Time to get ready for the runoff

June 6, 2011

As temperatures begin to warm in the Sierra, snow will melt, sending runoff down Bishop Creek (above) and into local streams and ditches. Residents are being advised to clean debris from their ditches and streams to prevent water from spilling over the banks. Photo by Darcy Ellis

With a heavy snowpack lingering in the Sierra, residents in Inyo County are being advised to clear their ditches and ponds to prepare for the inevitable influx of water as summer temperatures begin to creep into the Owens Valley.
According to Los Angeles Department of Water and Power Public Information Officer Chris Plakos, the department is doing its part, with crews working daily to ensure ditches are ready for the runoff.
The LADWP said it is anticipating 619,000 acre-feet of runoff to make its way down from the Sierra this spring and summer. That is 150 percent of the average runoff. To be clear, one acre-foot is 326,000 gallons of water.
“Our crews are out working almost every day to make things go smoothly,” Plakos said.
Each year, the Inyo County Sheriff’s Department, LADWP and the Bishop Community Water District remind residents to clear their ditches, streams and ponds to prevent flooding as the runoff makes its way to the valley floor. That advice is as important as ever this year.
If ditches and streams become clogged with debris, this year’s runoff could cause significant flooding.
“The runoff really has not started yet,” Plakos said. “Mammoth and Rock Creek (snowpacks), they’re still holding steady from last month. People need to keep their ditches clean and be courteous and aware of their neighbors downstream.”
Inyo County Sheriff Department Public Information Officer Carma Roper said sheriff’s personnel will be meeting with LADWP and other local and state agencies on June 2 to discuss potential for flooding due to the runoff.
Plakos said that the draining of South Lake should not add any additional water to local streams and ditches, as Southern California Edison, who is responsible for water flow in and out of the lake, has the ability to regulate the amount of water that flows into Bishop Creek and makes its way into the valley.
“The thing that can really be an issue is if we get a warm rain on the snowpack, because that makes a kind of sludge,” Plakos said. “If we got 100 degree temperatures in Mammoth tomorrow, the snow wouldn’t melt fast enough to cause any major problems, because our system is built to handle the worst-case scenario.”
Right now, Plakos said Crowley Lake and other department-owned reservoirs are at the optimal level to receive and hold heavy runoff flows. “Our systems can certainly accommodate a runoff year like this,” he said.
With the LADWP and Edison prepared for the heavy runoff, local officials want to make sure that local citizens are also prepared.
Any excess plant growth, debris and sediment in private ditches should be cleared as soon as possible to prevent flooding this summer. v