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Water Resource Protection through Stormwater Management and Pollution Control David Kubek, Senior Planner Central NY Regional Planning & Development Board Center fpr Watershed Protection, 2001 ---PAGE BREAK--- Why is stormwater management a concern? • Sediment and turbidity – Damages aquatic habitat – Impacts recreational resources • Phosphorus – Causes algal blooms, leads to anoxic conditions • Pathogens/bacteria – Can render waters unsafe for recreation • Potentially toxic substances: – Nitrogen – Metals – Oil and grease – Chlorides ---PAGE BREAK--- Why is stormwater management a concern? • Stormwater volume and flow – Impervious surfaces (pavement, rooftops, etc.) – Increased amount of runoff – Water can’t infiltrate into ground, so it flows more rapidly to streams and lakes – No opportunity for plant uptake or groundwater recharge • Consequences: – Flooding and erosion – Streams may dry up (no base flow from groundwater) ---PAGE BREAK--- Good stormwater management benefits municipalities • Prevent or lessen expenditures – Culvert replacements and road or bridge repairs – Maintenance of drainage structures • Minimize damage to water resources – Protect uses such as recreation and water supply • Reduce resident complaints about drainage issues – Reduce property damage ---PAGE BREAK--- Stormwater construction permit • Owners/operators of projects disturbing >1 acre must obtain coverage from NYS – This includes municipalities • Exemptions for highway construction – Road ditch maintenance, cleaning to maintain capacity – Road paving, resurfacing, and routine maintenance without sub-base disturbance – Stone road shoulder replacement – Restoration of sheet flow drainage at road edge ---PAGE BREAK--- Water quality standards violations • Turbidity (muddy character of water): “Substantial visible contrast to natural conditions” • Sedimentation that can be clearly traced to a given activity • Penalties up to $37,500 per day under NYS Environmental Conservation Law • Even projects that do not need permits must prevent these violations! ---PAGE BREAK--- Erosion control vs. sediment control • Erosion control – First line of defense – Prevent erosion through soil stabilization and runoff control – Easy, inexpensive, effective ---PAGE BREAK--- Erosion control vs. sediment control • Sediment control – Last line of defense – Remove sediment from water, trap it before it leaves site – Challenging, more expensive ---PAGE BREAK--- Erosion control vs. sediment control • Stabilize (seed and mulch) disturbed soil areas within 14 days – 7 days if >5 acres disturbed at once • Install sediment controls downslope of exposed soils and at points where runoff leaves site ---PAGE BREAK--- Erosion control • Roadside ditches can be a major source of sediment when not stabilized properly • Options include vegetation, erosion control fabric, or stone depending on grade and amount of flow ---PAGE BREAK--- Erosion control • Hydroseeding and Hydromulching road maintenance projects reduces runoff and erosion by promoting vigorous establishment of plant cover • County Soil and Water Conservation District may be able to assist with roadside hydroseeding ---PAGE BREAK--- Erosion control Insufficient application rate, or hydroseeding alone without mulch, may not be enough to stabilize soil. ---PAGE BREAK--- Sediment control • Catchbasin inlet protection – Numerous methods for existing paved streets – Best is concrete block inlet protection (accepted by NYSDEC) – Silt socks or catchbasin inserts should only be used if they have an overflow rim/opening (“sock” supported by bracketed ring) Not during active construction – Most other types clog and block inlets! – Sandbags may also cause ponding ---PAGE BREAK--- Sediment control • Outlet protection - use stone or other velocity-reducing material • Sizing of stone, placement, and shape of channel are important ---PAGE BREAK--- Sediment control • Stone check dams – Control velocity and erosion in steep roadside ditches – Capture and remove sediment ---PAGE BREAK--- Pollution Prevention and Good Housekeeping • Source control: Prevent exposure of pollutants to precipitation and runoff – Loading and unloading of materials – Minimize outdoor storage of potential pollutants – Vehicle and equipment maintenance – Parking areas for vehicles and equipment – Fueling operations – Petroleum product containment – Concrete washouts Photos courtesy of U.S. EPA ---PAGE BREAK--- Pollution Prevention and Good Housekeeping Photo courtesy of U.S. EPA • Owasco Inlet is on the 303(d) list of Impaired Waters for agricultural and urban sources of nutrients • Test soil and apply only the fertilizer that you need – Clean up any material spilled on pavement/sidewalk • During mowing, ensure clippings are directed toward the lawn – Keep clippings off impervious surfaces, out of waterways – Collect and compost if possible ---PAGE BREAK--- Pollution Prevention and Good Housekeeping Photo courtesy of U.S. EPA • Pet waste – Signage to encourage pet owners to clean up waste – Provide bags for disposal in trash • Wildlife waste – Restrict mowing around open water – vegetated buffer – Signs to discourage feeding • Owasco Lake is on the 303(d) list of Impaired Waters for pathogens from wildlife waste and other sources ---PAGE BREAK--- Drainage system maintenance • Catchbasin cleaning and street sweeping – Prioritize by proximity to waterways and sediment sources • Road ditch/swale maintenance – Immediate stabilization with vegetation or stone is critical – Work in dry weather