When we pump groundwater for any reason, whether it be for municipal use or irrigation, the groundwater supply will decrease. That is a given. And not only does that water disappear, the soil around it compacts, and subsides.
We have seen that happen in our Valley.
The only thing that can reverse that reality is for more water to be introduced from the surface — more water than is being pumped out.
“Surface water deliveries will become a critical part of providing adequate water to carry on our farming operations,” Robert Brewer, president of the San Joaquin River Association, wrote to his members in 2016.
Adequate surface water percolates into the underground water basin, which acts as a storage reservoir for municipal and agricultural use.
The state wants to regulate groundwater pumping in our Valley, but without adequate surface flows to provide recharge, the supplies will drop no matter how much they are regulated.
Water flowing in rivers and streams and in canals provides a source for percolation. The more water that flows, the more the underground supplies are balanced.
That is why the Temperance Flat Dam is so important to the future of life and farming in this Valley. Otherwise, there won’t be anything to regulate in dry years.
Someone has suggested that we build Temperance Flat Dam as a San Joaquin Valley public works project. That idea may seem overwhelming, but perhaps it would not be.
The early dams that were built along the Columbia River were built by irrigation districts and power companies, and the Northwest is still enjoying their many benefits.
There must be a way that we could do the same.