If you thought California’s water wars were bitter, just wait until you see our water data wars.
Digital tools have expanded the ability of governments, companies and nonprofits to measure the uses of California water in detail, and thus build more water-efficient products, boost water conservation, and replace expensive and inefficient infrastructure.
But the abundance of water data effectively makes every piece of land and every drop of water in California the subject of measurement—and conflict.
The data also exposes the fragmentation and deficiencies of California’s system of water management.
The state’s new conservation requirements add to the stakes of arguments over data. As Californians struggled to save every drop during the recent five-year drought, the state for the first time imposed mandatory restrictions on water use—requiring that 400 local water agencies figure out how to reduce usage by 25 percent in 2015.
That shift, following 2009 legislation setting a goal of reducing urban per capita water use by 20 percent by 2020, is changing the way Californians fight over water—away from historic battles over dams, and toward new contests over maximizing the water we already have.
Among the questions to which new data is being applied: What incentives will convince most people to remove their grass lawns and, if they do, how much water do those removals save?
How much water do efficient toilets and appliances really conserve? Exactly how much water are we losing to leaks—and where can we make the most efficient investments to stop them?
Then there’s a bigger-picture quandary: can data help integrate our water use with our electricity and gas use—making ourselves so efficient that we effectively mitigate the effects of climate change?
That promising thought is mixed with real questions about the accuracy of the data we do have.
How precisely are we measuring evapotranspiration—the process by which water is transferred from the land to the atmosphere by evaporation from soil and by transpiration from plants? And how accurately are we measuring our land use to determine how much landscaping could be replaced by more water-efficient plantings?