Dam removal study cost increases $1 million

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Rosi Dagit, a senior conservation biologist for the Resource Conservation District of the Santa Monica Mountains, and her colleagues conducted a study that confirms the historical presence of steelhead trout in Malibu Creek. Photo by Dave Lichten / TMT

Feasibility study for removal of Rindge Dam is yet to be released.

By Ben Marcus / Special to The Malibu Times

The draft feasibility study for the removal of Rindge Dam that was scheduled to be ready by June has yet to be released by the Army Corps of Engineers. The study, begun in 2002 and originally expected to cost $2.1 million, is now projected to cost $3.6 million.

Calls for the removal of the dam have been to help restore the native Southern steelhead trout to Malibu Creek, runs of which were estimated to be more than a thousand fish in the 1900s. However, there are detractors of the idea to remove the dam, which some, including the National Register of Historic Places, believe should be declared an historical structure.

In 1998, Congress appropriated funds for a reconnaissance study to determine whether the federal government had an interest in restoring the Malibu Creek watershed environment and protecting its associated shoreline, according to the official Web site for the Los Angeles District of the Army Corps of Engineers. The recon study determined there was interest and the Corps entered into an agreement with the California Department of Parks and Recreation in 2001 to share the costs of a feasibility study, which would look at ways to improve the Malibu Creek ecosystem and include assessing the pros and cons of taking down Rindge Dam, and removing the sediment, which would “open almost six miles of prime breeding habitat for the Southern California Steelhead.”

However, an estimated cost of $40 million to remove the dam and concern about potential flooding might be a roadblock to such an effort.

Rosi Dagit, a senior conservation biologist for the Resource Conservation District of the Santa Monica Mountains, confirmed the historical presence of the fish in Malibu Creek.

“Using the information we gathered that is reported in Dagit, Drill and Meyer, 2005, Historical Distribution of Southern Steelhead Trout in the Santa Monica Bay Region, it appears that there were consistently steelhead found in Malibu Creek since the late 1800s when first documentation was found. Numbers fluctuated over the years and are not exact, but we found records of ‘hundred’s’ of fish estimated as recently as the 1960s. In the early 1900s, the trout run in Malibu was front-page news in the L.A. Times, and, in 1916, before the dam went in, a 30-inch trout was caught in Cold Creek [a subwatershed of the Malibu Creek Watershed]. I think there is sufficient evidence to indicate that Malibu [Creek] has historically been an important steelhead stream.”

The dam builders

Frederick R. Rindge and his wife Rhoda May were early pioneers of Malibu and the largest landowners in the area in the late 1800s. Twenty years after Rindge died in 1905 at the age of 48, his widow began the construction of a large, “constant arch” dam three miles up Malibu Creek. Designed to provide a consistent supply of water from Malibu’s inconsistent, seasonal rainfall, the dam was framed with railroad ties, which created a two-level blockade that was 100 feet high and stored 574 acre feet of water.

The fortunes of the Rindge family began to decline shortly after construction of the dam as pressure by the state of California to put a highway through their Rancho Malibu property forced the family to fight several legal battles. Within 20 years of the construction of the dam, the Rancho Malibu was being sold and subdivided, and the Rindge Dam eventually almost completely silted over, and now stores sediment where it had once stored water.

The Rindge Dam was built with no consideration for the breeding habitat of steelhead trout, and since the construction of the dam, the population of steelhead in Malibu Creek has dwindled from hundreds to dozens, and sometimes to none. Limited to only the first three miles of Malibu Creek, the steelhead population began a slow decline, but was strong enough in the ’30s and ’40s to lure Clark Gable and Spencer Tracy away from movie sets to sample world-class fishing in the wilds of Los Angeles County. (An unexplained almost complete die-off the trout took place last year. The last count of steelhead in Malibu Creek was 32 as of last month.)

The dam was decommissioned in 1967 and became a part of Malibu Creek State Park, managed by the California State Department of Parks and Recreation.

An endangered species

Since that time, the Southern California steelhead was declared an endangered species in 1997. Anthony Spina, a biologist for the National Marine Fisheries Service, explained why the population dwindled to almost nothing: “Dams and other impediments to fish passage were identified as one of the principal factors leading to the decline of steelhead and ultimately the listing of the species as endangered under the U.S. Endangered Species Act. In this regard, one action that NMFS promotes, where reasonable and where necessary, to recover steelhead involves providing steelhead access to their historical spawning and rearing habitats where dams and other barriers preclude the species from such habitats.”

Spina went on to explain that steelhead migrate deep into extreme fringes of watersheds, including small tributaries, where environmental conditions favor reproduction.

“Dams that do not allow fish passage can cause reductions in fish abundance and loss of genetic diversity, both of which do not favor long-term survival of the affected species,” he said, adding that most dams in Southern California were not constructed in such a way to allow passage of adult steelhead to historical spawning and rearing habitat.

“One such dam is Rindge Dam on Malibu Creek,” Spina said.

Spina said removing Rindge Dam would almost certainly improve the steelhead habitat in Malibu Creek, noting the Army Corps of Engineers’ effort related to the removal of Matilija Dam [on the Ventura River], which he believes will be removed.

However, a descendant of the Rindge family has in the past called the idea of removing Rindge Dam a “folly” and has protested the idea of taking down what he calls a historical structure. Ronald L. Rindge has written in letters to The Malibu Times that he also believes the trout could not exist in the upper watershed of Malibu Creek because of high temperatures and poor water quality.

The National Register of Historic Places agrees with Rindge about the historical importance of the dam. A report, which was given to the Corps, recommended that the dam be formally listed with the NRHP. But biologists in the past have said that the creek is fine for the fish.

Dagit said, “There are definitely locations upstream suitable for steelhead, as we speak.”

The biologist also said that there are “refugia” sites upstream and below the dam that the trout use. Refugia are areas where seeps and springs put cold water into the creek.