a flat rate of 1.5 gallons of stormwater for every square foot of net increase in impervious area. Net increase is the difference between pre-development and post-development conditions. All water from newly created impervious which would otherwise runoff the parcel shall be directed to an infiltration device. Location of the infiltration device shall be determined based upon soil test results.
(3) Infiltration devices shall not be installed up gradient within 20 feet of the subsurface treatment system of a wastewater treatment system. Infiltration devices for roadways, parking lots, and other areas subject to vehicle and traffic shall not be installed within 100 feet of any water well, wetland or water body.
(4) Infiltration devices and buildings shall be located to maintain maximum attainable horizontal distance separation from wells, wetlands and waterbodies. Pumping stormwater shall not be permitted.
(7) Stormwater control measures proposed to be installed at locations with slope > 15 percent before grading, soil percolation rate slower than 60 minutes per inch or which require placement of fill to meet horizontal distance separations specified in this Subpart shall be designed by a licensed professional engineer, architect or exempt land surveyor.
(1) Methodologies for determination of runoff volume. Stormwater volumes and rates of flow shall be calculated using the following methods:
(i) for small watershed areas (up to 20 acres), any widely accepted method including the rational method may be used; and
(ii) for larger watershed areas any widely accepted method other than the rational method may be used.
(2) Design requirements for erosion controls.
(i) Erosion control shall be provided for all disturbed areas in accordance with sections 3, 4, 5, 6 and 7 of the New York Guidelines for Urban Erosion and Sediment Control which is a publication of the Empire State Chapter of the Soil and Water Conservation Society, P.O. Box 1686, Syracuse, NY 13201- 1686 and dated April 1997. This document is available for public inspection and copying at the Office of the Lake George Park Commission, Fort George Road, Lake George, NY and is available through the New York State Department of State, Office of Information Services, 41 State Street, Albany, New York. The temporary erosion control measures shall be maintained continuously until permanent control measures are in service. Infiltration devices shall be protected from siltation during the period of construction and until the site is successfully revegetated by use of silt screens, inlet protection devices, sediment detention ponds or other suitable erosion control measures.
(ii) Staging of construction to facilitate erosion control shall be required. Only those areas where construction is actively occurring shall remain open and unvegetated. All areas that are not within an active construction area shall be mulched and stabilized or shall be mulched and revegetated. An active construction areais defined as one that has seen substantial construction within the past seven calendar days. Mulching or revegetation for erosion control shall be completed within 10 days following the last substantial construction activity.
(i) Stormwater control measures shall be designed so that there will be no increase in runoff volume from a 10-year frequency/24-hour duration storm event following development over the predevelopment volume.
(ii) For storm events exceeding the 10-year design storm, the stormwater control measures shall function to attenuate peak runoff flow rates for a 25-year frequency storm to be equal to or less than predevelopment flow rates. For development greater than five acres, consistent with New York State Guidelines, stormwater control measures shall function to attenuate peak runoff flow rates for a 100-year, storm to be equal to or less than predevelopment flow rates. Attenuation of the 100-year storm is intended to reduce the rate of runoff from development to prevent expansion of the 100- year flood plain so as to alleviate flooding of improved properties and roadways. The minimum requirement for peak flow attenuation can be waived for the 100-year storm event where it can be proven that downstream flooding is not a concern, such as where excess stormwater runoff is discharged to Lake George or to a regional stormwater facility designed to handle additional volume and peak discharge. The cumulative effect of all proposed development projects within the watershed should be considered in making this determination. Rainfall intensity curves for Lake George, NY shall be used in the design of these stormwater control measures. These curves are annexed to this Subpart in section 646-4.18, Appendix B, entitled Rainfall Intensity Curves. Additionally, for development greater than five acres, coverage is required under a State pollutant discharge elimination system (SPDES) general stormwater permit administered by the department.
(iii) Infiltration devices shall be designed such that the bottom of the system will be a minimum of two feet above the seasonal high groundwater level to be realized following development. Where compliance with this requirement would prevent compliance with subparagraph (vi) of this paragraph, compliance with this requirement may be waived. This provision shall not apply to wet ponds and similar stormwater control measures which are designed to be built in the saturated soil zone.
(iv) Infiltration devices for major projects shall be located a minimum of 100 feet from Lake George and any downgradient drinking water supply, lake, river, protected stream, water well, pond, wet land; a separation of more than 100 feet may be required in cases where contamination of the water supply is possible due to highly permeable soils, shallow groundwater and similar situations. The separation distance shall be minimum of 50 feet from upgradient water supplies. Designs shall mitigate the possible adverse effects that groundwater recharge will have on adjacent wells, water supplies, wastewater treatment systems, buildings, roadways, properties and stormwater control measures. Stormwater recharge areas shall be located a minimum of 100 feet from the subsurface treatment system of a wastewater treatment system unless it is demonstrated that a lesser separation will not adversely affect the functioning of such leach fields.
