Principles Of Stormwater Management- Minimizing Stormwater .
Principles of Stormwater ManagementMinimizing Stormwater RunoffPollution from Your ProjectPresentation at Virginia Tech forNutrient Management TrainingVirginia Cooperative Extension In ServiceVirginia Department of Conservation and RecreationNovember 14, 2012David SampleAssistant ProfessorBiological Systems EngineeringApril 9, 20081
Urban Stormwater at VT Adaptive management in design andoperation of BMPs Education for Virginia municipalstormwater personnel Evaluating life-cycle costs of LID Establishing water-quality testingprotocols for new BMPs Design/construction of new or enhancedBMPs7. FinalDesign,ConstructSystem8. Operateand MaintainSystem6. Size and DevelopConceptual Design ofTreatment SystemsMonitor SystemsEvaluate Performance,EffectivenessRefine DesignsRetire/Replace1. ProblemDefinition9. Adaptive Management5. Assess/RefineTreatment Systems4. Select TreatmentSystem Components3. Identify ApplicableFundamental TreatmentUnit Processes2. SiteCharacterizationIdentify Constraints2
Activities/Examples of Extension Products General Public audience 16-part Fact sheet series BMP Fact sheets series:http://pubs.ext.vt.edu/author/s/sampledavid j-res.html Mid-Level audience Chapter 12 in Urban NutrientManagement Handbook (w/ L. Fox) http://pubs.ext.vt.edu/430/430350/430-350.html Basis of training for ANR Agents,proposed in-service 1/133
Professional Audience/ServiceBMP Clearinghouse: Reviews all BMPs VTAP Verify MTDs VTAP - to be approved 2012 Will continue as TechnicalEvaluator in 2013 VA BMP Clearinghouse:http://vwrrc.vt.edu/swc/Other Service: Chesapeake Bay STAC ASCE Urban Water CouncilPublic BenefitSample, D.J., Grizzard, T.J., Sansalone, J., Davis, A.P., Roseen, R.M., Walker, J., 2012. Assessing performance of manufactured treatment devices forthe removal of phosphorus from urban stormwater. Journal of Environmental Management, 113, pp. 279-291, doi: 10.1016/j.jenvman.2012.08.039.
Floating Treatment Wetland Research Retrofit of existing wetpond Heavily urbanizedheadwatercatchment NFWF/Ches. Bay Fund
Low Impact Development-LID Developing a designmodel Evaluating it in simplemesocosms Then will apply it to fullscale
OutlineUrban Impacts and Effects on Water Quality ofStormwater – Review of concepts Imperviousness Quality, Quantity Impacts to Streams & receiving watersWhat are we doing about it? Runoff Reduction Method, LID practices Rain Gardens (aka bio-retention basinsConstruction, maintenance, site study, soils)
Urban Impacts and Effects on Water Quality8April 9, 2008
What happens to the Rain? Depends on many factors: Rate of rainfall Soil conditions (Dry, Damp,Soggy) Density of vegetation Amount of urbanization TopographyMichigan Tech, 2009. Michigan Environmental Education Infiltration.html9April 9, 2008
What is Stormwater? Water that is notreabsorbed into theground. Rain/Sleet Melting Snow / Ice Irrigation10April 9, 2008
Where does Stormwater Go? Not to a Treatment Plant,directly into our streams,rivers, lakes, bays, andreservoirs Infrastructure: Blue/Black/Gray/Green11April 9, 2008
What is a Watershed? A watershed is the land that water flows across on itsway to a stream, river, or lake. Water either goes into the soil or flows overlandSource: Potomac Conservancy (2007) State of the Nation’s River. Symbols courtesy of the Integration and Application Network (ian.umces.edu/symbols, University of Maryland Center for Environmental Science.12April 9, 2008
Stormwater is not typically an issue inundisturbed areas Leaves of trees and plantsbreak up the raindrops Roots of plants and healthysoil absorb water Because of plant cover,fewer soil particles arecarried along as it travelsdown the watershed to abody of water.13April 9, 2008
