This week, March 9-15, is National Groundwater Awareness Week, a good time to appreciate the amazing resource beneath our feet.
Thanks to rain, snow and the force of gravity, our Earth accumulates groundwater, a precious underground resource that helps satisfy our requirements for fresh water. Groundwater originates from rain and melted snow, which trickle down through soils, sediment and bedrock into water-saturated subsurface zones known as aquifers. According to the Centers for Disease Control and Prevention (CDC), groundwater supplies roughly one-third of our freshwater, providing water to nearly 90 million people. In addition, another 13 million US homes access groundwater through private wells. According to the California Department of Conservation, the US uses some 80 billion gallons of groundwater per day for public supply, irrigation, livestock, manufacturing, mining, thermoelectric power and more.
Not surprisingly, groundwater can become contaminated with man-made and naturally occurring contaminants. For example, contaminants may enter groundwater by seeping into the subsurface from the ground level or by migrating into an aquifer from an underground source, such as a leaking septic system or gasoline storage tank. How do we protect our groundwater from contaminants?
The US Congress, in an effort to protect drinking water from biological, chemical and physical contaminants, passed the Safe Drinking Water Act (1974). In 2006, EPA issued the Groundwater Rule under the Act to further protect groundwater from disease-causing viruses and bacteria. The Groundwater Rule requires regular sanitary surveys of groundwater systems for the purpose of identifying and correcting deficiencies. But, you and I have an important role to play too, as we go about our daily lives.
Consumer Tips for Protecting Groundwater:1
- If you have a septic system, service it according to local health department recommendations.
Because of the sheer number of septic tanks in the US, they can be a formidable source of groundwater contaminants, including bacteria, nitrates, viruses, synthetic detergents, household chemicals, and chlorides, if not appropriately maintained, notes EPA. Never discharge hazardous substances into the household plumbing served by a septic tank system.
- Store, handle and dispose of hazardous substances2 properly.
Store hazardous household substances in secure, original containers. If necessary, mix these substances over level concrete or asphalt where spills can be cleaned up or absorbed. Do not dispose of hazardous household wastes by pouring on the ground, down the drain, toilet, gutter, sewer, abandoned well or into water bodies. Take hazardous household substances to an appropriate waste disposal facility or consider planning a one-day community collection program (EPA offers an online manual).
- Use plant foods, fertilizers, herbicides, and pesticides responsibly.
Overuse or inappropriate use of these substances can contaminate groundwater. University extension services offer free guidance on gardening responsibly. One example is the University of Maryland Extension Service’s Bay-Wise Program.
- Decommission abandoned wells on your property.
According to the Pennsylvania Department of Environmental Protection, proper well abandonment eliminates a pathway for migration of contamination, among other objectives. A qualified water well contractor can decommission abandoned wells safely.
Groundwater is our watery “buried treasure.” Help spread the word about protecting it!
Bruce Bernard, PhD, is President of SRA Consulting, Inc., Associate Editor of the International Journal of Toxicology and lives in the Neck District of Dorchester County, Maryland.
1These tips are based on information from the National Ground Water Association
2Hazardous household substances include paints, paint thinners, petroleum products, fertilizers, herbicides, insecticides and cleaning products.