Carson Valley wells show rising pollution

More than half the wells in Carson Valley show increasing amounts of nitrate and solid pollution.

Scientists at the U.S. Geological Survey say a newly completed study shows 56 percent of the 27 monitoring wells show rising nitrate concentrations. A third of the wells showed no change during the study, while 11 percent showed decreasing amounts of nitrate pollution.

Total dissolved solids also increased, according to the study, in 52 percent of those wells. None of the wells showed a decrease.

"The cause of these increases is likely to be related to the increase in septic tank usage over the past 40 years in the Carson Valley," according to the report.

USGS is the nation's largest agency dedicated to studying water, earth and biological sciences. It also performs mapping aided by more than 2,000 organizations to provide impartial scientific information to managers, planners and the general population.

The full six-page report on the Carson Valley is available from USGS.