(v) Infiltration devices shall be designed to extend a minimum of 10 percent of the infiltration surface area below the prevailing frost depth of four feet (whichever is greater) in order to provide infiltration during winter months.
(i) Stormwater control measures shall be used in the following order of preference:
(a) infiltration devices;
(b) artificial wetlands and acceptable natural treatment systems;
(c) flow attenuation by use of open vegetated swales and depressions; or
(d) stormwater detention. Stormwater control measures shall be selected by giving preference to the best management practice for pollutant removal as indicated in the chart below:
(ii) All stormwater control facilities shall be designed to completely drain or return to design levels in accordance with the following: infiltration basin 5 days; infiltration trench 15 days; dry well 15 days; porous pavement 2 days; vegetated depression 1 day.
§646-4.15 Vegetative Cutting and Clearing Restrictions in Stormwater Regulatory Programs
(a) No vegetation shall be felled into any lake, pond, river, stream or intermittent stream and if inadvertently felled into one of these water bodies, shall be removed immediately from the waterbody. The removal of dead, or dying, diseased trees or trees presenting a health or safety hazard shall not be exempt from this requirement.
(b) Within 500 feet of the mean high water mark of any lake, pond, river, stream, or wetland, no land area, including areas stockpiled with earthen materials, which has been cleared may be made or left devoid of growing vegetation for more than 24 hours without a protective covering securely placed over the entire area and/or erosion control devices properly installed to prevent sediments from entering the water body. Acceptable protective coverings include natural mulch of a depth of two inches, rock rip-rap, nondegradable materials such as plastic or canvas coverings, and impervious structures.
(c) Any area of land from which the natural vegetative cover has been either partially or wholly cleared or removed by development activities shall be revegetated within 10 days from the substantial completion of such clearing and construction. Acceptable revegetation shall consist of the following:
(1) reseeding with an annual or perennial cover crop accompanied by placement of straw mulch or its equivalent of sufficient coverage, but not less than 50 percent of the total disturbed area, to control erosion until such time as the cover crop is established over 90 percent of the seeded area;
(2) replanting with native woody and herbaceous vegetation accompanied by placement of straw mulch or its equivalent of sufficient coverage to control erosion until the plantings are established and are capable of controlling erosion; and
(d) Any area of revegetation must exhibit survival of a minimum of 75 percent of the cover crop throughout the year immediately following revegetation. Revegetation must be repeated in successive years until the minimum 75 percent survival for one year is achieved.
(e) Ground clearing or grading activities which occur during the period October 15th to April 15th, during which germination of vegetation typically will not take place, shall be required to incorporate extra measures during revegetation in order to reduce erosion and maintain water quality. These extra measures include, but are not limited to, the use of screen mesh, netting, extra mulch, and siltation fences.
§646-4.16 Maintenance of Stormwater Control Facilities under Stormwater Regulatory Programs
(1) be in writing and be executed by each owner of the project and the municipality, and shall bind the owner(s), their successors and assigns to future maintenance of stormwater control facilities serving the project;
(2) be binding on all owners of lands within the project and all parties to the agreement, their successors and assigns for the life of the project;
(3) include provisions to raise, maintain and expend funds for necessary maintenance and repair functions over the life of the project;
(4) provide that if maintenance and repair activities are not performed in compliance with its terms, the municipality shall be entitled to perform or contract for the necessary services and charge the then current project owners for the cost thereof, including any related legal fees and disbursements; and
§646-4.17 Criteria for Issuance of Permits in Stormwater Regulatory Programs
(a) An application may be approved, denied, or approved with modifications or conditions, including modifications to nonstormwater aspects of the development necessary to achieve the required level of stormwater management.
(b) No stormwater management permit shall be issued unless the following findings are made and are supported by substantial evidence. The facts supporting such findings shall be set forth in the decision document or permit. The issued permits shall set forth all required conditions and incorporate all necessary documents and maps.
(1) That the project meets the design requirements and performance standards set forth in Environmental Conservation Law, section 43-0112, this Subpart and the municipality's stormwater regulatory program, if applicable.
§646-4.18 Variances from Stormwater Regulatory Programs
(b) If the applicant determines that any aspect of the project cannot meet any design or dimensional requirement contained in Subpart, the applicant may make direct application for a variance.
