§ 300-30. Construction on hillsides and steep slopes.

A. 

Findings. The Common Council has made the following findings concerning the need to address sediment and erosion control during construction on hillsides and steep slopes.

(1) 

Land development can alter hydrologic response. Land development projects and other land use conversions and their associated changes to land cover can alter the hydrologic response of local watersheds and increase stormwater runoff rates and volumes, which in turn can increase flooding, stream channel erosion, and sediment transport and deposition, and can decrease groundwater recharge by creating impervious surface such as pavement and buildings, and compacting pervious surfaces.

(2) 

Cumulative effects. The cumulative effects of several storms on a particular project and the erosion and sediment contributions from several projects can create a significant cumulative effect on water quality, hydrologic response of local watersheds, and can alter or destroy wildlife habitat.

(3) 

Land development can contribute to increased nonpoint source pollution. Land development projects and other land use conversions can contribute to increased nonpoint source pollution and degradation of receiving waters due to the addition of petroleum products, fertilizers and pesticides, construction waste, and other substances to runoff from construction sites.

(4) 

Land development can cause significant environmental damage to wildlife and wildlife habitat. Land development projects can cause significant damage to trees and other wildlife habitat through compaction of soils due to construction vehicle traffic, stripping of vegetation during grading and other site preparation activities, and can increase turbidity in water supplies that may damage the habitat of aquatic species.

(5) 

Stormwater runoff related to development can adversely affect health, safety, welfare, and the environment. The impacts of stormwater runoff related to development can adversely affect public safety, public and private property, surface water supplies, groundwater resources, drinking water, aquatic and nonaquatic wildlife habitats, fish and other aquatic life, property values, and the potential for other uses of land and water.

(6) 

Best management practices can minimize adverse impacts. These adverse impacts outlined above can be controlled and minimized through the application of best management practices during construction activities, low-impact development practices post-construction, and periodic inspections before, during and after construction to ensure that erosion and sediment control practices are functioning effectively.

(7) 

It is therefore in the public interest of health, safety, welfare, and environmental protection to minimize the impacts associated with land development and to regulate stormwater runoff during construction in areas of steep slopes in order to address the adverse impacts to public health, safety, welfare, and the environment detailed in the above subsection.

B. 

Purpose and intent. Based on the findings above, the purpose of this section is to provide for the regulation of development of steep slopes, greater than 15%, by developing standards for design, installation, and maintenance of stormwater management measures during construction on steep slopes for the following reasons:

(1) 

To control the quantity and quality of runoff.

(2) 

To prevent soil erosion and sedimentation resulting from site construction and development.

(3) 

To prevent the pollution of runoff from construction sites.

(4) 

To protect natural resources.

(5) 

To protect other properties from damage that could be caused by erosion and sedimentation or the quantity or quality of runoff.

(6) 

To reduce public expenditures in maintenance of stormwater drainage systems such as removing sediment from systems, repairing or replacing failed systems, restoring degraded natural resources, and to prevent damage to City infrastructure caused by inadequate controls.

C. 

Site plan review. Any and all uses involving the disturbance of more than 1,000 square feet of land surface with slopes greater than 15% shall be subject to site plan review. The Planning Commission has the authority to waive these standards if it determines the area consisting of slopes greater than 15% is small enough so as to pose limited or no environmental risk. The scope of site plan review required under this section shall be limited to the purpose and intent of § 300-30B.

D. 

Strategies and standards.

(1) 

Strategies to be employed. To ensure that all sources of soil erosion and sediment on the construction site are adequately controlled, the following strategies shall be employed:

(a) 

Minimize the areas of disturbed soil. Limit site preparation activities such as grading and clearing to where they are absolutely necessary and consistent with the phasing plan and the daily schedule of construction activities.

(b) 

Maximize the protection and on-site use of native vegetation. Protect all vegetation not intended for removal by adequately marking, fencing around the drip line of trees, protectively wrapping and temporarily transplanting as necessary.

(c) 

Reduce the time that soil is left disturbed. Utilize construction management by phasing; soil disturbed by construction activities shall be stabilized within 14 days of ceasing disturbance.

(d) 

Stabilize soil with seeding and mulch as soon as possible after disturbance.

