New Flood Plan Could Save Threatened Oaks

Even as residents began circulating petitions to protest a flood control project that would destroy 140 oak trees, Thousand Oaks planners and county officials have worked out a compromise that may save more than half of the century-old oaks.

Planner Greg Smith said the county officials have come up with the plan to scale back the Lang Ranch retention basin, which is expected to be considered by the City Council on Tuesday.

“We’re thrilled that the flood control district has decided to be more sensitive to the habitat,” Smith said.

Under the compromise, 80 of the 140 threatened trees in an 11-acre barranca near Westlake Boulevard and Avenida de los Arboles could be saved.

A concrete spillway would be eliminated, as well as the road leading into the basin. In addition, flood control officials said they plan to contour around the trees, leaving as many intact as possible.

A 1986 federal court judgment settling a lawsuit brought by Lang Ranch developers forces the city to allow a 2,257-unit development, but that construction is contingent upon having a flood and debris basin to catch runoff from the hillsides.

Although Lang Creek is generally only a few inches deep, Erbes Road has occasionally been awash with water from the creek during major storms.

In first looking at the project, officials feared that the potential for downstream flooding would be exacerbated by the removal of vegetation that would have naturally absorbed storm water runoff.

But Smith said that flood-control officials have now concluded that drainage and landscaping throughout the development will control more runoff than they expected.

The proposed project would now be in two parts, with the flood-control basin going in the oak-lined barranca and the debris basin being constructed across the street.

Because debris will not accumulate in the water-retention basin, there will be less possibility of overflow, eliminating the need for a concrete spillway and saving a rocky outcropping on the hillside, Smith said.

“That makes a very significant improvement in the overall plan,” he said. “. . . Also, it would maintain the biological habitats.”

Residents who live nearby and use the Lang Creek area for recreation were dismayed to learn of the project last November. Not only were they up in arms about the loss of oak trees, but they said the animals that use the creek--including raccoons, owls, rabbits and even bobcats--would be displaced.

Bob Calverly, a member of a group called Save the Oaks, which formed in response to the Lang Ranch project and has been circulating petitions urging a compromise, said he was pleased to hear of the new alternative.

“That still wipes out 60 of them,” he said. “But 60 instead of 140 sounds like an improvement. I’ll be interested to see exactly what they are going to do.”

Mayor Jaime Zukowski said she wonders why it took so long for flood control officials to come up with the compromise. The environmental review process has been under way for several years.

“Studying all the alternatives is required in environmental impact reports,” she said. “Why this alternative wasn’t there until there was a public outcry raises questions.”