Re: allow now Tulare Lake to remain
Posted: Tue Apr 04, 2023 8:26 am
Groundwater recharge in the San Joaquin valley is what I worked on professionally. There are limits to the feasibility. The ground can absorb at limited rates, and a good share of farmland does not have great recharge rates. The big swings between drought and flood complicate picture too. There is the Corcoran Clay layer that limits most recharge to shallow groundwater. Just letting the flow sit in the center of the valley will not do a lot of good. Yes, you can perhaps make wetlands, but that would be primarily a wildlife benefit, which is not a bad idea in itself. But large area shallow water has huge evaporation losses that can result in saline water. Deep aquifer recharge mostly takes place up-valley closer to the Sierra. Each specific recharge area has its unique set of parameters; some work, others do not. There probably are better recharge sites east of Los Angeles in the desert. Problem is how to get the water there.
A big political and practical issue too. Water districts pay for construction and obviously store water for later use, which in recent years has included over-pumping and land subsidence, which destroys some of the aquifer's capability to hold water the next round. Economic feasibility is sketchy. It is very complicated and also comes with lots of unknowns. On a small scale there are some good recharge possibilities and current recharge projects have been built. But thinking restoring Tulare Lake will recharge the aquifer is not realistic.
A big political and practical issue too. Water districts pay for construction and obviously store water for later use, which in recent years has included over-pumping and land subsidence, which destroys some of the aquifer's capability to hold water the next round. Economic feasibility is sketchy. It is very complicated and also comes with lots of unknowns. On a small scale there are some good recharge possibilities and current recharge projects have been built. But thinking restoring Tulare Lake will recharge the aquifer is not realistic.