Excessive nitrates ingested from the water supply are a serious public health threat. They can interfere with the ability of red blood cells to carry oxygen to the tissues of the body especially in infants and pregnant women. This threat exists at various times in more than 700 of California’s water supplies, primarily from fertilizer-related agriculture operations, but that is not the only source. There are three primary sources of nitrate contamination; agricultural/fertilizer operations, septic systems/waste, and natural erosion. Droughts do not cause nitrate contamination – the nitrates are either already in, and/or currently entering, the supply. The drought-reduced water levels in the aquifer can raise or lower the concentration depending on the where the nitrates are in the earth or water supply.
San Juan Bautista’s drinking water supply is off limits due to high nitrate levels, and the proposed solution, a treatment system, may not go online until the spring of 2015. However, this is not a new issue for the city. The same problems have existed for many decades; yet, there has appeared to be little public interest in dealing with it between water emergencies. In the fall of 2002, San Juan received a citation from the State of California Department of Health Services for failing to have an effective notification system from the laboratory that performed water quality testing. This allowed dangerously high nitrate levels in the drinking water to go unreported to the state and public as required by law.
In response to the citation, the city said it was developing a project to construct a surface water treatment system with a capacity exceeding a million gallons per day that was expected to be operating in 2005, but bureaucratic infighting doomed the project. It was a heavy price to pay for a disagreement.
The proposed treatment system will be expensive for the city and residents with limited financial resources, but to do the job right we also have to determine the level of nitrates in the water and ensure any currently active sources are under control. Total loading capacity of the water basin is under study by the San Benito County Water District with findings due in a year or so, and they will be important. The community has to hope any local emergency will be over by then, but the threat will remain.
There are good, logical reasons for identifying and controlling the sources of contamination. For one, trying to fix something without understanding the breadth or depth of the problem is a fool’s game. For another, although source control is a very long-term program, controlling active sources can be cheaper and more effective than only cleaning it up; you need both. If the sources of contamination are actively adding uncontrolled nitrates into the water supply, the engineers will be dealing with a significant unknown.
The lack of interest in the current issue by the anti-oil lobby speaks volumes. Here we have actual contamination, yet the crusaders are ignoring it because they can’t see a way to pin it on an oil company.
Regional contamination from many decades of agricultural operations has always been the real threat to our water supply and that will continue. Water problems are not political – we must address the real problems with real answers in both the short and long term.
