STUDY: Agricultural water use accounting provides path for surface water use solutions

Study: Agricultural water use accounting provides path for surface water use solutions:

Agricultural water demands can conflict with habitat needs in many North Coast watersheds. Understanding different water use patterns can help reduce conflict over limited supplies.

We measured on-farm crop water use and conducted grower interviews to estimate the agricultural water demand in the upper Russian River and Navarro River watersheds. Annual agricultural water demand was less than 11% in the Russian River, and 2% in Navarro River, of the total annual discharge in each watershed. However, because demands are concentrated in the dry season when instream flows are at a minimum, these relatively small amounts can represent a significant constraint to stream habitat conditions.

We have shared our study results in broad basin and community water resource planning efforts, including flow management of the Russian and Navarro rivers and implementation of the Sustainable Groundwater Management Act in the Ukiah Basin.

Findings and recommendations from this study have influenced on-the-ground solutions to meet water demand in these watersheds, including construction of off-stream wintertime storage capacity to replace summertime stream diversions, and use of a municipal recycled water conveyance system as a replacement for summer diversions.”

Read the study from California Agriculture here: Study: Agricultural water use accounting provides path for surface water use solutions


Stanford study offers a way to map where flooded fields best replenish groundwater

“In California, the amount of water exiting aquifers under the state’s most productive farming region far surpasses the amount of water trickling back in. That rampant overdraft has caused land across much of the region to sink like a squeezed out sponge, permanently depleting groundwater storage capacity and damaging infrastructure.

The trend – and a 2014 mandate for sustainable groundwater management in the state – has ignited interest in replenishing aquifers in California’s Central Valley through managed flooding of the ground above them. … ”

Read more from Stanford News here:  Stanford study offers a way to map where flooded fields best replenish groundwater

Tracking aquifer water with seismic noise

From Environmental Monitor:

“In drought-stressed areas like California where every drop in the aquifer counts, seismic noise may be the key to monitoring water. Harvard University PhD student and principal investigator Tim Clements spoke to EM about this recent work, and how it might be a game changer for water watchers across the country.

“The inspiration for this research was the historic drought in California from 2011 to 2017,” explains Clements. “This was the driest period in recorded history in the state. We started this research after California had implemented the first mandatory water restrictions in state history in 2015.” … “

Read more from Environmental Monitor here:  Tracking aquifer water with seismic noise

Streamflow availability ratings identify surface water sources for groundwater recharge in the Central Valley

From California Agriculture:

“In California’s semi-arid climate, replenishment of groundwater aquifers relies on precipitation and runoff during the winter season. However, climate projections suggest more frequent droughts and fewer years with above-normal precipitation, which may increase demand on groundwater resources and the need to recharge groundwater basins. Using historical daily streamflow data, we developed a spatial index and rating system of high-magnitude streamflow availability for groundwater recharge, STARR, in the Central Valley.

We found that watersheds with excellent and good availability of excess surface water are primarily in the Sacramento River Basin and northern San Joaquin Valley. STARR is available as a web tool and can guide water managers on where and when excess surface water is available and, with other web tools, help sustainable groundwater agencies develop plans to balance water demand and aquifer recharge. However, infrastructure is needed to transport the water, and also changes to the current legal restrictions on use of such water. … “

Continue reading from California Agriculture here:  Streamflow availability ratings identify surface water sources for groundwater recharge in the Central Valley

The Economic Impacts of Agricultural Groundwater Markets

From the Giannini Foundation of Agricultural Economics, University of California:

Groundwater markets offer a cost-effective means of meeting management goals under the 2014 Sustainable Groundwater Management Act. Using data from the Coachella Valley groundwater basin, we quantify the economic impacts of trade in one of California’s most important agricultural regions. Facilitating groundwater trade under a mandatory basin-wide “cap” on pumping will reduce disruptions to the local economy and keep land in production, relative to a scenario where trade is prohibited.

Specialty Crop Expansion in the Sacramento Valley- An Exploration of Groundwater Recharge Opportunities

From the Northern California Water Association Blog:

Sacramento Area Council of Government (SACOG)’s Sustainable Water Management Strategies for Specialty Crop Expansion in the Sacramento Valley examined scenarios to consider optimal locations for strategic flooding of cropland to maximize groundwater infiltration and improve water supply reliability for continued specialty crop production and related economic activities.

The work completed has identified attributes in our region’s open space land that facilitate infiltration and those that limit groundwater recharge potential. The project also examined ways these flooding scenarios may provide habitat benefits. The project included a contractual study component to complement RUCS staff work and build upon in-kind services from industry stakeholders, including specialty crop stakeholders, and water resource managers. The contractual work provided technical support and subject-area expertise in groundwater recharge science. This included the collection of environmental data to underpin scenario analysis and enhance the RUCS toolkit; including regional water balances and other factors that impact recharge (e.g. soil type permeability).

Click here to continue reading at the Northern California Water Association blog.