Where Does Your Drinking Water Come From?

Only 3 percent of the water on earth is fresh water and suitable for human consumption. Two-thirds of the human body is water. We cannot survive more than a week without drinking. It should come as no surprise that people like to live near water, especially during the hot days of summer. In order to live near water supplies and continue to drink clean, safe water, it is important to know what to do to protect drinking water.

Protection begins with a few simple steps. The rule of thumb is: Don’t let anything into the drinking water supply that you wouldn’t want to drink. It is therefore important to know the origination of the water that comes out of your tap. At Lake Tahoe, tap water comes either from groundwater wells or from the lake itself.

All the water in the lake and in our aquifers comes from precipitation that falls within the Tahoe Basin watershed. Consider what paths water has to take to get to the lake or to your municipal well. In some cases, the water that comes out of your tap could once have been flowing down your street, as snowmelt or as runoff from your lawn. Or, it might have flowed across the parking lot at your workplace. Of course, all water supplied to your home by municipal systems is filtered, if necessary, and disinfected before it comes out of your tap. However, the more pollutants there are in drinking water, the more costly it is to make it clean and safe to drink. Plus, even municipal treatment systems cannot remove all types of chemical pollutants.

Lake Tahoe is an important source of drinking water. Compared to many sources of drinking water in the nation, Tahoe water is of excellent quality. When you visit the Nevada shores of Lake Tahoe, whether in homes, hotels, or restaurants, chances are you are drinking water from the lake, which has only been treated to kill the occasional bacteria. Water from Lake Tahoe supplies Reno and Sparks homes and businesses as well, via the Truckee River. What does this mean for you, as a resident or a visitor to Lake Tahoe?

When in the Tahoe Basin, consider the effect of your actions on the lake’s waters – the water you and others will be drinking. For example, when swimming at the lake and playing on the beaches, always use the restroom facilities provided – not the lake. Always pick up after your pets. (In one wetland area, over 600 pounds of pet waste was recently measured!) Practice safe and sanitary boating, keeping wastes and any fuel elements far from lake water.

Realize that the traces of pollutants left behind in the watershed result in costs that water consumers eventually have to pay. It is essential for all Tahoe residents, whether they live near the shore or not, to prevent erosion, overfertilization, overwatering, and overuse of pesticides. In addition, there are compounds in some household, industrial and automotive products that cannot be removed from water by municipal treatment. These products include household cleaners, used motor oil, paints and paint thinner, fuels, detergents, antifreeze, chemical solvents, degreasers, and brake fluid. Avoid dumping these products on the ground or into a storm drain, as they will eventually enter the drinking water supply.

Taking these steps to protect drinking water will also benefit our broad community effort to protect the world famous transparency of Lake Tahoe’s waters. The more we can protect the watershed’s soils and stream environment zones and restore natural watershed functions by using best management practices (BMPs), the cleaner our water will be. The old adage “an ounce of prevention is worth a pound of cure” truly applies to safe drinking water.

For more information, see “Watershed Management: A Multi-Barrier Treatment Scheme at Lake Tahoe” at http://www.epa.gov/OWOW/watershed/Proceed/standish.html or http://tahoe.ceres.ca.gov/stpud/districtinfo.html.


The Lake Tahoe Report 027

Air Date: 2003.08.05

Video Segment: Drinking Water & Your Health

Interviewees: Michelle Sweeney (NTCD)


Adopt-A-Watershed * Lake Tahoe Basin & Truckeee River Watershed * Revised 6/17/04