The Center for Investigative Reporting and California Watch has a nice story out this weekend:
The water supply of more than two million Californians has been exposed to harmful levels of nitrates over the past 15 years – a time marked by lax regulatory efforts to contain the colorless and odorless contaminant, a California Watch investigation has found.
Nitrates are now the most common groundwater contaminant in California and across the country. A byproduct of nitrogen-based farm fertilizer, animal manure, wastewater treatment plants and leaky septic tanks, nitrates leach into the ground and can be expensive to extract.
The problem affects both rural Californians and wealthier big-city water systems. State law requires public water systems to remove nitrates. Many rural communities, however, don’t have access to the type of treatment systems available in metropolitan areas.
Nitrates have been linked to “blue baby syndrome,” which cuts off an infant’s oxygen supply. Some studies have found connections to certain cancers in lab animals.
The State Water Resources Control Board acknowledges that nitrates are a problem affecting vast regions of California. And the situation is worsening, especially in the Central Valley, Central Coast, and the Los Angeles and Imperial Valley regions. High nitrate levels have already impacted public water system wells in many areas, and the contaminants continue to migrate toward groundwater supplies that could ultimately impact the water supply for millions of additional Californians.
Statewide, the number of wells that exceeded the health limit for nitrates jumped from nine in 1980 to 648 in 2007. Scientists anticipate a growing wave of nitrate problems in some parts of the state if remedial steps aren’t taken.