Matilija Dam debris problem

One of the reasons to tear down the Matilija Dam was to let all the silt and rock built up behind it to flow down the Ventura River and out to the ocean — where it would have gone naturally if not for the wall of concrete blocking the way.

But officials in charge of one of the largest dam removal projects in U.S. history have hit a roadblock. They no longer know where the 6 million cubic yards of silt and rock would go.

Of the two proposed disposal methods outlined in the plan to destroy the dam, one is proving too expensive and another was scuttled after private property owners said they didn’t want the silt on their land.

Darrell Buxton, a U.S. Army Corps of Engineers project manager in charge of the removal, declined to say what alternative options are being examined or how many there are. But he said they will find an answer that will keep the project on schedule to start deconstruction in 2011.

“I am confident that there will be a solution and this decision doesn’t have to happen until we are ready to take the dam down,” he said.

Critics say if another alternative is proposed —such as pumping all the silt to one location and making a de facto landfill out of it — much of the reasoning behind tearing the dam down will be lost.

“The objective of the project is quite clear in terms of ecosystem restoration, restoring the natural processes, restoring fish passage and the riparian habitat,” said Paul Jenkin, the head of the Matilija Coalition, which has been lobbying to have the dam removed for years. “Building permanent landfills is not restoring the natural process.”

Jenkin and others had thought the proposal was to put the silt into a series of pipes that would take it to strategic places along the Ventura River near Baldwin Road. It would then undergo a series of procedures to “dewater” it so it would become hardened. Over time, as big storms flooded the river, the silt would be carried downstream and out to the ocean. The rock and silt would help stabilize beaches in Ventura, including Surfers Point.

But Buxton said the dewatering process has become too expensive — the estimate has gone from $18 million to more than $40 million, he said.

Another alternative was to pump the silt down river to property owned by the Church of the Living Christ, where it would make an oblong sort of levee more than a half-mile long. But church officials said they didn’t want it on their land, which sent the engineers back to the drawing board.

“I wouldn’t say it’s a small issue, but it’s nothing we can’t work through,” said Peter Sheydayi, a director with the Ventura County Watershed Protection District, which is the lead county agency in charge of the dam removal. “With any project you end up learning things you didn’t expect and you have to work through them.”

Of bigger concern to Sheydayi is that if this part of the project is going over budget, he wonders what other costs will increase.

“Nobody expected the overall project to increase incrementally like we are looking for the Baldwin Road site,” he said.

Jenkin said when considering the total cost of the project — $140 million to remove the dam and build new infrastructure along the Ventura River — an increase shouldn’t stop officials from the proposal to pump it downstream.

“When we talk about permanent disposal and impacting recreation and other permanent impacts, that is a different deal than we signed on to,” he said.

Buxton said the new proposals of what to do with all that silt and rock should be made public by early fall and it shouldn’t slow down the timeline.