Water for the future: Supporting California farmers to replenish groundwater for drought, flood and climate resilience
Please briefly describe your Water ChangeMaker journey
Like many of the world’s agricultural hot spots, California’s farming regions experience severe groundwater overdraft due to decades of unregulated pumping. In the San Joaquin Valley, which accounts for more than half of the state’s food production, aquifers are losing 587 billion gallons (1.8 M acre-feet) of water per year. Overdraft at this scale causes drinking water and irrigation wells to go dry, harms ecosystems, and reduces resilience to future droughts. Facing persistent groundwater depletion, more frequent and intense droughts, and storm events, and outdated grey infrastructure, California needs new approaches to managing its water. Partnering with farmers, water districts, industry groups, researchers, NGOs, and government agencies, Sustainable Conservation is leading an innovative strategy that integrates flood management with groundwater management to capture high flows from storms and store them underground. This solution mimics California’s historical water cycle -- when snowmelt and rain would flow down from the mountains and across the floodplains to recharge the aquifers -- but in a managed way so that excess water is purposefully delivered to suitable farmland for groundwater infiltration. This integrated water management solution is an essential climate resilience strategy for reducing flood risks to downstream areas, recharging groundwater, and improving ecosystem conditions.
Please describe the change that your initiative created and how was it achieved
By demonstrating that excess surface water can be used to flood active farmland to refill aquifers without damaging crops, we are changing the way California manages its water. We have identified six stages on this journey: 1)Pilot (2011) – participated in a project in Fresno County with a farmer who had been experimenting with accepting floodwater onto his lands for 30+ years to help evaluate and document the capture, diversion, and recharge of 3,000-acre feet of floodwater on 1,000 acres of farmland. 2) Potential to scale (2012) – evaluated the pilot and other studies to determine that farm recharge could address between 20% - 33% of the overdraft in basins in the San Joaquin Valley. 3) Barriers to scaling (2013 -) - To address skepticism from the farming community, we interviewed growers, identified the needed information and guidance for on-farm recharge, partnered with researchers, and developed decision-support software. 4) Driver of Change (2014) - Interest in groundwater recharge grew following California’s passing of the Sustainable Groundwater Management Act (SGMA) that requires all priority groundwater basins be in balance by 2040 with key milestones. 5) Stakeholder collaboration (2017 -) To expand OFR, we have collaborated with farmers, water agencies, scientists and agriculture associations. We were invited by the California Department of Water Resources to co-coordinate an initiative (FloodMAR) aiming to fully integrate flood and groundwater management. 6) State policy (2015 -) worked with the CA Water Board to support obtaining the right to divert flood flows for groundwater recharge.
How did your initiative help build resilience to climate change?
California’s current water management problems will be exacerbated by the increased volatility in the drought-flood cycle that is expected with continuing climate change. The recent drought (2012-2016) left towns without safe and clean drinking water, aggravated groundwater overdraft, accelerated land subsidence, and damaged ecosystem conditions. Immediately following this, in 2017, the state experienced historical storms that led to more than 100 incidents of flooding, with much of the excess water being diverted out to sea. The failure to capture more of this water and divert it over suitable farmland for aquifer recharge represents a lost opportunity. Groundwater is an increasingly essential climate change adaptation strategy for California. Our initiative works at the farm level, water agency level, and policy level to ensure that these decision-makers can work together to anticipate high water events and divert stream flows to agricultural lands for recharge to build resilience for low water periods.
What water-related decisions did your initiative influence or improve?
Sustainable Conservation works with a number of water districts in the San Joaquin Valley to help them plan and implement groundwater recharge programs. In 2019, we supported Madera Irrigation District (MID) to distribute available floodwater to growers for recharge during the winter (February - April) and fall (October) “water seasons.” This included implementing grower outreach workshops to recruit farmers and support decisions around crop suitability, timing and volume of recharge, using our Groundwater Recharge Assessment Tool with water managers to identify and rank suitable land, crop and soil type, and presenting data to MID on the results of their two recharge programs to inform future decision making. As a result, 377 growers participated and 10,700 acre-feet of water were recharged into the aquifer. This was a significant increase over 2017 recharge (107 growers and 4,000 acre-feet of water recharge) that built resilience for groundwater use in future dry seasons.
What were some of the challenges faced and how were they overcome?
At the local level, farmers have been skeptical of flooding active cropland due to possible agronomic impacts. To address these, we have conducted grower outreach workshops where we partner with farmers and ag organizations (e.g. Almond Board of California) with experience doing recharge and facilitate demonstrations and discussions. We are also continuously collecting data on recharge and interviewing farmers so that we can provide practitioners with informed guidance and information, including a Crop Compatibility Calendar that advises the best crops and seasons for recharge. For water/irrigation agencies, we’ve experienced some pushback around the decentralized nature of integrated water management; managing flood flows for recharge requires relying on other water managers further upstream as well as farmers for offtake, and we addressed this by helping districts recruit farmers and plan detailed recharge programs. Another challenge has been the considerations around impacts to water quality; for certain agricultural lands, implementing groundwater recharge may push residual chemicals into the aquifer and degrade water quality. We have addressed this concern by working with local communities, farmers and scientists in the San Joaquin Valley to gather best practices and science to develop guidance that allows for the recharge that is protective of water quality.
In your view: Will the change that was created by your initiative continue?
We have been working on this integrated water management strategy for nine years, and it has received considerable traction among stakeholders. We are now partnering with five water agencies in the San Joaquin Valley to support planning and implementation and post-event analysis of their on-farm recharge programs. Additionally, we know from our partnerships with the California Department of Water Resources that integrated flood and managed aquifer recharge will be an integral component in the state’s overall climate resilience portfolio. Finally, California’s Sustainable Groundwater Management Act (SGMA) has established regulatory pressure for decentralized water management across the state, requiring local agencies to establish and implement ‘groundwater sustainability plans’ for the overdrafted basins so that they only pump as much water as they can replenish. The use of floodwaters to restore groundwater supplies will be a key strategy, and Sustainable Conservation will continue to work to expand knowledge and practice of this solution.
What did you learn during the initiative or after? And is it possible that others could learn from you?
One of our biggest learnings has been around the importance of strategic coordination in this initiative. Successful implementation of a ‘climate solution’ such as this one requires a strategic approach that is neither bottom-up or top-down but multi-tiered. When we and our partners have succeeded, it's been when we’ve done our part to make sure that all stakeholders are working from the same common understanding. To identify and successfully scale this solution we had to engage practitioners in the field (farmers, water managers), scientists (agronomists, economists), private sector groups (Almond Board of California, food companies), NGOs and government (Department of Water Resources, State Water Board). For example, decisions on whether to flood crops have the potential for considerable agronomic impacts, and so we engaged farmers and agriculture associations and sought the right scientists to do the research that would address concerns and improve grower confidence.