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Home My WebLink Aboutswhandout1 Managing storm water runoff and its impacts is a serious issue facing Iowa and the llation~ State and federal governments mandate local storm water programs to control storm water pollution. The intent of these regulations is to improve ,vater quality by reducing storm water runoff and the contaminants carried by storm water. " WHAT" IS S-T"ORM WATER RUNOFF? Storm water runoff is rainfall or snowmelt that runs off pe"rmeable surfaces or impervious surfaces like roads, buildings, sidewalks or compacted ground surfaces. It can drain directly into streams, rivers and lakes by traveling over ground or through storm drains. These drains, commonly called storrrt sewers, should not be confused with sanitary sewers that transport wastewater to a treatment plant before discharg- ing to surface" waters. Storm water entering storm sewers does not receive any treatment before it flows to surface waters such as lakes and streams~ THE PROBLEM Contami~ants in storm water runoff that flow through municipal storm sewers "may impact drinking water sources, recreational waters and aquatic life. Storm water problems are often most evident in urban areas. As communities grow, they often experience more storm water runoff problems due to their in- creasing impervious areas. Impervious areas reduce the amount of rainwater that can naturally. infiltrate into the soil. This causes an increase in the volume and rate of storm water runoff. It can lead to more frequent and severe flooding, stream " bank erosion; and potential damages to public and private property and water" quality. PRINCIPLES OF STORM" WATER MANAGEMENT The traditional approach to storm water management drains runoff water off- site through pipes and storm sewers as quickly as possible. Traditional detention- based storm water systems only manage the large storm events for flood" control and generally do -not provide water quality protection. This approach does not minimize the amount of runoff generated or prevent or reduce the pollution to the receiving water body. The ~ncreased volume and duration of flows can cause ,vater quali1;y and quantity "issues including stream bank erosion and prqperty damage. Today, more comprehensive storm water management is needed. Storm water lllllst be managed for both flood control and wate"r quality protection~ Infiltration-based storm water management practices are the key to a more comprehensive approach. Infiltrating small rains and the first flush of larger storms minimizes the amount of runoff generated and the pollutant loads that are delivered to surface waters. Ru"noff must be managed to protect water quality in cost effective ways A Site planning t.hal uses more natural ways to infiltrate or convey rainfall can save money over traditional pipe and detention-based systelTIs. It can also reduce costs associated with long-term main- tellance of infrastructure~ STORM WATER POLLUTANTS AND SOURCES INCLUDE:. · . Sedi.ment from construction sites,. .. streamba~k erosion, disturbed areas .. .. . ... Pesticides and fertilizers from lawns, .:. :. . parks and.roadsides. .... .. Bacteria from pet wastes and septic.. . systems. .. ..". .. . · Nutrients from .lawn.fertilizer. · Oil and grease from car leaks, gas. .. . stations and industrial areas · Road salt and sand from snow and ice control applications · Carelessly discarded trash such as cigarette. butts, paper wrappers. and . plastic. bottles · Illicit connections to storm sewers .. · ..llIegally dumped pollutants. · Thermal impacts from sun-heated. . . . impervious surfaces transferring heat. . . to.. rainfall runoff .. FEDERAL ROLE AND REGULATIONS: NPDES STORM WATER PROGRAM The federal Clean V\Tater Act (CWA) is the primary basis for all federal and state water quality programs~ The CVVA was enacted vvith a goal of making all U.S. V.faters fishable and swimmable. The CWA established the Environmental .Protection Agency's (EPA) National Pollutant Discharge Elimination Sy~tem (NPDES) pro- gram to control water pollution by regulating sources that discharge pollutants into waters~ The EPA set standards for federal water quality prograIlls and assures that state pro- grams are operating in accordance -with the . federal -guidelines.. In IoV\ra, the Iowa Departnlent of Natllral Resources (DNR) is autllorized by tlle EPA to administer the NPDES program and issues permits for starnl water discharges subject to permit requirements. I.OWA COMMUNITIES IMPLEMENTING Marshalltown Ames. . Iowa State University- Storm Lake . Carter lake Council Bluffs Waterloo <:> <:) - Des Moines .Ottumwa MUNICIPAL STORM WATER PERMITS AND REGULATIONS Phase I of the storm water permitting process relied on NPDES permit coverage to improve. the quality of storm water runoff. Larger municipalities with separate storm sewer systems (MS4s) were. included in Pllase I regulations. Des Moines and Cedar Rapids '^lere. the only Iowa cities required to obtain a permit to discharge storm water under the P11ase I program. . Effective in 2003, NPDES Phase II required that 41 more Iowa communities and tvvo universities obtain permits and -strive to improve storm water quality~ The permit requires that each ccnnmunity develop and implement a comprehensive storm water quality management program. Maps are not to scale. PHASE II REGULATIONS SIX NEW REQUIREMENTS FOR IOWA COM.M UNITIES To reduce nonpoint source pollu- tion, Phase II cities are required to de- velop a program that addresses six main areas. These programs. should significantly . reduce water pollution associated vvith urban runoff 1. Control erosion and retain sediment on construction sites. 2. Improve storm water management to control flooding and protect water quality. 3~ Inspect storm drain outlets regularly to detect and .eliminate any illicit discharges~ 4~ Implement "good housekeeping" practices to ensure municipal operations are not contributing to water quality degradation. 5. Educate residents 110w to contribute to water quality protection. . 6. Involve the public in implementing the city's plan for protecting water quality. PERMITS FOR LAND DISTURBING ACTIVITI ES Land disturbing activities at construc-. tion sites often contribute large amouilts of sediment to aqjacent streams and lakes. NPDES Phase II regulations address urban construction activities througllout Iav/a, evel1 at sites not located ill Pl1ase II com- munities. Those involved in COl1struction . activities disturbing one or more acres of land require an NPDES permit and development and implemen tation of a. storm vlater pollution prevention plan (SWPPP) for the site. A key component of the SWPPP is to identify practices that reduce erosion arid prevent sediment loss from construction sites~ INDUSTRIAL STORM WATER PERMITS Many industrial activities and facilities also require permits and SWPPPs. Permitted industrial activities include manufacturing, transportation, oil and gasJ hazardous waste and other facilities. Also included are some governmental facilities including landfills, airports and wastewater treatment plants. Iowa Stormwater Education Program in cooperation with the Iowa Stormwater Partnership Pat Sauer: (515) 289-1999 W\^lW. iowas to rmwater. 0 rg Iowa Department of Natural Resources Joe Griffin, Program. Coordinator: (515) 281-7017 W\^lW.iowadnr.com/water / stormwater / U.SA El1vironmental Protection Agency Stormwater Program W\^lW.epa.gov / ebtpages/watestorrnwater.html Iowa Statewide Urban Design and Specifications (SUDAS) W\^lW.iowasudas.org This publication was created by - The Iowa Stormwater Education Program in cooperation with . The Iowa Departme.nt of Natural Resources 2005 -