Montgomery Town City Zoning Code
§ 235-10.6
Stormwater pollution prevention plans SWPPP.
A.
Stormwater pollution prevention plan requirement. No application for approval of a land development activity and/or building permit shall be approved until the appropriate board or the Building Department has received a stormwater pollution prevention plan (SWPPP) prepared in accordance with the specifications in this § 235-10.
B.
Contents of all stormwater pollution prevention plans. All SWPPPs shall provide the following background information and erosion and sediment controls:
(1)
Background information about the scope of the project, including location, type and size of project.
(2)
Site map/construction drawing(s) for the project, including a general location map. At a minimum, the site map should show the total site area; all improvements; areas of disturbance; areas that will not be disturbed; existing vegetation; on-site and adjacent off-site surface water(s); wetlands and drainage patterns that could be affected by the construction activity; existing and final slopes; locations of off-site material, waste, borrow or equipment storage areas; and location(s) of the stormwater discharges(s). The site map should be at a scale no smaller than one inch equals 100 feet.
(3)
Description of the soil(s) present at the site.
(4)
Construction phasing plan describing the intended sequence of construction activities, including clearing and grubbing, excavation and grading, utility and infrastructure installation and any other activity at the site that results in soil disturbance. Consistent with the New York Standards and Specifications for Erosion and Sediment Control (Erosion Control Manual), not more than five acres shall be disturbed at any one time unless pursuant to an approved SWPPP.
(5)
Description of the pollution prevention measures that will be used to control litter, construction chemicals and construction debris from becoming a pollutant source in stormwater runoff.
(6)
Description of construction and waste materials expected to be stored on site with updates as appropriate, and a description of controls to reduce pollutants from these materials, including storage practices to minimize exposure of the materials to stormwater, and spill prevention and response.
(7)
Temporary and permanent structural and vegetative measures to be used for soil stabilization, runoff control and sediment control for each stage of the project from initial land clearing and grubbing to project close-out.
(8)
A site map/construction drawing(s) specifying the location(s), size(s) and length(s) of each erosion and sediment control practice.
(9)
Dimensions, material specifications and installation details for all erosion and sediment control practices, including the siting and sizing of any temporary sediment basins.
(10)
Temporary practices that will be converted to permanent control measures.
(11)
Implementation schedule for staging temporary erosion and sediment control practices, including the timing of initial placement and duration that each practice should remain in place.
(12)
Maintenance schedule to ensure continuous and effective operation of the erosion and sediment control practice.
(13)
Name(s) of the receiving water(s).
(14)
Delineation of SWPPP implementation responsibilities for each part of the site.
(15)
Description of structural practices designed to divert flows from exposed soils, store flows, or otherwise limit runoff and the discharge of pollutants from exposed areas of the site to the degree attainable.
(16)
Any existing data that describes the stormwater runoff at the site.
C.
Classification. Land development activities shall be classified by the SMO as any one or more of the following conditions:
(1)
Condition A: stormwater runoff from land development activities discharging a pollutant of concern to either an impaired water identified on the Department's 303(d) list of impaired waters or a total maximum daily load (TMDL) designated watershed for which pollutants in stormwater have been identified as a source of the impairment.
(2)
Condition B: stormwater runoff from land development activities disturbing five or more acres.
(3)
Condition C: stormwater runoff from land development activities disturbing between one acre and five acres of land during the course of the project, exclusive of the construction of single-family residences and construction activities at agricultural properties.
(4)
Condition D: stormwater runoff from land development activities disturbing less than one acre.
D.
Additional SWPPP requirements for Conditions A, B and C:
(2)
Description of each post-construction stormwater management practice.
(3)
Site map/construction drawing(s) showing the specific location(s) and size(s) of each post-construction stormwater management practice.
(4)
Hydrologic and hydraulic analysis for all structural components of the stormwater management system for the applicable design storms.
(5)
Comparison of post-development stormwater runoff conditions with predevelopment conditions.
(6)
Dimensions, material specifications and installation details for each post-construction stormwater management practice.
