Connecting Soil Health and Water in California
Healthy soil practices are an essential strategy for making the best use of rainfall and stewarding irrigation inputs wisely.
California farmers are often concerned with water, what it costs, and its short supply. With recent droughts — made more intense by climate change — farmers have relied more on groundwater as surface water allocations decline. More reliance on groundwater has caused rapid depletion in many regions and prompted state regulators to make groundwater use more sustainable. California farmers face tough choices about how to adapt to a future with less water.
In a new BFI Policy Brief, we introduce healthy soil practices as an essential strategy for making the best use of rainfall and stewarding irrigation inputs wisely. Cover cropping, planting hedgerows, and reducing tillage create healthier soils, which then provide on-farm water benefits. Healthier soils can also support beneficial plant-microbe interactions and allow roots to grow more widely and deeply — allowing crops to better deal with water stress while maintaining productivity.
All of these aspects of soil health are crucial to helping growers become more resilient in the face of intensifying climate change and a stressed water supply.
This BFI brief is based on interviews by researchers at the Center for Diversified Farming Systems with 45 nut and leafy greens farmers in the Central Coast and the Central Valley between 2019 and 2021, as well as a 2018 California statewide survey with 140 agricultural extension personnel. This research led to the following recommendations to state policymakers:
- Provide California Department of Food and Agriculture (CDFA) funding for long term trials that study the impact of using soil health building practices on water. In addition, the University of California should provide a stable, funded infrastructure for research and monitoring of connections between soil health and water resources in California, including long term field trials.
- Evaluate how the CDFA’s Healthy Soils Program (HSP) has supported growers to adopt and continue healthy soils practices, especially with regard to water benefits, with the aim of using this data to guide further scaling up of these practices statewide.
- Create stronger synergy between the HSP and the Sustainable Groundwater Management Act (SGMA) to ensure that soil health and groundwater management are prioritized together.
- Create stronger synergy between the HSP and the Irrigated Lands Regulatory Program (ILRP) to ensure that soil health and water quality are prioritized together.