Ground Water Atlas of the United States -
Segment 1 California Nevada
Ground-Water Quality
The quality of ground water in the Eureka area is generally acceptable for most
uses, although concentrations of dissolved iron in water from many wells may
exceed the U.S. Environmental Protection Agency's secondary drinking-water
recommendation of 300 micrograms per liter. Chloride concentrations in excess of
the 250 milligrams per liter drinking-water recommendation are reported in water
from wells near the Eel River as much as 4 miles inland from the Pacific Ocean,
suggesting that the source of the chloride is brackish water from the tidal
reaches of the river. Shallow wells in the dune sands also are prone to seawater
intrusion because they must obtain freshwater from a thin lens that floats on
saltwater. Excessive withdrawals or minimal recharge lower the freshwater head
in the dunes and allow salty water to be drawn into wells.
Back to "Fresh Ground-Water Withdrawls" - Forward
to "NORTH SAN FRANCISCO BAY AREA VALLEYS"
Back to Coastal Basins aquifers "Contents"
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