When the Los Angeles County Department of Public Works (DPW) proposed work at Santa Anita Dam its purpose was clear: the dam would need work to bring it into compliance with State seismic regulations and the build-up of sediment would have to be removed to free the flow of water and to provide additional storage to supply the water needs of the area.

Ultimately, a 350 page Final Environmental Impact Report was issued and received approval to proceed from all federal, state and local agencies in 2009.  The EIR squarely places the issue to residents of Monrovia, Arcadia and Sierra Madre whether dam safety and additional water storage should trump the saving of oaks that the plan would remove—but later replace—to provide a dumping spot for the removed sediment.

The dam's difficulties stem from the decomposed granite, the basic soil of our local mountains that, during rain storms, brings sediment and debris sluicing into the dam leaving a base of muck that needs to be removed about every 10 years. That sediment is now 33 feet deep and already hinders the valve operation, two things that have concerned the State agency for dam safety.

To prevent collapse of the dam as a result of a major earthquake, the California Dept. of Water Resources, Division of Safety of Dams, is demanding less water be kept in storage to keep pressure against the arch-dam front at bay and provide release valves to control the amount of water flowing into the dam during storms.

The report says that if the dam were to burst, flooding of areas around the wash and nearby low-lying areas would be expected and some 4,800 acres below the dam would flood an area that would extend south of the Foothill Freeway, including a large residential area, several schools and churches and parks leaving extensive property damage and a potential for the loss of life.

Flood control has been an issue in the Los Angeles basin for decades. Eighty-four years ago, Los Angeles County recognized the need for flood and debris control and began to build a series of dams, including the Santa Anita Dam, to not only control the run off to the lower areas but also to manage the sediment and debris carried down and to provide safety to residents living within the path of the dam.

These issues prompted The Los Angeles County Department of Public Works, now the agency controlling Santa Anita Dam, in 2007 to introduce a plan to clear the reservoir of sediment, improve the functionality of valves that control the flow of water, and be able to store a larger amount of water behind the dam.  The plan is officially dubbed the Santa Anita Dam Riser Modification and Reservoir Sediment Removal Project.

The project as currently envisioned would entail draining the Santa Anita Reservoir and removing sediment and debris using a 1½ mile long conveyor belt passing through a tunnel, over Wilderness Park parking lot, dropping the anticipated 500,000 cubic yards of dirt removed in a to be developed 13-acre site and also in an existing sediment placement site on the east side of the Santa Anita Wash, approximately behind Highland Oaks Elementary.

While the Upper and the Lower sites have been used in previous sediment removal plans, only the Middle SPS represents a new site for the removed silt. The Middle SPS has been mostly undisturbed over time and contains a combination of native vegetation, mature oak and sycamore trees and shrubs.   

A formal oak tree survey of the Middle SPS was conducted in 2007 by a certified arborist and two biologists. Their site survey listed 179 oak trees—177 coast live oaks, one is scrub oak and one Engelmann oak.

The City of Arcadia Municipal Code provides protection for Engelmann oaks and coast live oaks and lists specific trunk diameter measurements for trees which cannot be removed without permit. However, the city sent a letter to the LACDPW in 2008 stating that an Oak Tree Removal permit was unnecessary for public projects therefore the proposed project would not be subject to the City of Arcadia's Oak Tree Preservation Ordinance.

The project is expected to last over a two-year period and each year will entail six to eight months of construction activity. The largest traffic impact, the report says, is expected to be at Highland Oaks Dr., north of Elkins as some 43 workers enter and leave work and a few trucks access or leave the area.  Other areas that might see a small increase in traffic are Elkins Avenue between Wilson Avenue and White Oak Drive; Santa Anita Avenue south of Elkins; Santa Anita Avenue south of Andrea Lane; and Santa Anita Avenue south of Sierra Madre Boulevard.

Jason Kruckeberg, Development Services Director for the City of Arcadia, questioned many of the proposal details in a letter dated June 16, 2008.

In his letter, he concedes the need for improved water volume at the dam and seismic safety, but worried about visitor safety at Wilderness Park  in and around (or under) the conveyor system; visual landscaping protections in the sediment placement areas; dust control; mitigation measures and re-establishment of Live Oaks; noise; and other particulars.

In its response, the County assured Kruckeberg that safety netting would be employed around any conveyor belt area accessible by the public, that the county would use noise barriers, and responded to Kruckeberg's concern for the oaks saying that the project would require replacement of vegetation and, specifically, oaks.  The county response, though, says the funding of the replanting of oak trees would be left to officials of the City of Arcadia and the California Dept. of Fish and Game an accomplishment that seems at odds with Arcadia's statement earlier that it has no control over a public project and would take no action to preserve oaks through its ordinance.   

The Santa Anita Dam, also known as Big Santa Anita Dam, was constructed between 1925 and 1927 in response to continual flooding in the basin. There had been 11 catastrophic floods over a 90-year period, but the flood of 1914 resulted in damages in excess of $10 million. That led to the formation of the Los Angeles County Flood Control District and the Santa Anita Dam was one of 12 dams funded through the issuance of a $35 million bond in 1924.

The Santa Anita Dam that resulted is 230 ft. high, 550 ft. long at the top, 61.5 feet thick at the base and seven feet thick at the crest with a capacity to hold 1,500 acre feet of water (about 500 million gallons). The construction was completed at a cost of $1.2 million.

A storm in March of 1938 caused spillage over the top of the dam which led to improvements of the riser-valve system and other release aids which were accomplished over many years, including the construction of the tunnel in 1968.

In a section of the report entitled "Aesthetics—Direct Impacts, Cumulative Impacts" suggests that "The short-term aesthetic impacts during construction would be minimal…"  the EIR states, but terms some of the environmental impact of the work "unavoidable". 

The Santa Anita Dam Riser Modification and Reservoir Sediment Removal Project received full approval from all involved agencies on June 9, 2009.  The Los Angeles Board of Supervisors also approved the project, but temporarily delayed the project a minimum of 30-days on Dec. 7 of this year after objections to the oak tree removal were raised. Since that date, the DPW has reviewed alternatives to the plan. The agency issued a new report to the Board of Supervisors on Thursday.

According to the DPW's new report, "Any further delays to the approved project will result in increased risks to thousands of homes, businesses and schools in the communities protected by the dam."

Currently, removal of the trees is scheduled to begin Wednesday.