Introduction to Urban Stormwater Introduction to Urban Stormwater

Charles Humphrey Jr.Area Environmental Agent

North Carolina Cooperative Extension

Charles Humphrey Jr.Area Environmental Agent

North Carolina Cooperative Extension

Water Cycle in Open and Urban Water Cycle in Open and Urban AreasAreas

Urban Stormwater PollutantsUrban Stormwater Pollutants Common Stormwater Best Common Stormwater Best

Management PracticesManagement Practices SummarySummary

Percolation

Water CycleWater Cycle

Water CycleWater Cycle

Urban Water CycleUrban Water Cycle

What is a Watershed?What is a Watershed?

(Osmond, 2000)

Intended Uses of Intended Uses of Water ResourcesWater Resources

SwimmingSwimming BoatingBoating FishingFishing Drinking water for Drinking water for

humanshumans Drinking water for Drinking water for

animalsanimals Aquatic life habitatAquatic life habitat

Stormwater Stormwater Pollutants/ConcernsPollutants/Concerns

Nutrients- nitrogen and phosphorus can lead to

eutrophication and fish kills

Sediment- clogs drainage ways,

clouds rivers and degrades aquatic

habitat

Bacteria- public health risk, can lead to closure of fishing areas and loss of revenue

Over 1150 acres of NC shellfish waters have been closed since 1990 mostly due to stormwater runoff

Water- flash floodsWater- flash floods

Stormwater RegulationsStormwater Regulations

Address water quantity and water Address water quantity and water quality leaving developed sitesquality leaving developed sites Water quantity- design practices to Water quantity- design practices to

detain first 1” to 3.5” of stormwater detain first 1” to 3.5” of stormwater from sitefrom site

Water quality- reduce transport of Water quality- reduce transport of nutrients and sediment to receiving nutrients and sediment to receiving waterswaters

Stormwater Best Stormwater Best Management Practices Management Practices

(BMPs)(BMPs)

Types of Structural Types of Structural BMPsBMPs

Wet Ponds Stormwater Wetlands Bio-retention Areas/ Rain

Gardens Permeable Pavement Riparian Buffers Water Management and

Conservation

Wet PondsWet Ponds

InletsInlets

ForebayForebay

MicropoolMicropool

OutletOutlet

Aquatic Shelf Aquatic Shelf

Wet PondsWet Ponds

Stormwater WetlandsStormwater Wetlands

Stormwater WetlandsStormwater Wetlands

Stormwater WetlandsStormwater Wetlands

Bio-retention/Rain GardensBio-retention/Rain Gardens

InletInlet

Bio-retention/Rain GardensBio-retention/Rain Gardens

Permeable PavementsPermeable Pavements

Riparian BuffersRiparian BuffersRiparian BuffersRiparian Buffers

Water Management and Conservation

Water Management and Conservation

Pump StationPump Station

3,000 GallonCistern 3,000 GallonCistern

NestNest

Water Management and Conservation

Water Management and Conservation

NestNest

Water level indicatorWater level indicatorSpigotSpigot

SummarySummary Urban water cycleUrban water cycle

Less infiltration, more runoffLess infiltration, more runoff Stormwater transported pollutantsStormwater transported pollutants

Stormwater PollutantsStormwater Pollutants NutrientsNutrients SedimentSediment BacteriaBacteria WaterWater

Stormwater BMPsStormwater BMPs WetpondsWetponds WetlandsWetlands Bio-retention / Rain GardensBio-retention / Rain Gardens Permeable PavementsPermeable Pavements BuffersBuffers Water HarvestingWater Harvesting

AcknowledgementsAcknowledgements

Dr. Bill HuntDr. Bill Hunt Dr. Deanna OsmondDr. Deanna Osmond Dr. Greg JenningsDr. Greg Jennings Bill LordBill Lord Mitch WoodwardMitch Woodward Dwane JonesDwane Jones