California Dairy Drip Irrigation

Central Valley, CA

PROJECT PARTNER: Sustainable Conservation
PROJECT TYPE: Agriculture Irrigation Modernization

California’s dairy industry is incredibly important for global milk production, as well as local revenue and jobs. Over 90% of the state’s dairies are located in the agriculturally-rich Central Valley, a region suffering from poor groundwater quality and increasingly uncertain water supplies.

Dairy producers in California use water to flush their cows’ stalls, and the nutrient-rich water is then applied to the crops producers grow to feed their cows through flood irrigation. While the practice is a good use of on-farm waste and reduces the need for synthetic fertilizers, many dairies often generate more manure and nutrients than can be applied safely to their crops. Excess nitrates and other potentially harmful substances can contaminate underground aquifers, threatening critical groundwater resources much of the Central Valley relies on for irrigation and drinking water. Dairies need a way to keep their water and nutrient use in balance to protect both water quality and quantity while maintaining the long-term viability of the industry in California.

In response to this challenge, Sustainable Conservation partnered with irrigation-technology firm Netafim USA to develop and test an innovative drip irrigation system that uses dairy manure through underground drip tape to deliver nutrients and water directly to the root zones of crops, where they need it the most, at the right rates. Many producers are already switching to drip irrigation in response to California’s challenging drought conditions, but current drip systems cannot filter dairy manure. Over two years of testing, the system is proven to reduce excess nutrients, apply the remaining nutrients to crop root zones for maximum uptake, and even improve crop yields. With the help of a significant Conservation Innovation Grant from the National Resources Conservation Service, we’re testing the system on three additional dairies that manage their manure and daily operations differently – by showing that the system works for a variety of management styles while saving and protecting water supplies, we can make a stronger case for industry-wide adoption.

For the California dairy industry, water scarcity and water quality are both serious risks. Consequently, there’s a clear business and environmental need to develop the technology needed to more precisely apply manure nutrients and to do so using less water. This will help the California dairy industry move from being seen as a major contributor to serious water problems in California’s Central Valley to demonstrating they’re actively contributing to the solution.