Daniel Cozad of the Central Valley Salinity Coalition: Addressing Salts and Nitrates in Central Valley Groundwater Irrigation Leader: Please give us an overview of CVSC’s activities. Daniel Cozad: We formed CVSC to work with the Central Valley Regional Water Quality Control Board and the California State Water Resources Control Board, which are state agencies, to rewrite regulations in a way that provides clean drinking water while ensuring the long-term sustainability of the region’s agriculture. That requires both a scientific and a technological approach. We also conduct legal and legislative efforts to set policy. In the long term, the biggest challenge for us is to build the salinity management infrastructure for the Central Valley. This effort is likely to cost billions of dollars over the next 25‑plus years. Irrigation Leader: Please introduce the issue of salt and nitrate concentrations in the Central Valley. A Central Valley orchard.
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armers in California’s Central Valley grow around 250 crops and provide one-quarter of the nation’s food. That intensive land use means a big thirst for water. But nitrates and rising salt levels threaten the clean water that communities and agriculture depend on. Irrigation Leader spoke with Daniel Cozad, the executive director of the Central Valley Salinity Coalition (CVSC) and the program director of the Central Valley Salinity Alternatives for Long-Term Sustainability (CV‑SALTS) program, about the coalition’s efforts to create a sustainable future for the region—and for the nation’s food supply. Irrigation Leader: Please tell us about your background and how you came to be in your current position.
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Irrigation Leader: How does CV-SALTS address that problem? Daniel Cozad: Nitrates are addressed within CV‑SALTS by groundwater subbasins called management zones. The management zones are organized as coalitions or nonprofit corporations. The board of each is made up of permittees in those areas. Farming and industry entities that need to be able to discharge nitrate generally join management zones for compliance in areas of high priority. As a group, they irrigationleadermagazine.com
PHOTOS COURTESY OF CVSC.
Daniel Cozad: I am a chemist by training, so water quality was my entrée into working in the broader water industry. I have managed a couple of regional public water agencies. In 2006, the Central Valley Regional Water Quality Control Board initiated the CV‑SALTS program as a cooperative effort among regulators, permittees, environmental interests, and other parties interested in Central Valley water quality. In 2008, I launched CVSC to supervise the study and business aspects of CV‑SALTS. CVSC is a nonprofit composed of about 25 members. About half of them represent either irrigated agriculture or related industries, such as food processing, wine, and dairy. The other half include cities, counties, special districts, and industry associations. I’m the executive director of CVSC.
Daniel Cozad: Nitrates from dairy and irrigated agriculture, septic wastewater treatment, and other sources already impair portions of the Central Valley’s groundwater used for drinking water and pose a potential health risk to a segment of the population. Rising salt levels threaten to turn this productive basin into a land where the water is not fit to drink and soils are not capable of growing highvalue crops. The water that moves through the Sacramento Delta into areas like the Tulare Lake basin and the San Joaquin Valley contains salt. With respect to irrigation, if you bring in irrigation water and not much of it leaves— in other words, if you’re farming efficiently—you’re going to increase the amount of salt through evapotranspiration. Previous agricultural practices were not as refined as today’s with regard to nitrates, and more nitrates were left in the root zone of crops and got into the groundwater below. If you use that groundwater for agriculture, there’s really no problem, but if you drink it, high concentrations can pose a problem.