When is Stormwater an Issue? Disturbed areas(lackingvegetation) causeserosion Impervious surfaces(pavement/buildings)causes increasedrunoff14April 9, 2008
Stormwater Quantity-Peak RunoffPre-developmentPost-development w/o stormwater controlPost-development w/stormwater controlStreamDischargeTimeSources: Tess Wynn, “Low Impact Development”, 2009, Biological Systems Engineering, Virginia Tech15April 9, 2008
Stormwater Quantity: Impacts on VirginiaHydrologic CycleETRunoffShallow 1323Source: State of the Nation’s River 2008, Potomac Stormwater Runoff, Potomac Conservancy.16April 9, 2008
Stormwater Quantity:Stream MorphologySource: Metropolitan North Georgia Water Planning District (2003) District-Wide Watershed Management Plan17April 9, 2008
Stormwater Quality: Sources of Pollutants inWatershedsPoint SourcesNonpoint Sources Defined and discretedischarge point Examples: Industrial,Cooling water, DomesticWastewater Diffuse sources Usually occur in wetweather Difficult to control andregulateSource: Left – Rutgers University; Right – Biological Systems Engineering, Virginia Tech18April 9, 2008
Currently Impaired Waters in VirginiaSource: VDEQ Final 2008 305(b)/303(d) Water Quality Assessment Integrated Report19April 9, 2008
Chesapeake Bay IssuesSource: Chesapeake Bay Report Card, 2008, Integration and Application Network, University of Maryland Center for Environmental Science (UMCES) and EcoCheck, apartnership of National Oceanographic and Atmospheric Administration (NOAA) and UMCES.20April 9, 2008
What are we doing about it?Managing Urban Stormwater
Tributary Strategies-P Loads8Median Total Phosphorus Load (lb/ac-year)7ExcludingNurseries6543210Conventional Conventionalcropcrop withoutreceivingmanuresmanureAlfalfaHay mperviousBaredeveloped constructionExtractiveLand UseSource: EPA (2008) Chesapeake Bay Model support documents22April 9, 2008
Tributary Strategies-N Loads30ExcludingNurseriesMedian Total Nitrogen Load (lb/ac-year)2520151050Conventional Conventionalcropcrop withoutreceivingmanuresmanureAlfalfaHay mperviousBaredeveloped constructionExtractiveLand UseSource: EPA (2008) Chesapeake Bay Model support documents23April 9, 2008
Urban Nutrient BudgetPhosphorusNitrogen24April 9, 2008
Municipal Stormwater Programs-Bay Wide Municipally Separate StormSewer Program (MS4)regulated under CleanWater Act/NPDES All jurisdictions subject toTMDL Phase 1 (large, previouslypermitted, requiredmonitoring) Phase 2 (Medium sized,newly permitted, nomonitoring required)Source: EPA (2010) Draft TMDL for the Chesapeake Bay.25April 9, 2008
Municipal Stormwater Programs Next phase ofTMDL-allocation tojurisdictions26April 9, 2008
Virginia Stormwater CriteriaExistingProposedBased upon Peak RunoffControl: Water Quality Volume-1inch/30 hours Channel Protection, 1year storage for 24hours & evaluatevelocity at 2-year,conveyance at 10. Flood protection, 10yearBased upon an Iterative LandDevelopment Process: Environmental SiteDesign- minimizeimpervious surfaces Runoff ReductionIncrease infiltrationthrough LID Pollutant Removal-Treatremaining runoff toremove Phosphorus Potential Channel “work”to remain constantVirginia Stormwater Management Handbook (1999), graphic from GeorgiaStormwater Manual (2001)Source: Technical Memorandum: The Runoff ReductionMethod, April 18, 2008, Center for Watershed Protection27April 9, 2008
Proposed 3-step Strategy1. Environmental Site Design2. Runoff Reduction3. Pollutant RemovalCriteria: 0.41 lb/acre/year Ploading from sitethrough ESD, RR, PR Equivalent to forestedconditions Redevelopment set at20% improvement28April 9, 2008
