An excellent summary of the basics of groundwater from the California Water Blog.
Groundwater has been receiving a lot of attention lately, and for good reason. California is the heaviest groundwater user in the nation, and our use is increasing after recent, multiple dry years.
The Sustainable Groundwater Supply Act of 2014 set a fundamentally new state water policy to manage and monitor the state’s groundwater supply.
The effects will be far-reaching: groundwater accounts for about 40 percent of the state’s average annual water supply – about 16.5 million acre-feet, or roughly four full Lake Shastas every year. During drought years, groundwater can make up more than 65 percent of water supply. For more than 6 million urban users, groundwater is their only supply.
But improving groundwater management is complicated by misperceptions of how groundwater works and implementation challenges at state and local levels.
Against the backdrop of new groundwater legislation and ongoing drought conditions, the 2016 UC Davis California Water Policy Seminar Series will focus on groundwater, revisiting many of the issues covered during the Winter 2015 series. Nine presentations from policymakers, hydrologists, legal experts, economists and water managers discussed California’s management of groundwater – its past, present and future.
Groundwater – the basics
Tucked away beneath our feet, it’s hard to understand what we cannot see. Dr. Graham Fogg shined a light on the mysteries of groundwater. It doesn’t look the way we imagine it to look or necessarily work the way we think it does, Dr. Fogg cautioned.
“You see a lot of pictures where it’s all blue and there’s these little lenses,” he said. “People look at these enough and they get the idea that the system here in the Central Valley is really like that; it’s actually nothing like that.”
Take an in-depth look at aquifer systems with Dr. Graham Fogg: Groundwater Problems and Prospects, part 1: An overview of groundwater
Groundwater does not work in isolation – groundwater interacts with the surface waters above it and sometimes beyond. That connection was explored further with Maurice Hall, who helped draft the SGMA legislation in his previous position with The Nature Conservancy.
“If you have a lot of different wells, you can lower the water levels over miles and miles and miles of aquifer,” he said. “When you do that and the groundwater levels in the surrounding areas are lower than the stream, the stream loses water to groundwater.”