The L.A. Department of Water and Power is moving ahead with a plan to temporarily drain the Silver Lake Reservoir as part of the construction of a new water pipeline.
Silver Lake residents received more details about this project earlier this week from DWP officials, who said work would not begin until late 2014 or early 2015, when the reservoir would be left emptied for about 12 months.
The completion of the project will mark the beginning of a new era for the Silver Lake and Ivanhoe reservoirs, which will no longer be used to store drinking water after more than a century of service. Instead, the reservoirs will be removed from the city’s drinking supply and be re-filled with non-potable water, possibly reclaimed or from stormwater run-off.
Despite concerns voiced by some residents about draining the reservoirs, “we are going to move forward with this,” said a DWP official.
While the DWP has taken steps to minimize the construction impact of the pipeline, the Silver Lake Reservoirs Conservancy, a nonprofit group dedicated to preserving the reservoirs and surrounding property, said that the agency needs to undertake “additional mitigations” to comply with additional the California Environmental Quality Act (CEQA).
“We will be giving full consideration to the plan presented at the June 19 Community Meeting, and will seek additional information and actions to ensure the project’s success,” said conservancy President Craig Collins.
The agency surprised many residents last year when they announced they were looking at a different approach for constructing an estimated 4,500-foot-long water pipeline. The pipeline – officially named the Silver Lake Reservoir Complex Bypass Pipeline – is part of the much larger project to replace the open-air reservoirs with giant underground tanks near Griffith Park to meet federal water standards. The project allows the reservoirs to remain open bodies of water.
Building about 3,000 feet of the pipeline on the bed of the reservoir instead of under neighborhood streets would prove less disruptive for residents and traffic as well as less costly – $27 million versus $73 million – and time consuming, according to agency officials. However, this approach requires temporarily draining the water out of the basin, which is surrounded by expensive hillside homes whose value is partly based on reservoir views.
The department promised to keep the heavily used walking path around the Silver Lake and Ivanhoe reservoirs open during construction by creating a detour onto reservoir property. The utility promised all construction vehicles will set-up inside the basin of the reservoir, which will take several months to drain, as opposed to near a nursery school on the north end of the property as in previous plans.
The new plan will still require the tearing up of nearby streets though on a smaller scale than under the previous proposal. About 1,600-feet of West Silver Lake Drive between Armstrong Avenue to Tesla and then from Tesla to Hawick Street will be dug up to install the pipe. While work is underway on Silver Lake Drive, traffic will be limited to one direction and Tesla will be used as a detour. The department said Tesla will remain a one-way street while acting as a detour.
Residents raised concerns about how dust generated during construction would be handled and minimized. Film producer Jerome Courshon took issue with the department watering a minimum of two times a day, pointing that state law requires the ground to be hydrated “as much as necessary.” The department said they will look into methods of testing air quality during the construction project.
Other topics raised at the meeting:
- The agency said will avoid disturbing herons, which live in trees near the reservoir, and keep construction in those areas to a minimum around nesting season.
- According to the department, construction is allowed between 7 a.m. and 7 p.m. in the Silver Lake area, but most contractors end the day around mid-afternoon.
- Engineer Rueben Rosales said the contractor will employ a plant-based soil binder approved by Caltrans to minimize airborne dust. The construction will install two pipes, one inside the other, to prevent the undrinkable water from entering the pipes.
- The construction of the 66-inch wide bypass pipeline, which include the year-long draining of the reservoirs, will take 18 months complete
The reservoirs will be refilled to their “historic levels” said one official. Some residents, however, called on refilling the reservoir to its brim or taking other measures to the improve the aesthetics of the concrete basin. Some attendees requested the utility use the money saved on the project to paint the interior of the reservoir and make it more pleasing to the eye.
But director of Engineering and Technical Services Susan Rowghani said filling the reservoir to the very top risked the structural integrity of the dam.
Designed by legendary engineer William Mullholand, the two reservoirs that serve as symbols of Silver Lake were built more than a century ago, with the smaller Ivanhoe reservoir completed in 1906 and the larger Silver Lake reservoir completed a year later, according to the Silver Lake Reservoirs Conservancy. The larger of the two reservoirs was named in honor of water commissioner named Herman Silver.
DWP officials are scheduled to present their plan for the bypass pipeline during the July meeting of the Silver Lake Neighborhood Council and during a project walking tour scheduled for Saturday, July 20 at 9 a.m. The tour will begin on West Silver Lake Drive just north of Moreno Avenue.