Conventional Site DesignThe “Good Drainage” ParadigmSource: Prince Georges County, MDAdapted from David J. Hirschman, City ofAprilWinchester– 299,2008Watershed Management Workshop, April 27, 2005
Collect, Convey, Concentrate, Centralized TreatmentConventionalDevelopmentSource: Prince Georges County, MD30–Adapted from David J. Hirschman, Cityof WinchesterApril9, 2008Watershed Management Workshop, April 27, 2005
Distributed, Disconnected, DecentralizedLow ImpactDevelopment /EnvironmentalSite DesignSource: Prince Georges County, MDAdapted from David J. Hirschman, City ofAprilWinchester– 319,2008Watershed Management Workshop, April 27, 2005
Source: Prince Georges County, MDAdapted from David J. Hirschman, City of Winchester –Watershed Management Workshop, April 27, 200532April 9, 2008
Best Management Practices
#1-Impervious Surface Disconnection (RR) Redirects rooftop runoff fromimpervious to pervious areas Practice can be used alone(large lot, permeable soils), orin combination Most economical practiceavailableN RemovalP Removal0%20%40%60%80%100%Average Annual Removal Rate34April 9, 2008
#2-Sheetflow to Open Space (RR, PR) Also known as filterstrips/vegetated filter strips Small flows, larger flows canbe accommodated with alevel spreader Reduces velocity, ageAnnual Removal Rate80%100%35April 9, 2008
#3-Grass Channels (RR, PR) Open channels, grassed Treatment via filtering, nomedia LID conveyance system No storage, velocity is sloweddue to roughnessNRemovalPRemoval0%20%40%60%AverageAnnual Removal Rate80%100%36April 9, 2008
#4-Soil Restoration (ESD, RR) Amending soils with compost Improves: Soil structure Infiltration Rooting/Water holdingcapacity Reduces compactionN RemovalP Removal0%20%40%60%80%100%Average Annual Removal Rate37April 9, 2008
#5-Vegetated/Green Roofs (RR) Designed to provide modeststorage Converts some water to ET Reduces Energy Loss/LEEDS Aesthetically pleasing Typically addresses smallstorms, .25-0.5 inches Extensive-Intensive Ex: SunTrust Bank, RichmondNRemovalPRemoval0%20%40%60%AverageAnnual Removal Rate80%100%Source: Richmond Regional Planning and Development Council at r/green roof.htm38April 9, 2008
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#6-Rainwater Harvesting/Cisterns (RR) Captures imperviousrunoff Underground/Above Reuse-can be Outdooror indoor Supplements watersupply Volume benefitsmaximize if managed Removal: 40% P, NSource: Virginia Rainwater Harvest Manual, at www.CabellBrandCenter.org andWSSI/Wetland Studies and Solutions, Inc., at http://www.wetlandstudies.com.40April 9, 2008
#7-Permeable Pavement (RR) Paver/block systems Porous concrete Provides storage by eliminating use of finematerials Heavy traffic areas maynot be suited Must keep sediment off! Reduce/attenuates small storm runoffdepending upon substrateNRemovalPRemoval0%20%40%60%AverageAnnual Removal Rate80%100%Source: William Hunt’s web site at www.bae.ncsu.edu/stormwater and WSSI/WetlandStudies and Solutions, Inc., at http://www.wetlandstudies.com/41April 9, 2008
#8-Infiltration Basins (RR, PR) Provides storage within voids Surface can be used for passivestorage Provides RR (if soil permits),attenuation, and PR Must be careful to avoid perviousrunoff Maintenance costs ual Removal Rate80%100%Source: www.stormwatercenter.net, and WSSI/Wetland Studies and Solutions, Inc., at http://www.wetlandstudies.com.42April 9, 2008
