I recently presented to CDWR’s Lunch-MAR group the findings for a series of studies we conducted on the universe of benefits from floodwater managed aquifer recharge (MAR) and the related economic and financing issues. I also proposed that an important next step is to run a set of pilots to study the acceptability of on-farm floodwater recharge projects to growers, including how do they respond to incentives and program design, and what are the potential physical consequences.

The key to initiating these pilots is getting a clear declaration from the State Water Resources Control Board that excess floodwaters are surplus and available. Unfortunately, the Water Board has not provided sufficient clarification on how these projects can take “advantage of seasonal or occasional flood waters that overtop the banks of a stream and are then directed into a designated recharge area.” Instead, the Board’s website says that such diverted floodwaters cannot be stored for future beneficial use–which obviates the very purpose of retaining the floodwaters in the first place.

The Board should be at least issuing temporary use permits for floodwaters above certain designated levels as being available for pilot projects on the basis that non-use of those floodwaters constitute a surrender of that right for the year. Then those agencies interested in flood MAR can design projects to experiment with potential configurations.