(d) A permit application involving a variance shall be processed in accordance with Subpart 645-5 of this Title except that no variance shall be granted unless the commission finds that the applicant has demonstrated entitlement to the variance pursuant to the criteria in section 267-b3. (b) of the New York State Town Law. The decision on a variance under municipal jurisdiction shall be in accordance with sections 267-a and 267-b of the New York Town Law in the case of a town or sections 7-712-a and 7-712-b of the New York State Village Law in the case of a village, and any amendments thereto provided, however, that the grant of any variance to the shoreline or cutting restrictions of section 806 of the Adirondack Park Agency Act (Executive Law, article 27) must be in compliance with that section and section 807 of the act, if applicable.
(f) In granting any variance, the commission may impose specific conditions upon the proposed use or activity necessary to assure that the use or activity will have no adverse impacts upon the public health, safety or welfare, the environment or the resources of the park. Such conditions may be imposed without regard to whether the commission could otherwise impose such conditions pursuant to the substantive authority of the commission under the Environmental Conservation Law, articles 43 and 71, title 33, or the rules or regulations promulgated by the commission thereunder.
(g) No variance shall be granted by a municipality until first providing notice to the commission a minimum of 15 days in advance. The commission shall be deemed a party to the proceeding for all purposes with the right to initiate or intervene in any action or proceeding in which the grant or denial of a variance is an issue or in any proceeding involving an interpretation of the municipality's plan or program.
(h) Appendix A. Model Stormwater Management Ordinance.
SECTION 1 - SHORT TITLE. This shall be known as the Model Stormwater Management Ordinance.
SECTION 3 - EFFECTIVE DATE. The effective date of this Ordinance shall be_____ .
>(a) Any part of the activity listed in Section 9. A. (1 ),(2) or (3) which occurs on (i) soils of high potential for overland or through-soil pollutant transport; (ii) an area with a slope of fifteen percent (15%) or greater when measured in any direction over a distance of one hundred (100) feet from the center of the proposed building site; (iii) or an area with a soil percolation rate slower than sixty (60) minutes per inch.
>(b) Any minor project may be treated as a major project if such treatment is desirable due to specific site limitations or constraints, anticipated environmental impacts, or the need or advisability of additional public notice and comment. When determining whether to treat a minor project as a major project, the criteria to be considered shall include, but shall not be limited to, whether the site lies within or substantially contiguous to any of the following: (i) a Critical Environmental Area established pursuant to SEQR; (ii) a wetland; (iii) a stream corridor; (iv) an area of significant habitat for any wildlife or plant species; (v) or an area of particular scenic, historic or natural significance.
(1) Stormwater shall be managed on-site using stormwater control measures designed to afford optimum protection of ground and surface waters. Stormwater control measures shall be selected by giving preference to the best management practices for pollutant removal and flow attenuation as specified in Schedule C. Stormwater may be calculated in accordance with the methodology for determining Stormwater volume and flow rates for major projects found in Schedule B. Part 111 or, in the alternative, at a flat rate of 1.5 gallons of stormwater for every square foot net increase in impervious area. Net increase is the difference between predevelopment and post-development conditions. All water from newly created impervious areas which would otherwise run off the parcel shall be directed to an infiltration device. Location of the infiltration devices shall be determined based upon soil test results.
(7) Stormwater control measures proposed to be installed at locations with slope > 15% before grading, soil percolation rate slower than 60 minutes per inch or which require placement of fill to meet horizontal distance separations specified in this subpart shall be designed by a licensed professional engineer, architect or exempt land surveyor.
(1) Stormwater volumes and rates of flow shall be calculated using the methods specified in Schedule B Part 111.
(b) For storm events exceeding the 10-year design storm, the stormwater control measures shall function to attenuate peak runoff flow rates for a 25- year frequency storm to be equal to or less than predevelopment flow rates. For development greater than five (5) acres, consistent with New York State Guidelines, stormwater control measures shall function to attenuate peak runoff flow rates for a 100-year storm to be equal to or less than predevelopment flow rates. Attenuation of the 100-year storm is intended to reduce the rate of runoff from development to prevent expansion of the 100- year flood plain so as to alleviate flooding of improved properties and roadways. The minimum requirement for peak flow attenuation can be waived for the 100-year storm event where it can be proven that downstream flooding is not a concern, such as where excess stormwater runoff is discharged to Lake George or to a regional stormwater facility designed to handle additional volume and peak discharge. The cumulative effect of all proposed development projects within the watershed should be considered in making this determination. Rainfall intensity curves for Lake George, New York shall be used in the design of the stormwater control measures. These curves are annexed to this Ordinance as Schedule D entitled Rainfall Intensity Curves. Additionally, for development greater than five (5) acres, coverage is required under a State Pollutant Discharge Elimination System (SPDES) General Stormwater Permit administered by the Department of Environmental Conservation.
