on April 25, 2012
Article originally printed in The Sacramento Bee
by Matt Weiser
The U.S. Army Corps of Engineers will plant more than 30,000 trees on Sacramento River levees next winter, a move that would seem to contradict its own policy calling for levees across the state to be stripped of their trees.
The Army Corps in 2007 advised California levee managers that trees and shrubs threaten levee stability and must be removed. The order, which has been put on hold while negotiations continue, would eliminate millions of trees from hundreds of miles of levee in the Central Valley.
It was the first time the national maintenance standard had been imposed in California, which has long operated under separate rules that permit trees. Those trees now compose most of the remaining riparian habitat in the region, providing vital food and cover for wildlife.
In a little-noticed exemption, however, the Corps in October granted itself permission to plant more trees. Officially called a “variance,” the move applies to 83 sites, mostly along the Sacramento River, where the Corps performed emergency erosion repairs after storms in 2006.
Those repairs involved covering the eroded levees with giant hunks of rock, called riprap. Now the Corps will go back to those sites to plant willow trees and bushes to improve the habitat altered by the riprap.
The Sacramento District of the Corps sought the exemption from its headquarters in Washington, D.C. Claire Marie Turner, a project manager at the Sacramento district, called it evidence the policy can be flexible by allowing trees where they are needed for habitat and don’t harm levee safety.