What Happens to Rainwater? Run-off Variability with Increased Impervious Surfaces (FISRWG, 1998) v 20 – 70% Impervious Surface 70– 100% Impervious Surface Natural Ground Cover 35% evapotranspiration 40% evapotranspiration 10% runoff 25% shallow infiltration 25% deep infiltration 38% evapotranspiration 21% shallow infiltration 21% deep infiltration 10 – 20% Impervious Surface 30% runoff 20% shallow infiltration 15% deep infiltration 55% runoff 10% shallow infiltration 5% deep infiltration 30% evapotranspiration 20% runoff
Water Quality Challenges Nutrients Sediment Bacteria “….While the main causes of degradation in the 1970s were point sources that could be targeted more directly, sources of contamination are now prevalent throughout entire watersheds and are caused in part by patterns of development, population growth, and consumer behavior….” Coming Together for Clean Water EPA’s Strategy to Protect America’s Waters, March 30, 2011
Nutrients in Rock Creek Nutrient Sources Stormwater Runoff ◦Rooftops ◦Driveways ◦Roadways ◦Yards Sewage ◦Treated and untreated Septic systems; a 24/7 source Pumping station overflows; an infrequent source Soluble Nitrogen Treatment plant with ENR (3mg/l) Septic System with Nitrogen Removal 10mg/l Old Septic System 20- 40mg/l NITROGEN IS THE ENEMY
Nutrients in Rock Creek Nutrient Sources Animal waste ◦Domestic ◦Wildlife Air Pollution 40% of the nitrogen inputs to the Bay are from atmospheric deposition
Sediment in Rock Creek Sediment Sources Erosion Poor vegetative cover Uncontrolled stormwater Poorly maintained erosion sediment control devices on construction sites
Bacteria in Rock Creek Bacteria Sources Illegal connections Leaking connections Failing septic systems Pet Waste Wildlife Raw sewage overflows 24/7 sources vs Weather related incidents
Restore Rock Creek Activities 2010 Non-Tidal Sampling 2010 Rainbarrel Demonstration and Sale 2011 Stream Clean Up 2011 Oyster Program On-going coordination with Anne Arundel County DPW On-going Research to Prioritize
What YOU can do to help Join Us Control your stormwater runoff ◦Check car, boat, motorcycle for leaks ◦Wash on lawn, not driveway ◦Recycle used oil ◦Use fertilizer/pesticides sparingly and according to directions AND soil test results ◦Plant deep rooted plants ◦Go native! ◦Sweep instead of hose ◦Vegetate bare spots ◦Replace waterfron lawn with native grasses ◦Eliminate impervious surfaces ◦Keep stormwater out of the roadways and stormwater systems – Spread the water out and slow it down!
What YOU can do to help Don’t overwater lawn, use drip irrigation Use nontoxic, biodegradable, recycled and recyclable products Clean paint brushes in sink, dispose of unwanted paint safely Disconnect downspouts Install a rainbarrel Install a rain garden PICK UP AFTER PETS Convert lawn to low maintenance landscaping Plant a tree!
What YOU can do to help… Drain spas/pools to sewer where possible Make sure no chlorine in discharge – Use Oxyclean Inspect and maintain septic system regularly