Recently, a family brought a drinking water sample to the health department laboratory after they had been ill for several months. Many medical tests had failed to find the cause.
The water test detected E. coli. This prompted them to look closely at their water system, where they found the well cap ajar, likely allowing contamination into the well. Since they properly attached their well cap and made other improvements, their health has been better and their follow-up water tests are good.
Drinking Water Week, which is May 3-9 this year, is a good time to think about where our drinking water comes from. Also, how do we make sure that water is safe and protected from contamination?
Here in Thurston County, our drinking water comes from groundwater fed by rain. In fact, about half our rain soaks into the ground and becomes groundwater. The soil does a pretty good job of filtering water as it makes its way underground, but some pollution on the ground can end up getting into the groundwater.
In addition, every well is a pathway from our surface activities to our precious groundwater supplies. For example, if your well seal is loose, mice may be able to enter and then fall to the bottom of the well, drown, and contaminate your water.
Everyone has a role to play to accomplish the Thurston Thrives goal of keeping water clean. We can all carefully manage items such as oil or yard and garden products that might leach into groundwater. If you have a private well, there are additional steps you can take to protect your water supply and make sure it is safe to drink.
Steps to protect your well water:
• Inspect your well casing. Cracks can lead to contaminants making their way into well water.
• Inspect the cap or cover on top of the well casing. There should be no openings, including around electric wires. The cap should have a gasket, making a watertight seal. If you try to wiggle the cap, it should not move. There should be a vent, screened with a fine mesh.
• Keep the top of your well at least 1 foot above the ground.
• Keep animals and their manure 100 feet away from your well.
• Keep household and yard chemicals, such as pesticides, fertilizers, auto products, paint, and other products with words such as “caution,” “warning,” “danger” or “poison,” away from your well. Do not store them in your pump house, or mix or use them within 100 feet of your well.
• Slope the ground away from your well. This will help rainwater that may contain surface contaminants (such as pesticides and oil) drain away and not pool around the well.
So how do you know if your water is safe to drink? Have it tested! If you receive water from a city or other utility, this is already done to assure a safe product is delivered to your faucet.
The health department recommends testing your water for bacteria every year and testing for nitrates every three years. We suggest testing sooner or immediately if you have a small infant at home or are trying to become pregnant. Water sample test kits can be picked up in several locations throughout the county; see the How to Collect a Water Sample web page at co.thurston.wa.us/health/ehdw/water_sample_instr.html or call the lab at 360-867-2631 for information.