Working Group Updates Irrigation and Land Management Group Recharge Group Big Projects Group Basin Management Plan ad hoc Committee

Irrigation and Land Management Group Jacqueline Vasquez John E. Eiskamp Sam Cooley

Project Title: Rotational Fallowing Background: Rotational fallowing can reduce water use by putting conservation into the land rental cycle. By allowing fields to fallow, it could save the 2.5AF on average applied to PV crops. Potential Yield: 750 – 1,250 AFY This assumes 2.5 AF/Ac are used on an average ranch and if there is an annual rotation of fallowed acres. Cost: $600,000 – $1,350,000 Costs assume $2,000 - $2700 / ac for ac Key Players & Responsibility: RAC, Borina Foundation, Landtrust, PVWMA? Implementation Timeline & Milestones: Phase 1: Funding for land rental secured. Phase 2: Rotation coordinated with landowners and growers. Phase 3: Land Fallowed. Implementation Issues: Expensive, potentially reduces crop yield. Potentially improves yield?

Project Title: Increased Irrigation Efficiency with Soil Tensiometers Background: Soil tensiometers can provide real time data on in situ soil characteristics and irrigation effectiveness. This alternative involves installation of soil tensiometers and a network of communication towers to provide data that would allow growers to manage irrigation needs with increased accuracy and reduce water use. Potential Yield: 1,000 to 2,000 AFY Estimated yield assumes 10 to 20% reduction of water use is associated with the system, that 50,000 AFY of water is used for agriculture, and that 20% of agriculture demand will use this new system. Cost: $48,000 - $50,000 Costs assume 5 base stations 15 repeater towers at $7100 and $3000 each. Growers rent probes at $150/ month Key Players & Responsibility: RCDSCC, Hortau, Landowners, Growers Implementation Timeline & Milestones: Phase 1: Locate tower locations and willing landowners (Fall 11) Phase 2: Establish towers (Spring 12) Phase 3: Growers rent probes (Spring 12 – Fall 12) Implementation Issues: Landowner agreements, full coverage, funding

Project Title: Education for Irrigation efficiency Background: Training in irrigation scheduling, the use of Evapotranspiration data and Distribution Uniformity for growers and irrigators is critical for optimizing irrigation efficiency. Driscoll’s, the RCDSCC, PVWMA can all play a role. Yield: Unknown If used in addition to all other projects implemented, will make additional gains in efficiency. Cost: $12,000 – $18,000 annually, Based on $3,000 estimated per training, with 3 to 6 trainings annually. Key Players & Responsibility: Driscoll’s, PVWMA, RCDSCC, MCRCD, Ag Water Quality Coalition Implementation Timeline & Milestones: Phase 1: Survey growers on irrigators’ needs Phase 2: 3-6 trainings / year held. Implementation Issues: Need for coordination among training partners

Recharge Group Katie Montano

Project Title: Managed Aquifer Recharge Background: By conducting a study of the basin and identifying sites with high percolation rates, a series of 2-3 catchment basins will be created to recharge the aquifer with surface and stormwater. Yield: 200 AFY – 600 AFY If the system were capable of delivering 8 AF/day of infiltration, then 30 days/year of system operation could put >200 AF of water into underlying aquifers. Capital Cost: (need cost) Key Players & Responsibility: RAC, Driscoll’s, Landowners, NRCS, RCD, UCSC, CSUMB Implementation Timeline & Milestones: Phase 1: Build Bokariza / Drobac basin structure and monitor Phase 2: Perc test 2 -3 other sites Phase 3: Implement basins at 2 – 3 other sites Implementation Issues: Water source available, and of reasonable high quality.

Current Potential AFY Yield Rotational Fallowing = 750 – 1,250 AFY Increased Irrigation Efficiency with Soil Tensiometers = 1, ,000 AFY Managed Aquifer Recharge = 200 – 600 AFY Education for Irrigation efficiency ??? Basin Target= 12,000 AFY Current Potential Yield AFY = 1,985 – 3,850 AFY 16% - 32%