The water quality problem especially on Long Island in Suffolk County is reported to be acute- every water body within the county is listed as impaired with dead rivers, closed beaches, and harmful algae blooms. It is reported that Suffolk County has 360,000 septic systems. For years, nitrogen along with E. coli from leaky septic tanks has seeped into groundwater and eventually into rivers and bays. Water quality has continued to decline over the decades.
The county’s current strategy is to build two sewer systems in business districts on the North Shore in Suffolk County and “coax” homeowners to replace antiquated septic systems with high-tech “denitrification systems.” The challenge, however, is “coaxing” homeowners to replace their septic tanks. The problem with an old system is that unless septic is backing up into the house, most people don’t know their system is failing.
Nitrogen is more harmful to coastal ecosystems than to sources of drinking water. The federal standard for drinking water is 10 milligrams per liter, but anything above one milligram per liter will have an impact on coastal waters and estuaries. In Suffolk County, the average concentration of nitrogen in groundwater is four milligrams per liter, and with nitrogen, there is usually also E. coli.
Across the United States, tremendous improvements in water quality have been made in the decades after passage of the Clean Water Act in 1972. The biggest sources of chemical and biological pollution, the so called “point sources,” those releases from manufacturing and sewage treatment plants have been addressed. Sewage treatment plants have been build and improved, and waste streams regulated. The problem now is diverse and small sources of pollution that impact overall water quality and ecology.
Back home in Virginia, the EPA mandated a contamination limit called the TMDL (total maximum daily load for nutrient contamination and sediment) to Virginia and all the states in the Chesapeake Bay Watershed and Washington DC. Locally, the Chesapeake Bay TMDL addresses the contamination from nitrogen, phosphorus and sediments. However, there are other contaminants impacting the waterways of Prince William County- E. coli is among them.
Prince William county has been subject to TMDLs for bacteria impairments to: Cedar Run and Licking Run, Neabsco Creek, Popes Head, Broad Run, Kettle Run, South Run, Little Bull Run, Bull Run and the Occoquan River; and Tributaries to the Potomac River for years, but little has been done because the diverse sources of the problem.
The Department of Environmental Quality identified the primary sources of bacteria as follows:
- Cedar Run: livestock (65%), wildlife (26%) upland pervious land (9%), impervious (<1 li="" nbsp="">
- Neabsco Creek: wildlife (79%), pet sources (20%), livestock (1%)
- Broad Run: cattle – direct deposition (44%), residential, commercial, industrial (41.5%), wildlife – direct deposition (6.4%)
- Bull Run: cattle – direct deposition (56%), wildlife – direct deposition (30%), residential, commercial, industrial (13%)
- Occoquan River: residential, commercial, industrial (85.7%), wildlife – direct deposition (9.2%)
- Powells Creek: urban – developed land (87%)
- Quantico Creek: urban – developed land (94%) 1>
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