There was an audible sigh of relief and a burst of applause when Marty Adams, Director of Water Operations with DWP, announced last Tuesday night that the Department of Water and Power has found a non-potable water source for refilling Silver Lake reservoir. The refill will begin on May 1, 2017, he said. The reservoir will have been empty for over a year by then, due to a major construction project that DWP undertook to create a covered reservoir in Griffith Park replacing Silver Lake reservoir as a source of drinking water to comply with new state regulations. David Ryu and Mitch O'Farrell, City Council members whose districts divide the lake down the middle, promised to hold DWP to the May 1 refill date.
The big news was that DWP has found "a water resource we are physically losing," Adams says, in the form of groundwater in DWP wells in nearby Atwater that currently is going out to the ocean. The water will come from two wells that were taken out of service due to possible contamination in the 1980's. A water treatment plant opened in 1999 that can now treat some of that water.
Adams said that this water could be captured by replacing an antiquated pipe on Fletcher Drive which needs to be replaced anyway, then diverting the water into the reservoir thorough the new 8-inch pipe. The use of such a small pipe would result in a slow refill. It would take 6 months to cover the bottom of the lakebed and 12 to 18 months to fill the entire reservoir to the 440-foot historic level, Adams said.
Many questions remain to be answered, the first of which is how did this untapped surplus water solution avert discovery until this late in the construction process? But that may be water under the bridge at this point if the process goes forward.
Beyond refilling the reservoir, there are several engineering components still to be figured out. First, the water source needs to be tested further to be sure it is safe to use. It may need some treatment, but Adams says that early tests have deemed it "safe enough." Some device needs to be constructed and installed in the lake bed to ensure that the water moves around enough to prevent it from becoming a breeding ground for mosquitoes and other insects, or otherwise turn stagnant. The solution may be something similar to the fountain that shoots water into the air at the Echo Park lake.
"Managing mosquitoes and midge flies is a big thing," Adams says. Adding fish to the reservoir or bat houses are valid things to look at in the future to mediate insect growth.
The meeting went smoothly mainly because DWP seemed to have finally done some homework and found a viable water source, and also because any questions or comments about the future plans for the space surrounding the reservoir were tabled until the next community meeting in November. Adams did mention something in passing about DWP being open to breaking down or removing a portion of the asphalt walls of the reservoir. This will become an issue down the line because it goes straight to the heart of what constitutes "beautification" and also opens a whole can of worms as far as whether an environmental impact report, which can take a year to complete, must be done or if a simpler CEQA (California Environmental Quality Act) permit, which could possibly be okayed within 30-60 days, would suffice. Adams said that breaking down the walls is something DWP is not anxious to do, but would consider if the community resoundingly votes to do it. If, however, a time-consuming EIR is needed DWP would not be interested in pursuing the idea.
With any engineering project, it is hard to believe such an endeavor would not add months of construction and more questions about how much asphalt to remove, where to put it (in the reservoir? hauled away?) and how to be sure the water would not then erode the banks if there was no asphalt to keep it intact.
November is when those issues will be more fully explored and hopefully DWP will have more information at that time about what exactly would need to be done to the groundwater going into the reservoir, whether simply painting the concrete sides would be enough beautification for the short term and how they plan to move the water around to prevent the spread of mosquitoes and other insects.
Adams, who has worked with community groups on the Silver Lake reservoir for many years, indicated that the DWP is "very much on track" with the refill plans.