(7)
Maintenance schedule to ensure continuous and effective operation of each post-construction stormwater management practice.
(8)
Maintenance easements to ensure access to all stormwater management practices at the site for the purpose of inspection and repair. Easements shall be recorded on the plan and shall remain in effect with transfer of title to the property.
E.
The Town's "Standard Plan," otherwise known as the "Town SWPPP," for Condition D is as follows: This Standard Plan is issued by the Town of Montgomery and is subject to any special conditions listed on the application. New York State law requires that provisions to control erosion and sediment shall be included for all construction where any excavation, stripping, filling, grading or earth movement takes place. As required by state law, building permits cannot be issued until such erosion and sediment control provisions are approved. Owners and applicants are advised that building permits are not issued until this plan is implemented and site approval has been granted.
(1)
Applicability. This Standard Plan may only be utilized for minor grading activities associated with minor commercial and residential construction for earth disturbances where all the following conditions are met:
(a)
The lot is on a paved, graveled, or publicly maintained street where storm drain facilities are in operation and roadside ditches stabilized.
(b)
Stormwater management facilities are not required on the lot. (For projects where facilities have been designed, this plan represents a starting point, but is not sufficiently comprehensive.)
(c)
No more than 15,000 square feet will be disturbed during development of any one lot, but in any critical area, not more than 5,000 square feet will be disturbed.
(d)
Steep slopes with a grade of 15% or greater will not be disturbed. A twenty-five-foot undisturbed buffer must be maintained from the top of 25% or greater slopes within a sensitive area.
(e)
Development for minor subdivision will take place on not more than two lots at one time.
(f)
Any proposed grading will not impair existing surface drainage, constitute a potential erosion hazard, or act as a source of sedimentation to any adjacent land or watercourse, or affect any sediment and erosion control plan previously approved by the Town of Montgomery.
(g)
Changes in grade or removal of vegetation shall not take place in established buffers or within 100 feet of the mean high water line of a body of water, except for approved buffer management plans disturbing less than 5,000 square feet and the establishment of approved shoreline erosion control projects where no grading is to take place.
(h)
The proposed construction is not subject to a separate erosion and sediment control plan.
(2)
Conditions.
(a)
Access to the site and this plan shall be available at all times for inspection by representatives of the Town of Montgomery.
(b)
The applicant/permittee shall notify the Town of Montgomery at least 48 hours prior to commencing clearing or grading (telephone number: 845-457-2660).
(c)
This Standard Plan is valid only if development of the lot proceeds in accordance with state laws and the rules and regulations governing sediment control, land use, and environmental impact.
(d)
In the event that the applicant fails to provide adequate sediment controls according to the provisions of this plan and standards and specifications, or if the sediment controls installed on the site do not provide adequate protection, the Town of Montgomery Code Enforcement Officer and the Town Engineer may stop all work at the referenced site and require corrective actions.
(e)
This Standard Plan is subject to revocation by the Town of Montgomery or the Code Enforcement Officer whenever determination is made, and after notice is given, that the site is in violation of the rules and regulations promulgated under state law and/or the conditions specified by this plan.
(f)
If there is any concurrent construction on adjoining lots, the Town of Montgomery may take individual and separate actions to assure sediment controls are in compliance with state laws and the approved erosion and sediment control plan.
(g)
Nothing herein relieves the applicant/permittee from complying with any and all of the state laws and regulations.
(h)
This Standard Plan is valid for the life of the building permit or a period of six months if not associated with a building permit.
(3)
Grading.
(a)
Initial clearing and earth disturbance shall be limited to that necessary to install sediment control measures. Excavation for footings, clearing, or other earth disturbance may only take place after the sediment and erosion controls are installed.
(b)
The permanent driveway or entrance location shall be used as a stabilized construction entrance. Two-inch stone shall be placed at a minimum six-inch depth, 30 feet long, and 10 feet wide. The entrance shall be top dressed with stone as necessary to prevent tracking of sediment onto public streets or rights-of-way. Sediment tracked onto public streets must be removed or cleaned on a daily basis. All vehicular traffic onto the site will use this stabilized construction entrance.
