Government scientists and researchers at UC Davis will test a novel way to capture a gas associated with global warming before it gets into the air, and possibly help shore up levees in the Sacramento-San Joaquin Delta.
The California Department of Water Resources on Wednesday said it has awarded $12.3 million to a project that aims to discover whether carbon dioxide can be stored in marsh plants and soils while also restoring Delta islands and, in the process, protecting levees.
Delta islands consist mostly of organic peat soils, which evaporate when exposed to the atmosphere via farming and development. As a result, many islands have become bowls, with interiors more than 20 feet below sea level.
This can weaken surrounding levees, creating what scientists said is at least a 20 percent chance that multiple islands will flood in an earthquake within the next 25 years.
The U.S. Geological Survey proved in a 14-acre pilot project on Twitchell Island that growing native tules in carefully controlled conditions increased soil depth as much as 10 inches from 1997 to 2005.
The new project will expand the USGS test to 400 acres on Twitchell Island, and UC Davis will help gather data on how much carbon dioxide is captured in the process.
Carbon could be stored in the new peat soil that results from allowing tules to live and die naturally.
If successful, the sale of carbon credits to grow tules could fund a new kind of farming in the Delta while improving habitat and flood control. Those conditions could help officials avoid having to spend billions of dollars on taller and wider levees.
"It could provide sustainable farming opportunities for Delta farmers and an economic incentive to sustain the existing Delta levee system," said Dave Mraz, chief of Water Resources' Delta-Suisun Marsh Office.
Construction of the new project is scheduled for next spring.
Carbon capture is among the maneuvers being examined by researchers as one way of cutting the amount of global warming gases in the atmosphere.
For example, the California Energy Commission is leading a group of state government and private researchers in a test that will pump carbon into the porous sediment deep under the soil near Thornton, on the edge of the Delta.
Call The Bee's Matt Weiser, (916) 321-1264.
