Central Pierce County, WA | Region 10 | US EPA

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Central Pierce County, WA

EPA Region 10 received a petition from the Tacoma-Pierce County Health Department on June 23, 1987, which requested EPA to designate the Clover/Chambers Creek Aquifer as a Sole Source Aquifer.

In reviewing the petition, EPA determined that the aquifer actually extends beyond this area and in 1989 proposed new boundaries consistent with national technical guidance.

The Central Pierce County Aquifer System consists primarily of unconsolidated sediments deposited by glaciers and associated meltwater. The ground water moves regionally toward the Puget Sound and river valleys that constitute the aquifer system boundaries.

Approximately 400,000 people live within the boundaries or in nearby areas which partly utilize ground water from the aquifer system.

Ground water from the aquifer system supplies about 60 percent of the drinking water used within the area. During peak demands, ground water supplies over 80 percent of the drinking water.

At present, the quality of drinking water supplied by the aquifer is generally good, but incidents of contamination are occurring with increasing frequency, and the trend is one of gradually decreasing water quality.

If water in the Sole Source Aquifer were to become unfit to drink, there are no feasible alternative sources of drinking water available.

You will need Adobe Acrobat Reader, available as a free download, to view some of the files on this page. See EPA's PDF page to learn more about PDF, and for a link to the free Acrobat Reader.

* Maps of individual SSAs are not available at this time. The map provided here includes all designated SSAs in Region 10


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URL: http://yosemite.epa.gov/r10/water.nsf/Sole+Source+Aquifers/Central+Pierce

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