(e) 

Control water at upslope site perimeters. Prevent stormwater from entering areas of disturbed soil from outside the site and from other parts of the site. Utilize diversion swales and vegetated strips to reduce the amount of water entering a construction site.

(f) 

Control water on site. On the site, water must be controlled and kept to low velocities so that erosion is minimal. This can be achieved through immediate seeding and mulching or the application of sod, as well as the use of structural measures, including silt fences, check dams, mulch filter socks, and mechanical tracking of hillsides.

(g) 

Control sediment on site. Reduce the amount of sediment produced from areas of disturbed soils, and control the sediment produced on site through seeding and mulching and structural measures.

(h) 

Control sediment at the downslope site perimeters. Prevent the off-site transport of all sediment produced on the construction site using vegetated strips, diversion dikes, and swales, sediment traps and basins, stabilized construction entrances, and silt fences or mulch filter socks.

(i) 

Utilize biological or recyclable materials. To the extent possible, developers should utilize natural biological materials or recyclable materials as temporary measures that can remain on site after the completion of construction such as mulch berms or other methods, as opposed to silt fences, which must be removed and disposed of after the completion of construction activities in order to reduce waste and reduce costs of removal.

(j) 

Fill materials should be compacted sufficiently to be stable for their height and sufficiently strong to bear the weight of any structures they support.

(2) 

Design standards. The following standards shall be applied in planning for stormwater management and erosion control:

(a) 

Stormwater management and erosion control designs shall not conflict with minimum New York State Department of Environmental Conservation stormwater requirements or other environmental permits required.

(b) 

Measures shall be designed and installed to control the post-development average annual rate of runoff, as well as the average annual rate of runoff during each phase of construction so that it does not exceed average annual pre-development runoff. Average annual rate of runoff should be calculated using the Universal Soil Loss Equation.

(c) 

Emergency spillways and downslope drainage facilities shall have capacity to accommodate a one-hundred-year/twenty-four-hour storm.

(d) 

All measures in the plan shall meet, as a minimum, the best management practices (BMPs) set forth in the New York Standards and Specification for Erosion and Sediment Control.

(e) 

Stormwater management practices shall be selected to accommodate the unique hydrologic and geologic conditions of the site.

(f) 

The use of low-impact development techniques are preferred to intercept, treat, and infiltrate runoff from developed areas distributed throughout the site, as are techniques that restore, enhance, or protect natural areas such as riparian areas, stream channels, wetlands, and forests. Low-impact development techniques address stormwater through small, cost-effective landscape features located at the lot level and include items such as reducing the use of pipes, ponds, curbs and gutters; maintaining recharge areas, buffer zones, and drainage courses; using infiltration swales, grading strategies, and open drainage systems; reducing impervious surfaces and disconnecting those that must be used; and conserving open space.

(g) 

Stormwater management systems shall not discharge to surface waters, ground surface, subsurface, or groundwater within 100 feet of surface water within a water supply intake protection area.

(h) 

Any contiguous area of disturbance, not associated with the installation of a roadway, shall be limited to 20,000 square feet.

(i) 

Contiguous areas of disturbance shall be separated by at least 20 feet of area maintained at natural grade and retaining existing, mature vegetated cover that is at least 20 feet wide at its narrowest point.

E. 

Required submissions in stormwater management plans for application review. In addition to any information generally required by the City for subdivision or site plan application, the applicant must submit the following items to the Planning Commission for review:

(1) 

Existing and proposed conditions, including the following elements:

(a) 

Local map showing property boundaries.

(b) 

North arrow, scale, and date of plan and plan amendments.

(c) 

Surveyed property lines.

(d) 

Structures, roads, utilities, earth stockpiles, equipment storage, and stump disposal.

(e) 

Topographic contours at two-foot intervals.

(f) 

Critical areas relating to natural resources as defined at a regional level, state level, or local level by a regional, state, or local level natural resource inventory.

(g) 

Stockpile areas and staging areas.

(h) 

Within the project area, within 400 feet of the project boundary, and upgradient within the watershed or appropriate portions thereof, all surface waters, water bodies, streams, intermittent streams, ephemeral streams, wetlands, vernal pools, and drainage patterns and watershed boundaries.

(i) 

Vegetation, including description of species.

(j) 

Extent of the one-hundred-year floodplain, when applicable.

(k) 

Soil information from a soils survey soil series map or detailed site soil samples.

