Nitrate contamination widespread on Central Coast farms

June 26, 2010

Thousands of farm owners up and down the Central Coast have wells that have been affected by nitrates due to heavy fertilizer use. [Mercury News]

Scientists believe that fertilizers are the leading cause of nitrate pollution in California groundwater. The Department of Water Resources reports high nitrate levels have forced more wells to shut down than any other contaminant.

Meanwhile, the Pacific Institute estimates that at least 1 million Californians have dangerous levels of nitrates in their domestic wells.

However, current regulations, or lack thereof, allow farmers to apply as much fertilizer as they need–and can afford.

As a result, experts say it is common for farmers to apply more nitrogen-based fertilizer than needed without any regulatory consequence.

Marchi’s Central farm, just outside Pescadero, failed to establish a protection zone to prevent excess fertilizer from entering the groundwater.  A shallow drinking well sits 30 feet away from rows of brussel sprouts and artichokes.

The problem is so common that Marchi’s Central Farm won’t be fined for having polluted the groundwater, even if it can be proven that the fertilizer is to blame, said Harvey Packard, supervising engineer with the Central Coast Regional Water Quality Board in San Luis Obispo.

The board is investigating Marchi’s Central Farm, while also trying to draft regulations that would limit the amount of fertilizer a farmer can apply in a field. Farmers would be required to develop a fertilizer “budget” to show they’re not using more than what the crop needs.

Other farmers might be required to install monitoring systems.

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The upper aquifer in Los Osos is just barely above the “limit” for nitrates, Santa Maria’s aquifer is way beyond that, the difference is Santa Maria has a sewer and Los Osos doesn’t.

Santa Maria is allowed to treat the water at the well head, Los Osos has to deliver the water pretty much as its pumped, they will not be allowed to use that water source (upper aquifer) until they build the highest per capita cost sewer in history.

The problem with the Water Boards is that they can set goals and specifications all over the place, They can designate special areas and require onerous remedies without scientific, or for that matter, ANY evidence at all.

Get ready farmers, Los Osos is laughing at you.

There are area’s in SLO that have posted sign’s about high nitrate levels in the water for over the last 12 years. The entire area off Tank Farm road to the east has contaminated water do to high nitrate contaminates.

How serious does this have to get? We don’t exactly have a whole lot of water to begin with. Here we go again, Government at it’s best. We have the best Agricultural University in the Country right here in SLO and we can’t figure out what to do about agricultural contaminants? Go figure?

Tank Farm runs East-West. What land are you referring to?

The waterboard goes after the farmers and individual homeowner but leaves oil companies and other politically connected off the hook. The farmers should start asking questions of the appropriate people and agencies about the way the waterboard interprets regulations for the farmers and local jurisdictions and then how they interpret regulations for oil companies and other large corporations.

The SLO Farm Bureau will probably do its best, but what can they do, when the process is backwards.

I think part of the problem with the CA and regional waterboards is that they do interpret laws for Large Corporations and for individuals and farmers in the same way.

But those are apples and oranges. And the little Oranges get squeezed.

Not that there isn’t Cronyism and other problems, such as favoring the hands that feed the politicians, but I think for this one, its mostly taking laws meant for corporations and applying them to individuals. (again)

Amazing to be reading this after all the time spent by the waterboard on other issues.

Nitrates are relatively easy to reduce by creating ponds prior to direct perculation. At 30 ft to a potable water well, I’d be more concerned with pesticides. Current regulations do not allow Septic tanks and leachfields closer than 300 ft to a well.

It is good that the waterboard is developing an awareness of the unintended consequences of over enforcement, and spotty enforcement.