When It Rains, It Drains

1. When It Rains,It Drains An overview of Stormwater Management

2. Stormwater Runoff • Water falls as rain, snow, or ice • Most water seeps into the ground • If the ground is saturated, frozen, or has an impermeable surface, water flows as runoff

3. Point vs. Non-Point Source

4. Point vs. Non-Point Source • Point source: • Travels through a conveyance system • Regulated under permit program • Non-point source: • Runoff that comes from a wide unspecific area • Addressed through voluntary programs

5. Why is stormwater a problem? • Human activities cause stormwater to decrease in quality and increase in quantity • Caused by developed and disturbed land

6. Where does stormwater go? • Travels over land • Carried through Municipal Separate Storm Sewer Systems (MS4) • Discharges into various creeks and streams • Ultimately, the creeks and streams discharge into a larger body of water, like the Schuylkill River

7. Where does stormwater go? • Stormwater flows to storm drains along the street • Water may carry pollutants with it • This runoff goes to streams, rivers, lakes, and the oceans untreated

11. Southeastern PA Watersheds Conestoga DARBY CREEK WATERSHED

12. Stormwater Pollutants • Sediment • Oil and grease • Heat (thermal pollution) • Nutrients • Bacteria • Trace metals • Toxic chemicals

13. Sediment Pollution • Sediment comes from soil erosion and from decomposition of plants and animals • Sediment makes water cloudy • Sediment is the most common type of water pollutant

14. Sediment Pollution Prevention • Create vegetative buffers along bodies of water • Minimize the amount of exposed soil • Use silt fences when disturbing soil

15. Oil and Grease Pollution • The EPA estimates that 200 million gallons of oil are improperly disposed of each year • 1 quart of oil can contaminate 1 million gallons of water

16. Oil and Grease Pollution Prevention • Fix vehicles that are leaking fluid • If you change your own oil, store it in a container and dispose of properly

17. Septic System Pollution • The EPA estimates that 25% of homes in the U.S. use septic systems • Over 4 billions gallons of wastewater per day is dispersed below ground through septic systems

18. Septic System Pollution Prevention • Have septic system pumped regularly • Fix a faulty septic system • Fix faulty toilets and leaky faucets to reduce water going through the system • Don’t overload the septic system (ex: do several loads of laundry over several days, rather than all in one day)

19. Lawn Chemical Pollution • Lawn chemicals are fertilizers, herbicides, and insecticides • Over-application can cause toxic levels of chemicals and excessive nutrient runoff

20. Lawn Chemical Pollution Prevention • Conduct a soil test • Don’t over-fertilize • Use chemicals according to their instructions • Landscape with native plants

21. Thermal Pollution • Rain or snowmelt running over pavement picks up heat from asphalt and concrete • Warm runoff raises the temperature of bodies of water

22. Best Management Practices (BMPs)

23. Non-Structural BMPs • Pollution prevention and source control • Street sweeping • Stormwater collection system cleaning and maintenance • Low-impact development and land-use planning • Snow and snowmelt management • Public education

24. Structural BMPs • Green roofs • High density residential areas • Grassed/porous pavement

25. Hillside Elementary

26. Rain Gardens

27. Rain Impoundment Basin

28. Benefits of Stormwater Management • Enhanced opportunities for recreation • Reduced flood damage • Improved drinking water quality • Navigational benefits • Reduced illness • Enhanced aesthetic value