(l) 

Easements or covenants.

(m) 

Areas of soil disturbance or remediation areas.

(n) 

Areas of cut and fill.

(o) 

Areas of poorly or very poorly drained soils, including any portion to be disturbed or filled.

(p) 

Location of all structural, nonstructural, and vegetative stormwater management and erosion control BMPs.

(q) 

Detail sheet showing each BMP.

(r) 

Phasing plan.

(s) 

Inspection schedule.

(t) 

Construction schedule.

(u) 

Earth movement and grading schedule.

(v) 

Construction erosion and sediment control plan that complies with the provisions of this regulation.

(w) 

An operations and maintenance plan.

(x) 

Spill prevention plan and emergency management plan for spills of potentially hazardous materials.

(y) 

Surety.

(z) 

Identification of alternatives in the drainage system design that provide for contingencies during storm events, for instance, an alternative for water flow in case a critical culvert becomes blocked by debris.

(aa) 

Design calculations for all temporary and permanent BMPs and a narrative description of each measure, its purpose, construction sequence, and installation timing.

(bb) 

Drainage report with inclusion of more frequent small storms as well as traditional calculations.

(cc) 

Landscaping plan (unless required by other sections of the regulations).

(dd) 

Notation of soil types (unless required by other sections of the regulations).

F. 

Inspections.

(1) 

Inspections/frequency. Periodic inspections of stormwater management structures or techniques shall be conducted by the City Engineer or a qualified professional. At a minimum, inspections shall be conducted at the site prior to commencement of land-clearing activities, after every storm event during construction, periodically during construction, at the completion of construction activities and removal of any temporary BMPs, and as specified thereafter in an agreed-upon inspection schedule proposed by the developer in consultation with either the contractor who will build the project or a consulting contractor and approved by the Planning Commission and the City's Engineer, to insure that stormwater management structures or techniques are performing effectively.

(2) 

Inspections/documentation. All inspections shall be documented and written reports prepared by the City's Engineer or compliance consultant that contain the following information:

(a) 

Date and location of the inspection.

(b) 

Date of last storm event.

(c) 

Whether construction is in compliance with the approved stormwater management plan.

(d) 

Variations from approved construction specifications.

(e) 

Photographic documentation of each erosion and sediment control BMP and any other site level techniques employed pursuant to this regulation, such as but not limited to seeding of fill piles, marking of root zone areas of trees, disposal of construction debris, and implementation of any state- or federal-level recordkeeping or reporting procedures related to erosion and sediment control.

(f) 

Recommended actions for replacement, repair, or substitution of BMPs that are not functioning properly.

(g) 

Copies of reports and labeled photographs shall be provided to the Planning Commission.

(3) 

Phases of inspection. The schedule for inspections may include the following phases:

(a) 

Initial site inspection prior to plan approval, which shall include a site walk by the developer or developer's engineer and contractor, the City's Engineer and/or Code Enforcement Officer, and a member of the Planning Commission.

(b) 

Erosion control inspection to ensure erosion control techniques or structures have been properly installed, and are in accord with the developer's submitted plan.

(c) 

During and post-storm event inspection. The City Engineer shall inspect the site during and within 48 hours after the first storm event and subsequent storm events to ensure that erosion and sediment control techniques and drainage structures are functioning properly.

(d) 

Stormwater management system inspection. This inspection will include inspection of temporary measures to be employed only during construction, as well as semipermanent and permanent measures designed to remain for some time period after construction is completed but which may be completed before all construction of the site is completed. The inspector will also note whether construction debris is being disposed of properly and whether other erosion and sediment control measures in addition to those in the approved plan must be instituted by the developer to protect water resources.

(e) 

Final inspection and storm performance inspection. The City Engineer shall inspect the system after the system has been constructed and before the surety has been released. This inspection shall also evaluate the effectiveness of the system during and after the first actual storm. No surety will be released until the inspector certifies both the final inspection and the storm performance inspection.

(f) 

During inspections, or during other site visits by the City Engineer, if it is determined that the developer is not adhering to the approved erosion control plan, or that one or more of the erosion control techniques or structures installed are not operating properly, the City Engineer may issue a stop-work order. The stop-work order must provide specific reasons for its issuance, as well as to how the developer is to proceed to remediate the reasons for the order.