Lawrence Berkeley National Laboratory and its founder and historical partner, University of California at Berkeley, are proposing a technological measuring device from outer space to solve the ethical problem of the distribution of water in California. Satellite images, analyzed by their computers, will achieve one primary purpose beyond whatever funding LBNL skims off the top: they will provide more bedazzling information to water lawyers.
And, in drought years groundwater makes up to 60-percent of the state's water supply.
Groundwater Issue: Supply | California State Water ...
https://www.waterboards.ca.gov/.../issue_supply.htmlJul 23, 2018 · During dry years, groundwater contributes up to 60 percent (or more) of the state's total supply, and serves as a critical buffer against the impacts of drought and climate change. Many municipal, agricultural, and disadvantaged communities rely on groundwater for up to 100 percent of their water supply needs regardless of whether it is a wet or dry year.
Procopiou, Lawrence Berkeley National Laboratory
Could the answer to groundwater resources come from high in the sky?
Groundwater makes up 30 to 50 percent of California's water supply, but until recently there were few restrictions placed on its retrieval. Then in 2014 California became the last Western state to require regulation of its groundwater. With deadlines starting this year, for the first time water managers in the nation's premier agricultural region—the state's Central Valley—are tasked with estimating available groundwater. It's a daunting technological challenge.
Now a new computational approach developed by scientists at the Department of Energy's Lawrence Berkeley National Laboratory (Berkeley Lab) offers a high-tech yet simple method: it pairs high-resolution images derived by satellite with advanced computer modeling to estimate aquifer volume change from observed ground deformation. The method could help streamline groundwater tracking across a region, once multiple local management agencies begin submitting water management plans to comply with the 2014 Sustainable Groundwater Management Act (or SGMA, pronounced "sigma).
"Drought has been prevalent throughout California's history and is inevitable in the future. The traditional methods for measuring groundwater levels have limitations for the type of integrated management required under SGMA," said Peter Nico, a Berkeley Lab environmental geochemist, and researcher involved in the effort. "Using this technique, it's possible to create a 'living' model of groundwater resources for the Central Valley that could be updated frequently and used at either a very local scale or a very large scale."
The method applies one of Berkeley Lab's key strengths—computing—to an area that is a significant point of focus for the Lab: water sustainability. The scientists believe it could lay the framework needed for water managers to portray Central Valley groundwater resources at a small, local scale and also at a broader scale that takes into account aggregated resources from various nearby jurisdictions.
What land deformation says about aquifer volume
In this project, the scientists leveraged data obtained from Synthetic Aperture Radar (SAR) satellites representing observed surface subsidence, or where land is sinking and groundwater storage capacity has shrunk. Such data provides a far more detailed and macro-level snapshot of aquifer compaction, a process that is sensitive to groundwater levels across the Central Valley. They paired the satellite observations with a public database of wells drilled in California in order to estimate the spatial distribution of the aquifer volume that is lost each month in the state due to pumping