only • Spoils disposal – Avoid stockpiling where erosion to stream or drainage system may occur, or stabilize/protect pile – Representative sample to determine if hazardous waste ---PAGE BREAK--- Post-construction stormwater maintenance Settling basin in good condition Settling basin that has not been cleaned • Stormwater pond settling basins must be dredged when the sediment accumulates to 50% of the basin (“forebay”) capacity • Otherwise, sediment enters main pool and can be carried out of pond ---PAGE BREAK--- Post-construction stormwater maintenance • Erosion of side slopes and embankments must be repaired • Aquatic bench (wetland vegetation on shallow shelf around edge of pond) must be maintained. Slope failure, no aquatic bench Well-maintained berm and aquatic bench ---PAGE BREAK--- Post-construction stormwater maintenance • Water quality swales and detention areas must contain dense vegetation • Eroded areas should be repaired when identified ---PAGE BREAK--- Non-stormwater connections • Illicit discharges are identified in several ways – Visual indicators (obvious pollutants emitted from stormwater outfalls – color, odor, appearance) – Occurrence of flow from stormwater outfall during dry weather – Other indicators – deposits, flows, algal growth, unidentified connections to stormwater conveyances – Track back through system to find and eliminate source – e.g. sewage, floor drains, washwater, dumped chemicals ---PAGE BREAK--- Land use regulations used to address stormwater issues • Comprehensive plans – Determine land use and community character • Low impact development – Permanent preservation of natural features in a development • Zoning – Environmental protection overlay districts – Performance zoning – Special use permits – Incentive zoning – Cluster development ---PAGE BREAK--- Land use regulations used to address stormwater issues • Local laws – Open space preservation – Water resource protection – Wetland preservation – Stormwater management Erosion and sediment control Illicit discharge prohibition • Planning board approvals – Subdivision Review – Site Plan Review – State Environmental Quality Review (SEQR) ---PAGE BREAK--- • Reduction in initial stormwater runoff – Less water to deal with – Less chance to carry pollutants • Storage and uptake of stormwater near source – Volume control • Pollutant removal = water quality improvement • Uses: – Stormwater treatment – Combined Sewer Overflow (CSO) abatement – Correction of sanitary sewer inflow/infiltration Water resources benefits of green infrastructure ---PAGE BREAK--- Other benefits of green infrastructure Community aesthetics and quality of life NYS Stormwater Management Design Manual, 2010 Air quality improvement Energy savings Mitigation of urban heat island effect Water conservation Carbon sequestration Habitat Education Source: Onondaga County Save the Rain Program Source: Onondaga County Save the Rain Program ---PAGE BREAK--- Types of green infrastructure These are green infrastructure practices… • Tree planting • Rain gardens • Bioswales • Rain barrels • Green roofs • Pervious pavement • Stormwater planters Source. EPA NYS Stormwater Management Design Manual, 2010 Source: Onondaga County Save the Rain Program ---PAGE BREAK--- Types of green infrastructure But these are also forms of green infrastructure… • Soil restoration and amendment • Vegetated riparian buffers • Wetlands • Floodplains • Filter strips • Natural drainage systems • Natural vegetation and forested areas ---PAGE BREAK--- Vegetated buffers • Buffers along streams and lakes have numerous benefits – Prevention of bank erosion – Filtration of pollutants – Discourage pest waterfowl from lingering – Habitat for other types of wildlife • Use native shrubs and trees tolerant of periodic inundation – http://www.dec.ny.gov/docs/water_pdf/swdmappendixh.pdf contains a good listing ---PAGE BREAK--- Types of green infrastructure Rain gardens and bioretention • Downspout disconnection to rain gardens • Simple and inexpensive to install • Parking lot or street runoff to bioretention • Bioretention underdrain creates a filter for heavier pollutants ---PAGE BREAK--- Types of green infrastructure Rain barrels and cisterns • Water can be re-used for non-potable purposes Downspout disconnection • Allow water to soak into soil • Prevent contact with pollutants and lessen load on drainage system ---PAGE BREAK--- Types of green infrastructure Pervious pavement • Porous asphalt and concrete • Paver blocks • Permeable soil and stone layer critical ---PAGE BREAK--- How can green infrastructure be used to solve stormwater problems? • Keep water out of the sewer system • Delay flow into the system • Remove runoff through plant evapotranspiration • Pollutant treatment – filtration and infiltration • Caution: It’s not always the – Entire solution – Only solution – Best solution! • But: – It’s often part of the solution! Source: City of Seattle Public Works Source: Low Impact Development Center, Inc. ---PAGE BREAK--- CNY RPDB Green Infrastructure Program • We can provide the following services (with municipal input throughout the process): – Preliminary evaluation of water quality or flooding problems and/or green infrastructure opportunities – Initial site identification and characterization – GIS Analysis – Detailed site visit – Assessment of options and potential locations – Concept sketch(es) of proposed solution(s) ---PAGE BREAK--- Questions? David Kubek, Senior Planner Central NY Regional Planning & Development Board 126 N. Salina St., Suite 200 Syracuse, NY 13202 (315) 422-8276 x211