For Immediate Release, March 25, 2014

Contact: Jeff Miller, (510) 499-9185,

 Army Corps Reverses Misguided Policy Requiring Clearing Trees From Levees

Corps Admits Vegetation Clearing Would Damage Endangered Species Habitats

SACRAMENTO, Calif.— The U.S. Army Corps of Engineers yesterday announced a reversal of its policy requiring removal of all trees and shrubs from levees to obtain federal money for disaster assistance. A new interim policy allowing levee vegetation applies nationwide and the Corps has promised a rulemaking to make it permanent. The vegetation removal policy was challenged by conservation groups and opposed by many local flood districts, since vegetation on many levees provides important habitat for endangered fish and wildlife, and its removal actually may reduce levee safety.

“The Corps is taking a step in the right direction with this interim policy to protect vegetation that endangered birds, fish and other wildlife depend on for healthy habitat,” said Jeff Miller with the Center for Biological Diversity. “This is a significant shift that will protect riparian habitat on levees not only in California but nationwide. We intend to hold the Corps to their promise of a final rulemaking that acknowledges the science showing trees do not threaten levee stability.”

The Corps will no longer disqualify levees with trees and other vegetation from receiving disaster relief funding. Corps vegetation standards implemented in 2009 allowed nothing but short grass on levees, which forced local flood control districts and levee agencies to choose between cutting trees from their levees, risking violations of other environmental laws versus losing federal money for disaster assistance in the event of a flood. Such a disqualification also risked higher insurance rates from the Federal Emergency Management Agency.

The Corps’ new interim policy states: “vegetation management will not be considered in making an eligibility determination. A final policy will be established through notice and comment rulemaking. Any eligibility criteria eliminated by this interim policy will be restored, if at all, only through a public rulemaking process.” Any vegetation rating the Corps produces for a levee will now be informational only.

The Center for Biological Diversity, Defenders of Wildlife and Friends of the River filed a lawsuit in 2011 challenging the Corps’ changes to vegetation standards, which contradicted Endangered Species Act requirements and failed to comply with environmental review standards under the National Environmental Policy Act. There is little scientific proof that trees actually threaten levee stability and the Corps’ own research shows trees can stabilize and strengthen levees.

After Hurricane Katrina, the Corps made major changes to its nationwide levee program, including new standards in 2009 banning vegetation on or within 15 feet of levees. The Corps required removal of trees and other vegetation from levees without any consideration of regional differences. Although many levees were designed to include streamside vegetation to enhance habitat, the Corps took steps to cancel all exceptions to the requirement all levees to be cleared without evaluating the impacts on endangered species or their habitats in California.

The Corps failed to prepare an Environmental Impact Statement prior to adopting the decision and did not consult with federal wildlife agencies under the Endangered Species Act for the impacts the agency concedes removal of vegetation would have on threatened and endangered species.

Removing streamside vegetation could harm endangered species such as chinook salmon, steelhead trout, green sturgeon, giant garter snake, least Bell’s vireo, riparian brush rabbit, southwestern willow flycatcher and Valley elderberry longhorn beetle. In many Southern California coastal streams, least vireos and flycatchers nest in riparian vegetation along levees; longhorn beetles inhabit elderberry trees on levees; and salmon and other protected fish swim in rivers along Central Valley levees. Riparian vegetation reduces sedimentation harmful to anadromous fish and provides shade that reduces water temperatures, which is critical for salmonids and other aquatic species.

Many flood control associations, flood control agencies and state resource agencies in California opposed the vegetation removal policy because compliance and subsequent environmental mitigation would be extremely costly, possibly enough to bankrupt some flood control districts, and would divert limited resources that could be better used to reduce risk factors for flooding. Removing trees could increase the risk of scouring, slope failures and other negative effects on levee integrity. The state Department of Water Resources (“DWR”) estimated the cost of compliance at $7.8 billion.

The California Department of Fish and Wildlife and DWR opposed implementation of the policy because it would “reduce public safety in California, result in extensive and unnecessary environmental damage, and remove the Corps’ responsibility to assist state and local maintaining agencies in ensuring the integrity of California’s levee system.” These agencies characterized the Corps approach as “attempting to address complex technical, financial, legal and institutional problems with a highly prescriptive, one-size-fits-all approach to vegetation management.”

The Center for Biological Diversity is national, nonprofit conservation organization with more than 675,000 members and online activists dedicated to the protection of endangered species and wild places.

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