#9-Bioretention/Rain Gardens (RR, PR) Aka “Rain Gardens”With and without UnderdrainsPeak/Volume BenefitsPollutant RemovalIssues: Keep Small (5-10%) DA Sediment Pretreatment l Removal Rate80%100%Source: www.stormwatercenter.net, William Hunt’s web site at www.bae.ncsu.edu/stormwater, andWSSI/Wetland Studies and Solutions, Inc., at http://www.wetlandstudies.com Rain Gardens in Virginia: TechnicalGuide (2009) Virginia Department of Forestry and ape.pdf.43April 9, 2008
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#10-Dry Swales (RR, PR) Provides temporary storageand filtering “Linear bioretention” High nutrient removal rates,economicalN RemovalP Removal0%20%40%60%80%100%Average Annual Removal Rate45April 9, 2008
#11-Wet Swales (PR) Similar to “roadside swales,however much larger Vegetation/wet pool providesWQ treatment Not recommended and steepslopes Lower capital cost, highermaintenance costsN RemovalP Removal0%20%40%60%80%100%Average Annual Removal Rate46April 9, 2008
#12-Filtering Practices Provides temporarystorage of flow events Nonbypassed flow istreated through a mediafilter LOTS of different mediadesignsN RemovalP Removal0%20%40%60%80%100%Average Annual Removal Rate47April 9, 2008
#13-Stormwater Wetlands (PR) Provides excellent nutrientremoval Must have continuous base flow Large land area required Low maintenance New focus on emergent andforested wetlandsN RemovalP Removal0%20%40%60%80%100%Average Annual Removal RateSource: www.stormwatercenter.net, and William Hunt’s web site at www.bae.ncsu.edu/stormwater48April 9, 2008
#14-Wet Ponds (PR) Provides nutrient and sedimentremoval Can provide flood control benefits Must have base flow Maintenance can be high Discharge energy can be problematicN RemovalP Removal0%20%40%60%80%100%Average Annual Removal RateSource: Georgia Stormwater Manual (2003),http://www.unh.edu/erg/cstev/fact sheets/ret pond fact sheet 08.pdf49April 9, 2008
#15-Extended Detention Pond (PR) Dry detention that provides12-24 hours detention duringrunoff events Good sediment removal, andnutrients that are associatedwith sediment Lowest efficiency of allpracticesN RemovalP Removal0%20%40%60%80%100%Average Annual Removal Rate50April 9, 2008
What About costs? Consider Life Cycle and Performance Cost tiers Tier 1-Lower End Rainwater Harvesting Dry swales Extended Detention ? Tier 2-Middle Range Wet swales Wet ponds ? ? Tier 3-Upper End Vegetated Roofs ?51April 9, 2008
What About Costs? Tier 1-Lower End Rainwater Harvesting Dry swales Extended Detention Rooftop disconnect Sheetflow/filter strip Grass Channel Tier 2-Middle Range Wet swales Wet ponds Tier 3-Upper End/Specialized Vegetated Roofs Soil restoration Infiltration Practices Bioretention Stormwater wetlands Permeable pavement52April 9, 2008
What About Costs? Tier 1-Lower End Rainwater Harvesting Dry swales Extended Detention Tier 2-Middle Range Wet swales Wet ponds Tier 3-Upper End/Specialized Vegetated Roofs Soil restoration Rooftop disconnect Sheetflow/filter strip Grass Channel Infiltration Practices Bioretention Stormwater wetlands Permeable pavement53April 9, 2008
Dave Sam p les’ Pub licat ionsRooftop 6-120 128/426-128 pdf.pdfRainwater Harvestinghttp://pubs.ext.vt.edu/BSE/BSE-6/BSE-6 pdf.pdfVegetated Roofshttp://pubs.ext.vt.edu/BSE/BSE-6/BSE-6 pdf.pdfGrass Channelshttp://pubs.ext.vt.edu/BSE/BSE-6/BSE-6 pdf.pdf54April 9, 2008
Ok, but I only manage a single residential lot.What can I do?Stormwater Management for Homeowners
Develop a Site Plan Identify location of imperviousareas and where they drain Identify slopes Characterize soils Identify landscaping/vegetation Identify sensitive areas (creeks,ditches, lakes, wetlands, steepslopes, inlets) Identify paths of runoff and benice to your neighbor.remember where doesstormwater go?56April 9, 2008