(c)
At any location where surface runoff from disturbed or graded areas may flow off the construction area, sediment control measures must be installed, including a silt fence or straw bales to prevent sediment from being transported off site. No grading, filling or other disturbance is allowed within existing drainage swales.
(d)
Swales or other areas that transport concentrated flow shall be sodded. Downspout or sump pump discharges must have acceptable outfalls that are protected by splashblocks, sod, or piping as required by site conditions (i.e., no concentrated flow directed over fill slopes).
(e)
Surface flows over existing or proposed cut and fill slopes shall be controlled by either redirecting flows from traversing the slopes or by installing mechanical devices to safely lower water downslope without causing erosion. Any percolating water resulting from any development activities must be properly conveyed to an acceptable outfall.
(f)
Final graded slopes shall be no steeper than four horizontal units to one vertical unit 25%, nor higher than five feet without prior approval.
(g)
All materials originating from development of the lot and public right-of-way shall be removed immediately to an acceptable disposal facility.
(h)
Final site drainage shall be such to prevent erosion, concentrated flows to adjacent properties, uncontrolled overflow, and ponding. Positive drainage away from the foundation must be provided in accordance with the New York State Code. The foundation must extend at least eight inches above finished grade and a minimum slope of at least 0.5 inch per foot of fall must be maintained away from the foundation.
(4)
Stabilization. Following initial soil disturbance and redisturbance, permanent or temporary stabilization shall be completed within:
(a)
Seven calendar days from the time that the soil is initially disturbed, and before any significant storm event which may have the potential to cause erosion, but not to exceed seven days from initial disturbance.
(b)
Fourteen calendar days for all approved stockpiles and other disturbed or graded areas, provided construction grading activity is not continually ongoing in these locations.
F.
Specifications. Specifications regarding silt fence, straw bale dikes, earth dikes, stone outlet structures, stone construction entrances, temporary and permanent stabilization practices, and any other sediment and erosion control practices are contained in the current New York State Guidelines for Urban Erosion and Sediment Control, as amended and revised. Specifically, the following limitations for silt-fencing may not be exceeded:
(1)
Maximum allowable slope length of the contributing runoff and maximum silt fence length.
Slope Length | Slope Length (feet) | Silt Fence (feet) |
|---|---|---|
2:1 and steeper | 20 | 125 |
3:1 to 2:1 | 40 | 250 |
5:1 to 3:1 | 60 | 500 |
10:1 to 5:1 | 100 | 750 |
50:1 to 10:1 | 125 | 1,000 |
Flatter than 50:1 | 300 | Unlimited |
(2)
Maximum drainage area may not exceed 1/2 acre per 100 feet of silt fence.
(3)
Silt fence must be placed on or parallel to contours where there is no concentration of water flowing to the silt fence and erosion will occur in the form of sheet erosion. The area below the silt fence must be undisturbed ground.
(4)
Silt fence material and installation complies with the standard drawing.
G.
Plan implementation.
H.
Details and specifications for vegetative establishment for Standard Plan.
(1)
Permanent seeding.
(a)
Seedbed preparation. The area to be seeded shall be loose and friable to a depth of at least three inches. The top layer shall be loosened by raking, disking or other acceptable means before seeding occurs. For sites less than five acres, apply 100 pounds of dolomitic limestone and 21 pounds of 10-20-20 fertilizer per 1,000 square feet. Harrow or disk lime and fertilizer into the soil to a depth of at least three inches on slopes flatter than 3:1.
(b)
Seeding. Apply five to six pounds per 1,000 square feet of seed mix between February 1 and May 15 or between August 15 and October 31. Apply seed uniformly on a moist, firm seedbed with a cyclone seeded drill, cultipacker seeder or hydroseeder (slurry includes seeds and fertilizer, recommended on steep slopes only). Maximum seed depth should be 1/4 inch in clayey soils and 1/2 inch in sandy soils when using other than the hydroseeder method. Irrigate if soil moisture is deficient to support adequate growth until vegetation is firmly established. Select seed mixtures from Section 3, New York State Guidelines for Urban Erosion and Sediment Control.
