Our Drinking Water is in Danger

The safety of drinking water is one of the most important public health issues in the United States or for that matter anywhere. During the 20th century efforts to achieve safe drinking water lead to developing drinking water quality regulations under the U.S. Environmental Protection Agency Safe Drinking Water Act (EPA SDWA). During that time providing safe drinking water focused on water filtration and treatment to kill bacteria. It was felt that simple reliable treatment could address any deterioration in source water quality.  Unfortunately, in our country where population is increasingly concentrated around crowded urban centers this may no longer be true.

Variations in water quality have undermined the ability of even advanced water treatment plants to control water quality and treatment and provide safe drinking water consistently and effectively. The rain and snow melt carrying pollutants from the air moves through the watersheds into streams and rivers and picks up additional contaminants along the way. As the water travels over the land surface or through the ground on its way to the rivers, it dissolves naturally occurring minerals and vegetation (organic matter) as part of the natural process. The water also picks up surface contaminants including  pesticides, herbicides and other synthetic/volatile organic chemicals from agricultural land, golf courses, or residential and urban lands.  Additionally, some previously unrecognized contaminants in trace amounts, pass through the treatment plant. There is a need for source water quality protection as an additional “barrier” to contamination and additional treatment may be necessary to deliver water free from chemical contamination.

Regionally, the Washington Suburban Sanitary Commission (WSSC), the Washington Aqueduct, Fairfax Water and Loudoun Water treat raw water obtained from the Potomac River, Patuxent River and Reservoirs and Occoquan Reservoir.  Potential sources of contamination in the region include transportation, petroleum pipelines, agriculture, onsite septic systems, wastewater treatment plant discharges, developed areas, and minor permitted discharges, storage tank leaks and spills. Contaminants of particular concern to the water companies include; phosphorus, agricultural runoff, natural organic matter and disinfection byproduct (DBP) precursors, pathogenic microorganisms (Cryptosporidium, Giardia, fecal coliform), taste and odor-causing compounds, ammonia, sediment/turbidity and algae.

Water drawn from the Occoquan Reservoir, the Potomac River, the Patuxent River Reservoirs is treated in the regional water treatment plants and is continuously tested for the contaminants regulated under the Safe Drinking Water Act before being sent to homes and businesses through the region. The first step is coagulation and flocculation (to make small particles and microorganisms in the raw source water adhere to each other); sedimentation (to remove most of those particles and microorganisms); filtration (to remove nearly all the remaining particles and microorganisms); disinfection (which varies across the treatment plants but kills bacteria and microbial pathogens); corrosion inhibitors/ pH adjustment (to minimize the potential for dissolving lead solder used in older homes and laterals lines); and fluoridation. Orthophosphate is also added to help minimize lead corrosion and copper pipe pinhole leaks in home plumbing by creating a protective film in pipes.

To ensure that tap water is safe to drink, EPA prescribes regulations, which limit the amount of certain contaminants in water that public water systems provide. The Safe Drinking Water Act regulates almost 90 substance, but that is a tiny fraction of the chemicals in use in a modern industrialized society. The quality of the water being produced at all our regional water treatment plants meets or exceeds all the US EPA standards and requirements. However, not all potential contaminants are regulated under the Safe Drinking Water Act.

Traces of pharmaceuticals, hormones and personal care products associated with everyday life in the United States are finding their way into groundwater and streams through septic systems and wastewater treatment plants and these micro pollutants can find their way into drinking water supplies. Drugs that people take are not all metabolized, and the excess ends up in our wastewater leaving homes and entering the sewage-treatment plants. These drugs have been detected in streams miles downstream from wastewater-treatment plants because most plants do not routinely remove pharmaceuticals from water. Antibiotics and drugs are also used in the livestock industry, and for streams receiving runoff from animal-feeding operations, pharmaceuticals such as acetaminophen, caffeine, cotinine, diphenhydramine, and carbamazepine, have been found in USGS studies.

Other problems are showing up as well, the Environmental Working Group (EWG) released the results of a new analysis, they commissioned of tap water samples from throughout the Northern Virginia region. The results detected some PFAS contamination in 19 samples of tap water ranged from about 6 parts per trillion, or ppt, in a state park in Fairfax County, to about 62 ppt in a public park in Prince William County. These levels though much higher than samples previously taken in Northern Virginia, are still below the U.S. Environmental Protection Agency’s (EPA) health advisory level of 70 ppt, that level is screening level, not a health based maximum contaminant level (MCL) for drinking water. The EPA has decided to move ahead and regulate PFOS and PFOA two of the group of chemicals called PFAS that are known as “forever chemicals” because they build up in our blood and organs, bioaccumulate, and do not break down in the environment.

Fairfax Water says “There are no treatment processes available for drinking water utilities that would not significantly increase water rates for customers. Nor would such treatments produce a demonstrated health benefit.”  Changing the water treatment chain at the Corbalis and Griffith water treatment plants would be necessary to treat the source water to remove PFAS. According to Fairfax Water this would "significantly" increase the cost of water for all the residents of Fairfax and Prince William Counties and unless there is a demonstrated health benefit they cannot justify the cost to the customers. So, they will wait for the EPA to develop a health based MCL. In the meantime we need to better protect the Occoquan Reservoir from chemical spills and accidental releases that are believed to have caused the PFAS contamination increase.

The Maryland Department of the Environment (MDE) has recently announced a settlement with Verso Corporation, owners of the Luke Paper Mill in Western Maryland, for seepages into the North Branch Potomac River. Samples of the substance being released to the river suggested the presence of ‘black liquor,’ possibly mixed with coal ash. Black liquor, a caustic mix of chemicals and wood waste from the paper-making process at the now closed plant, has a high pH, and contains hazardous constituents at concentrations that are harmful to aquatic life and humans. Coal ash contains a range of harmful constituents, including arsenic, mercury and boron, all of which were found in the Potomac Riverkeepers sampling. A petroleum odor was also noted by MDE. 

The former Luke Paper Mill is upstream of the intakes for all the regional water treatment plants and though well diluted by the Potomac can still enter our drinking water treatment plants. Protecting the Potomac River from chemical spills and releases is necessary to ensure that our dinking water remains safe. The time has come to limit the life of storage tanks, require removal are remediation of all closed manufacturing plants, and provide a natural barrier to pollution by limiting development in our essential watersheds. Development impacts water quality. Minimizing impervious surface cover and maintaining the tree canopy is critical to the protection of the region’s streams which flow to the Potomac River and Occoquan Reservoir. There is a direct correlation between stream health and impervious surface cover and tree canopy. According to the Northern Virginia Regional Commission, watersheds with impervious surface cover of 10 to 15% show clear signs of degradation, and when impervious surface cover is greater than 25% no longer can support a diverse stream ecology and are dying.