Key questions Can you change your site layout to reduce runoff?Are yard and garden wastes kept away from runoff?Do you use and handle chemicals safely?Do you store fertilizers, pesticides and chemicals indoors?Do you fertilize in the fall or spring?How do you manage car/truck waste?How do you handle pet waste?Do you use salt/deicing products?Are there bare soil areas around your home?How is roof water directed (onto pervious or impervious areas)? Can you reduce paved surfaces or try permeable pavement?57April 9, 2008
Residential BMP#1-Modify Site Layout Can you find ways to: Modify flow paths, make them longer Restore soils where they havebecome compacted Terrace steep slopes Consider “Good sense” practices: Rain gardens Buffer strips, especially riparian Consider opportunistic practices Permeable pavement driveways Green roofs58April 9, 2008
Residential BMP#2-Manage YourYard/Garden Waste Start a compost pileUse a mulching mowerSweep up yard wastePlanting in dry periodsMulch bare soilsIf Municipality provides leafcollection, time your sweep!59April 9, 2008
Residential BMP#3-Smarter Irrigation Avoid overwatering/don’t let it die Get a rain gage Use irrigation timer/controller to setrate, rain cut off Install soil moisture sensors Advanced designsinclude ET sensors60April 9, 2008
Residential BMP#4-Handle Chemicals Safely Choose native, hardy plantsWeed by handUse pesticides as a last resortAvoid fertilizer/pesticide usenear water or after rain Spot treat with pesticides Sweep up any residue anddispose of properly. Follow any pesticide label-it’sthe law!61April 9, 2008
Residential BMP#5-Store Chemicals Indoors Store materials inside, cover with atarp, or remove materials Limit the exposure of potentialpollutants to rainfall or runoff . Minimize the amount of materialstored by implementing “just intime” purchasing Dispose of spent materialsproperly-”Household HazardousWaste Day”62April 9, 2008
Residential BMP#6-Use FertilizersAppropriately Fertilizer is wasted if not needed To assess need, test soils-VTCSES lab every 3 years Likely should fertilize in the fall,not spring P content of most soils is manytime what is needed Measure your lawn Use the correct amount Join programs like PWC Great‘Scapes63April 9, 2008
Residential BMP#7-Manage Vehicle WasteAppropriately Wash your car on the grass or carwash Use phosphate-free car soaps Maintain your vehicle to preventleaks Use kitty litter or saw dust to cleanup leaks and spills-landfill Collect and recycle hazardouswaste oils, solvents etc. andproperly dispose of auto fluids64April 9, 2008
Residential BMP#8-Handle Pet WasteAppropriately Always pick up after your petand dispose of the wasteproperly Yes, the back yard too. Much of the P leaches in 2days Seal it in a plastic bag andthrow it away Farmettes-compostingsystems65April 9, 2008
Residential BMP#9-Use Deicing ProductsAppropriately Clear snow to the lower endof paved areas. Clear snow from drains toallow for better drainage Mix salt with sand forgreater safety andeffectiveness, limit impact Alternatives include kittylitter, cinders, ashes—Notfertilizer!66April 9, 2008
Residential BMP#10-Repair Bare Soil Areas Plant vegetative buffers Plant groundcovers using nativeplants Re-seed bare spots or mulch Use silt fences during projects67April 9, 2008
Residential BMP#11-Disconnect Downspouts Disconnect gutters,drain onto vegetatedareas Consider connectingto rain garden orcistern Consider soilrestoration in path Exercise care aboutfoundations68April 9, 2008
Residential BMP#12-ReducingImperviousness Minimize Pavement Low tech-Two track driveway Consider permeable pavement(with reservoir) Install swales, grasschannels Install cisterns or raingardens69April 9, 2008
