management, aquatic and land habi- tats and improvements to species and “ecological processes.” McCormack- Williamson was purchased by The Nature Conservancy in 1999 with the intent that DWR would restore it for fl ood management and environmental purposes. Winternitz said it holds “good potential” for Delta smelt because it is situated in “critical habitat.” “Restoring McCormack-William- son is restoring the habitat that these native species evolved in, so if we want to protect these species, McCormack- Williamson is a step in the right direc- tion,” he said.
McCormack-Williamson is one of the projects, along with Dutch Slough and Twitchell Island, that come under DWR’s Delta Levees Program, which aims to protect vital conduits in the Delta. “What needs to move next,” Minton said, are projects that make key levees in the Delta earthquake resilient, or as he put it, “shake, but don’t break.” “As part of this process, we learned about the importance of levees along the Middle River corridor, a key path- way for water delivered to the export pumps,” he said. “This pathway will be important whether or not these tunnels are built because on average, half of the water would still be diverted from the South Delta.”
Dutch Slough, a 1,200-acre wetland restoration project in east- ern Contra Costa County, offers the opportunity to be “a living laboratory where we could learn a lot about tidal restoration,” Newton said. Twitchell, a $4 million subsidence reversal/habitat enhancement project, is in the midst of construction that should be completed by Oct. 1.
Subsidence reversal has the added
benefi t of carbon sequestration, the process in which carbon dioxide is taken out of the air by plants such as tules and cattails. As the plants die and decompose, they create new peat soil, building the land surface over time. “There is net carbon sequestra- tion that happens,” Newton said. “In addition, because the Delta is subsided, you are also helping the island by
May/June 2013
reducing the hydraulic head against the levees on these deeply subsided islands. Granted, it will take 25 to 50 years, but it took us 150 to get them subsided. It’s a long-term project.”
In October 2012 the Coalition sent its list of 43 projects to Gov. Brown, calling them “good and worthy near- term projects that seem to get lost in the tensions surrounding these pro- cesses. Public water agencies say the Coalition can be benefi cial in promot- ing “a constructive dialogue among [its] diverse group of Delta interests.” The Coalition is not an indica- tion that Delta stakeholders are unifi ed in their desire to move the process in a particular direction, MWD’s Arakawa said. “We have made it pretty clear it doesn’t take the place of the broader need to solve the bigger issues of habitat restoration and the water delivery system in the Delta to meet the co-equal goals,” he said. “We want to make sure that somehow this doesn’t become a big political process; we want the BDCP to be completed, we want it to be put out to the public for comment, we want the state and federal agencies to take all of that and make a decision.” Several benefi ts coincide with using recycled water for irrigation and habitat restoration, including the recharging of aquifers currently used by
Clifton Court Forebay
“I think it gets lost on many people that this program is being developed within context of the Endangered Species Act; it’s breaking new ground for this area.”
– Stephen Arakawa, MWD
Listen to more of the interview with Stephen Arakawa
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