Increasing Protection for Drinking Water Sources

Approximately two thirds of our public drinking water supply in the U.S. comes from surface water and so protecting the source of those waters – the “source water” watershed – is an important strategy to ensure clean drinking water into the future. Algal blooms like the one in Lake Erie that threatened drinking water in Toledo, Ohio, and the chemical spill into the Elk River, upstream of the drinking water intake for Charleston, WV, underscore the vulnerabilities of drinking water supplies to pollution sources. This has led to legal action in some places, such as Iowa, where a drinking water utility has filed a lawsuit to ensure that upstream farms reduce nutrient runoff.

1996 Amendments to the Safe Drinking Water Act require that communities perform a source water assessment to delineate the watershed (or wellhead protection zone), conduct an inventory of potential contaminant sources and then assess vulnerabilities. From there, selected communities have taken different approaches to source water protection using land conservation, zoning, contaminant mitigation and emergency response planning to protect drinking water sources.

Finding funding or financing mechanisms to pay for source water protection is another important consideration for communities. In Raleigh, NC, the city has a watershed protection fee as part of the drinking water bill that funds watershed protection in Upper Neuse River watershed that drains to Falls Lake. In Santa Fe, NM, a watershed fee is part of a larger funding streams directed at reducing fire-induced sedimentation risk in the source water watershed on USFS land.

Finally, in some communities, like Georgia’s Flint River Basin, are starting to consider source water restoration by removing or retrofitting impervious surfaces to filter water and ensure baseflows.

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