Residential BMP#13-Manage Solid WasteAppropriately Use storage containers, recyclematerials in separate container If no collection, bin itemsseparately Home renovation waste-cover70April 9, 2008
Residential BMP#14-Limit Pressure Washing Limit pressure washing ofpavement, buildings Find means of collectingwastewater generated71April 9, 2008
Residential BMP#15-Manage Septic SystemsIssue Low cost treatment of choice if sewer unavailable Septic Systems are a major, essentially unmanagedcontribution of Nitrogen loading to receiving waters Fecal coliform NOT an issue unless SystemmalfunctionsSolutions Inspect and maintainperiodically Advanced TreatmentSystems72April 9, 2008
Residential Lot Stormwater Ma
Establishing water-quality testing protocols for new BMPs Design/construction of new or enhanced BMPs . Urban Stormwater at VT . 1. Problem Definition 2. Site Characterization Identify Constraints 3. Identify Applicable Fundamental Treatment Unit Processes 4. Select Treatment System Components 5.
NPDES: Stormwater Best Management Practice— — Stormwater Wetland Stormwater Retrofit A stormwater retrofit is a stormwater control (usually structural) that a community puts into place after development to improve water quality, protect downstream channels, reduce flooding or meet other specific objectives.
Pennsylvania Stormwater Best Management Practices Manual December 2006 Stormwater Best Management Practices Manual Cover and Table of Contents Chapter 1 - Introduction and Purpose Chapter 2 - Making The Case For Stormwater Management Chapter 3 - Stormwater Management Principles and Recommended Guidelines
Green Stormwater Infrastructure Maintenance Manual 7 1.1 Introduc on The City of Philadelphia relies in part on Green Stormwater Infrastructure (GSI) systems—comprised of one or more decentralized stormwater management prac ces (SMPs) such as rain gardens, stormwater tree trenches, and green roofs—to reduce stormwater volume and pollutants
Green Stormwater Infrastructure Maintenance Manual 7 1.1 Introduc on The City of Philadelphia relies in part on Green Stormwater Infrastructure (GSI) systems—comprised of one or more decentralized stormwater management prac ces (SMPs) such as rain gardens, stormwater tree trenches, and green roofs—to reduce stormwater volume and pollutants
1.3 New Jersey Stormwater Best Management Practices (BMPs) Manual The New Jersey Stormwater Best Management Practices Manual (BMP Manual) of April 2004, as amended, was developed to provide guidance to implement the standards in the Stormwater Rules. The BMP manual provides examples of ways to meet the standards required by the Stormwater R
The Clark County Stormwater Manual: Book 4 - Stormwater Facility Operations and Maintenance is adapted from the Clark County Stormwater Facility Maintenance Manual, 2009 and the Stormwater Management Manual for Western Washington, Volume V, (Ecology, 2019). Illustrations are courtesy Washington Department of Ecology or redrawn from Washington
Stormwater Management Plan Best Management Practices This Stormwater Management Plan groups stormwater best management practices according to permit requirements into the following sections: 1. Illicit Discharge Detection and Elimination . 2. Industrial and Commercial Facilities . 3. Construction Site Runoff Control . 4. Education and Outreach . 5.
Mar 03, 2020 · “Design Manual” - The 2006 Pennsylvania Stormwater Best Management Practices Manual, as revised from time to time, which serves as the official guide for Stormwater Management principles, methods, and practices in Pennsylvania. “Developed” – Property where man-made changes have been made which add impervious