(c)
Mulching. Mulch shall be applied to all seeded areas immediately after seeding. During the time periods when seeding is not permitted, mulch shall be applied immediately after grading. Mulch shall be unrotted, unchopped, small grain straw applied at a rate of two tons per acre or 90 pounds per 1,000 square feet (two bales). If a mulch anchoring tool is used, apply 2.5 tons per acre. Mulch materials shall be relatively free of all kinds of weeds and shall be completely free of prohibited noxious weeds. Spread mulch uniformly, mechanically, or by hand to a depth of one inch to two inches.
(d)
Securing straw mulch. Straw mulch shall be secured immediately following mulch applications to minimize movement by wind or water. The following methods are permitted:
[1]
Use a mulch anchoring tool which is designed to punch and anchor fabric-type mulch into the soil surface to a minimum depth of two inches. This is the most effective method for securing mulch; however, it is limited to relatively flat areas where equipment can operate safely.
[2]
Wood cellulose fiber may be used for anchoring straw. Apply the fiber binder at a net dry weight of 750 pounds per acre. If mixed with water, use 50 pounds of wood cellulose fiber per 100 gallons of water.
[3]
Liquid binders may be used and applied heavier at the edges where wind catches mulch, such as in valleys and on crests of slopes. The remainder of the area should appear uniform after binder application.
[4]
Lightweight netting may be used to secure mulch. The netting will be stapled to the ground according to the manufacturer's recommendations.
(3)
Fill. No fills may be placed on frozen ground. All fill is to be placed in approximately horizontal layers, each layer having a loose thickness of not more than eight inches. All fill in roadways and parking areas is to be classified Type 2 compacted to 90% density; compaction to be determined by ASTM D-1557-66T (Modified Proctor). Any fill within the building area is to be compacted to a minimum of 95% as determined by methods previously mentioned. Fills for pond embankments shall be compacted as per the project engineer's specifications. All other fills shall be compacted sufficiently so as to be stable and prevent erosion and slippage.
(4)
Permanent sod. Installation of sod should follow permanent seeding dates. Permanent sod is to be state-approved sod; lime and fertilizer per permanent seeding specifications and lightly irrigate soil prior to laying sod. Sod is to be laid on the contour with all ends tightly abutting. Joints are to be staggered between rows. Water and roll or tamp sod to ensure positive root contact with the soil. All slopes steeper than 3:1, as shown, are to be permanently sodded or protected with approved erosion control netting. Additional watering for establishment may be required. Sod is not to be applied on frozen ground. Sod shall not be harvested or transplanted when moisture content (dry or wet) and/or extreme temperature may adversely affect its survival. In the absence of adequate rainfall, irrigation should be performed to ensure established sod.
NOTE: This plan does not preclude the applicant from meeting all of the requirements for the New York State Guidelines for Urban Erosion and Sediment Control.
I.
Construction design drawings/specifications.
(1)
Stabilized construction entrances.
(a)
Details.
Stabilized Construction Entrance Details  |
(b)
Construction specifications.
[1]
Stone size. Use two-inch stone or reclaimed or recycled concrete equivalent.
[2]
Length. Not less than 50 feet (except on a single residence lot where a thirty-foot minimum length would apply).
[3]
Thickness. Not less than six inches.
[4]
Width. Twelve-foot minimum, but not less than the full width at points where ingress or egress occurs; 24 feet if single entrance to site.
[5]
Filter cloth. Will be placed over the entire area prior to placing of stone.
[6]
Surface water. All surface water flowing or diverted toward construction entrances shall be piped across the entrance. If piping is impractical, a mountable berm with 5:1 slopes will be permitted.
[7]
Maintenance. The entrance shall be maintained in a condition which will prevent tracking or flowing of sediment onto public rights-of-way. All sediment spilled, dropped, washed or tracked onto public rights-of-way must be removed immediately.
