Since Jan, 2014, 976 Tulare County CA Water Wells Have Failed - Dry Or Contaminated
A significant number of wells that are going bad is qualifying Tulare County residents at a rate of two bottles of water a day to help, according to county health officials. For the week ending March 25, there have been 976 Tulare County wells go dry since January 2014 — 14 additional wells from the prior week. That's scary news for users relying on well water, which is roughly four in 10 Tulare County residents.
As the water table drops, not only is there less water but the water that's left becomes more contaminated with unhealthy compounds. Many wells in the San Joaquin Valley have tested positive for contaminants such as nitrates, arsenic and bacteria, according to Visalia-based Community Water Center.
Continuous drought conditions is forcing more groundwater pumping, causing water tables to sink and water pumps to lose pressure and suck in contaminants. Nitrates can cause a potentially lethal condition in newborns called "Blue Baby Syndrome." As the name implies, nitrate interferes with the ability of blood cells to carry oxygen. Arsenic is a known cancer-causing element.
When groundwater diminishes, contaminants also become a problem because they occur in higher concentrations. For example, if you put a teaspoon of nitrate into a cup of water, it will register a certain concentration. If you put the same amount in a half-cup of water, the concentration will double. By far the most affected area, and most documented, is in the Porterville area, particularly East Porterville where roughly 600 of the 976 well failures have occurred, said Andrew Lockman, manager of the Office of Emergency Services for Tulare County. The water table there is shallow and it drops very quickly under drought conditions.
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http://www.visaliatimesdelta.com/story/news/local/drought/2015/04/13/tulare-county-wells-failing-california-drought/25723419/