(3) Additional Requirements for Major Projects. (a) Stormwater control measures shall be used in the following order of preference: (i) infiltration devices; (ii) artificial wetlands and acceptable natural treatment systems; (iii) flow attenuation by use of open vegetated swales and depressions; (iv) Stormwater detention. Stormwater control measures shall be selected by giving preference to the best management practice for pollutant removal and flow attenuation as indicated in Schedule C.
(b) All stormwater control measures shall be designed to completely drain to return to design levels in accordance with the following: infiltration basin 5 days; infiltration trench 15 days; dry well 15 days; porous pavement 2 days; vegetation depression 1 day.
(1) Preparation of a Stormwater Control Report in accordance with Schedule B, Part II is required. Preparation of a Stormwater Concept Plan in accordance with Schedule B, Part I may be required if deemed necessary by the municipality. The SCP and SCR shall be prepared by an engineer or architect or exempt land surveyor licensed to practice under the laws of the State of New York, who shall be employed by the applicant or developer to design and supervise the installation of all stormwater management facilities. Stormwater management shall be within the area of expertise of the particular individual or firm performing the design and construction supervision, and if requested, that individual or firm shall furnish a listing and description of all stormwater management projects designed or supervised by them within the past five (5) years.
D. The granting of any variance shall be done in accordance with Sections 267-a and 267-b of the New York State Town Law or Sections 7-712-a and 7-712-b of the New York State Village Law and any amendments thereto as appropriate provided, however, that the grant of any variance to the shoreline or cutting restrictions of §806 of the Adirondack Park Agency Act (Executive Law, Article 27) must be in compliance with that Section and §807 of the Act, if applicable.
(21) Infiltration device means a stormwater recharge area, drywall, recharge basin, retention basin or any other engineered structure designed to infiltrate stormwater.
(25) Municipality means the Town of (Village of).
(48) Stormwater control measures means all those natural and manmade structures, infiltration devices, erosion controls, systems, facilities, agreements, institutional arrangements, and financial provisions to manage stormwater including, but not limited to, any of the following: dry wells, pits of crushed rock, infiltration trenches, retention ponds, detention ponds, blind ditches, swales, pipes, culverts, natural depressions, porous paving, recharge areas, and basins.
(53) Stormwater Management Plan or Plan means a local stormwater management plan adopted by a municipality pursuant to this Subpart and ECL Section 43- 0112.
(55) Stormwater Regulatory Program or Program means a local stormwater regulatory control program adopted by a municipality pursuant to 6 NYCRR 646-4 and ECL Section 43-0112.
(3) Hydrologic and hydraulic computations of stormwater volume and flow for existing and proposed conditions shall be performed. Such computations shall include (i) description of the design storm frequency, intensity and duration, (ii) time of concentration, (iii) soil curve numbers or runoff coefficients, (iv) peak runoff rates and total runoff volumes for each watershed area or subcatchment area, (v) infiltration rates, (vi) culvert capacities, (vii) flow velocities, (viii) data on the increase and volume of runoff for the 10-year storm and on the change in the rate of runoff for the 2-, 10-, 50- and 100-year storms, (ix) documentation of sources for all computation methods and field test results, and (x) sufficient information to demonstrate that the proposed development, with its necessary stormwater controls, has been designed to preserve and maintain the base flow in all streams passing through, adjoining or receiving runoff from the site.
Methodologies for determining runoff volume. Stormwater volumes and rates of flow shall be calculated using the following methods: (i) for small watershed areas (up to 20 acres), the Rational Method may be used, and (ii) for larger watershed areas (up to 2,000 acres), and as the overall preferred method, the United States Department of Agriculture method shall be used, (this method is described in "Urban Hydrology for Small Watersheds-Technical Release 55") or (iii) any other equivalent and widely accepted method may be used.
COMPARATIVE POLLUTANT REMOVAL OF
URBAN BMP DESIGNS
APRIL 1992. FIGURE 15
Whereas, the Municipality of_____ ("Municipality") and the _____ ("facility owner") want to enter into an agreement to provide for the long term maintenance and continuation of stormwater control measures approved by the Municipality for the below named project, and
8. This agreement shall be recorded in the Office of the County Clerk, County of_____ together with the deed for the common property and shall be included in the offering plan and/or prospectus approved pursuant to _____.
10. This agreement is effective_____
(i) Appendix B. Rainfall intensity curves for Lake George, NY.