[8]
When washing is required, it shall be done on an area stabilized with stone and which drains into an approved sediment-trapping device.
[9]
Periodic inspection and needed maintenance shall be provided after each rain.
(2)
Silt fences.
(a)
Details.
Silt Fence Details  |
(b)
Construction notes for fabricated silt fence.
[1]
Woven wire fence to be fastened securely to fence posts with wire ties or staples.
[2]
Filter cloth to be fastened securely to woven wire fence with ties spaced every 24 inches at top and mid-section.
[3]
When two sections of filter cloth adjoin each other they shall be overlapped by six inches and folded.
[4]
Maintenance shall be performed as needed and material removed when "bulges" develop in silt fence.
[5]
Posts: steel, either "T" or "U" type, or two-inch hardwood.
[6]
Fence: woven wire, 14.5 ga., six inches maximum mesh opening.
[7]
Filter cloth: Filter X, MIRAFI 100x, Stabilinka T140N or approved equal.
[8]
Prefabricated unit: GeoFab, Envirofence or approved equal.
(3)
Straw bale dikes.
(a)
Details.
Straw Bale Dike Details  |
(b)
Construction specifications.
[1]
Bales shall be placed at the toe of a slope or on the contour and in a row with ends tightly abutting the adjacent bales.
[2]
Each bale shall be embedded in the soil a minimum of four inches and placed so the bindings are horizontal.
[3]
Bales shall be securely anchored in place by either two stakes or rebars driven through the bale. The first stake in each bale shall be driven toward the previously laid bale at an angle to force the bales together. Stakes shall be driven flush with the bale.
[4]
Inspection shall be frequent and repair or replacement shall be made promptly as needed.
[5]
Bales shall be removed when they have served their usefulness so as not to block or impede storm flow or drainage.
(4)
Check dams.
(a)
Details.
Check Dam Details  |
(b)
Construction details.
[1]
Stone will be placed on a filter fabric foundation to the lines, grades and locations shown on the plan.
[2]
Set spacing of check dams to assume that the elevation of the crest of the downstream dam is at the same elevation of the toe of the upstream dam.
[3]
Extend the stone a minimum of 1.5 feet beyond the ditch banks to prevent cutting around the dam.
[4]
Protect the channel downstream of the lowest check dam from scour and erosion with stone or liner as appropriate.
[5]
Ensure that channel appurtenances such as culvert entrances below check dams are not subject to damage or blockage from displaced stones.
(5)
Typical lot erosion and sediment controls.
Typical Lot Erosion and Sediment Control Detail  |
J.
Certifications and permits.
(1)
Plan certification. The SWPPP shall be prepared by a certified professional in erosion sediment control (CPESC) or a certified professional in stormwater quality (CPSWQ) or a professional engineer and must be signed by the professional preparing the plan, who shall certify that the design of all stormwater management practices meets the requirements in this § 235-10.
(2)
Other environmental permits. The applicant shall assure that all other applicable environmental permits have been or will be acquired for the land development activity prior to approval of the final stormwater design plan.
(3)
Contractor certification.
(a)
Each contractor and subcontractor identified in the SWPPP who will be involved in soil disturbance and/or stormwater management practice installation shall sign and date a copy of the following certification statement before undertaking any land development activity: "I certify under penalty of law that I understand and agree to comply with the terms and conditions of the Stormwater Pollution Prevention Plan. I also understand that it is unlawful for any person to cause or contribute to a violation of water quality standards."
(b)
The certification must include the name and title of the person providing the signature; address and telephone number of the contracting firm; the address (or other identifying description) of the site; and the date the certification is made.
(c)
The certification statement(s) shall become part of the SWPPP for the land development activity.
(d)
As of June 1, 2008, all contractors must be certified by the Town of Montgomery or, alternatively, must be under the direct supervision of the certified professional who designed and certified the SWPPP.
(4)
A copy of the SWPPP shall be retained at the site of the land development activity during construction from the date of initiation of construction activities to the date of final stabilization.