U.S. Army Corps of Engineers confirms non-navigable status for most of L.A. River

U.S. Army Corps of Engineers officials announced today that they are standing by their decision that most of the Los Angeles River is not navigable.

The ruling sparked sharp criticism from some other regulators and conservationists who warned that it will weaken federal Clean Water Act rules protecting the river’s sprawling 834-acre watershed.

They believe the ripple effect of the decision will make is easier to develop large areas of the Santa Susana, Santa Monica and San Gabriel mountains because landowners will not be required to obtain certain federal permits. Some federal and state officials fear that the decision also may undermine rules against discharging wastewater and storm water into the river’s tributaries.

Corps officials said that they will continue enforcing the Clean Water Act as usual along the river.

“This decision does not in any way lessen the protections on the L.A. River itself,” said Col. Thomas H. Magness IV, who oversees the Southwest regional office.

The Corps review of the largely concrete-lined urban river has been attracting national attention, since it is among the first to test the scope of a 2006 U.S. Supreme Court ruling that weakened protection of certain seasonal streams of the sort common in Southern California and the arid West.

Some landowners have questioned whether altering or building on those streams should require federal permits because the streambeds may only contain water a few weeks or months annually.

The 2006 ruling linked such Clean Water Act protections to the closeness of such streams to “traditional navigable waters.” The streams would have to have a direct effect on water quality in a navigable waterway to be protected, the ruling said.

The Corps made one change to its draft decision by adding as navigable the two miles of the Sepulveda Basin in the San Fernando Valley to the 1.75 miles of river between the ocean and the Pacific Coast Highway bridge in Long Beach. Adding the Sepulveda basin section of the river will extend protection to upstream tributaries, Corps official said, but they did not identify the specific streams.

Rep. Henry Waxman (D-Los Angeles) said in a statement: “I am disappointed with the Corps’ draft determination, and urge EPA to ensure the entire L.A. river basin remains protected by the Clean Water Act.”

 deborah.schoch@latimes.com