Soil Erosion and Water Pollution

The relationship between water quality and soil erosion cannot be overemphasized. Soil erosion and residue management, especially surface water runoff, influence water quality. A silt fence, sometimes called a filter fence, is a temporary sediment control barrier used on construction sites to protect water quality in nearby waterways from sediment in stormwater runoff.

The problem with silt fences is that they only filter sand and silt, clay and nutrients flow through the fences.  Placing a berm of compost on the low side of silt fences adds the capacity to filter out clays and nutrients. Compost contains both positive and negative charges that attract both positively and negatively charged elements and clays.

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Maintaining Your Driveway Could be Hazardous to Your Health

Our roads, parking lots and driveways have taken a beating this winter and one of the signs (and smells) or spring is the seal coat which is used to protect the asphalt surfaces.  

Seal Coating is typically performed in the fall of spring given the fact driveway sealer is contains about 70% water by volume. Temperature and humidity work in tandem when it comes to drying and curing. High temperature and low humidity accelerate water evaporation; low temperature and high humidity take significantly longer to cure. The differences are staggering: a 20°F drop in temperature will double drying time while a 35°F drop will triple drying time.

While seal coatings contain a lot of water, coal tar-based sealcoat contains a lot of chemicals such as coal tar pitch which is known to cause cancer in humans and polycyclic aromatic hydrocarbons (PAHs) which are probable human carcinogens. 

PAHs also harm the aquatic food chain when the chemicals are washed into the watershed through stormwater runoff.  Studies have shown that PAHs are released from coal tar-based sealcoats into the air and homes, workplaces, and shopping centers, and also into ponds, lakes and streams.

Friction from vehicle tires grinds pavement sealcoat into small particles this dust is transported by wind, rain, and snowplows to nearby soil, and some is tracked into homes, where it becomes part of the house dust.  This dust is consumed incidentally when we put our hands or objects into our mouths.

For someone who spends their entire lifetime living adjacent to coal-tar-seal coated pavement, the average excess lifetime cancer risk is estimated to be 38 times higher than the urban background exposure. 

A team of Clemson University students performed tests on fish in urban Greenville and Easley streams and compared them to fish in non-urban Upstate streams. They found a much higher concentration of PAH toxins in the urban fish.  These toxins can cause tumors in some fish and may also cause heart defects.

Effective January 1, 2014 Minnesota has banned the use of coal tar-based sealcoats and even if your state does not have a ban in place, as a responsible citizen, be sure to specify coal tar-free products for your asphalt surfaces.  

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Capturing and Using Rainwater from Rooftops

Capturing Rainwater from Rooftops Can Alleviate Nation’s Water Woes

As America’s expanding urban areas struggle with major water supply shortages and runoff pollution problems, capturing rainwater from rooftops provides a tremendous untapped opportunity to increase water supply and improve water quality, according to a recent analysis on Capturing Rainwater from Rooftops by the Natural Resources Defense Council (NRDC).

By capturing hundreds of millions of gallons of rainfall, residents of these communities would obtain inexpensive onsite water supplies for non-potable uses, such as yard watering and toilet flushing, and would lower energy costs associated with treating and delivering drinkable-quality water.  It would also reduce the street litter such as styrofoam, plastic, and paper; yard waste such as grass clippings , tree trimmings, and leaves; and pet waste that gets washed into local waterways during the rainfall.

The NRDC report illustrates opportunities for capturing, treating and supplying harvested rainwater for non-potable purposes in Atlanta, Ga.; Austin, Texas; Chicago, Ill.; Denver, Colo.; Fort Myers, Fla.; Kansas City, Mo.; Madison, Wis.; and Washington, D.C. Several success stories also demonstrate the effectiveness of rooftop rainwater capture for new construction in New York, N.Y., and redeveloped buildings in Santa Monica, Calif.

The report comes as the U.S. Environmental Protection Agency is in the process of updating its national standards for controlling runoff pollution from new development and existing paved areas. NRDC encourages the agency to adopt national standards for on-site stormwater retention that will increase green infrastructure approaches such as rainwater harvesting. As a result, communities can effectively transform polluted runoff flowing to our waterways into captured rooftop rainwater used as an on-site water supply resource.