On a normal day in a normal year, a glass of water poured from any tap in the Santa Clarita Valley contains equal portions of water pumped from local wells and water imported from melting snowpacks in the Sierra Nevadas.
Water availability and water scarcity over the last few years, however, spanning a five-year statewide drought, has thrown the ratio of local water to imported water out of whack.
On Thursday, members of Financial and Operations Committee of the Castaic Lake Water Agency will be presented water production charts that show the CLWA is slowly getting back to the normal years of half-and-half water – half imported, half pumped locally – but not this year.
A breakdown of water pumped from all the local wells this year shows an increasing reliance on imported water since January.
July’s figures of imported-to-local water mark the most pronounced imbalance in more than four years.
For example, the same glass of water poured from any tap in the SCV contained less than 10 percent of the water pumped locally compared to 91.1 percent of it being imported from Northern California.
Drinking that summer glass of water means you would have been drinking almost 100 percent melted snow brought down the Feather River, stored in Orville Dam and conveyed south by the California aqueduct to Castaic Lake as part of the State Water Project.
By contrast, looking at the amount of water pumped out of the ground locally mid-summer in 2013, three quarters of the water consumed in the SCV was imported.
The same was true at mid-summer last year when three quarters of our water originated from Northern California.
So, why after a record amount of rainfall witnessed this past winter in the SCV do we rely so heavily on imported water?
The answer, according to Dirk Marks who serves as the CLWA’s water resources manager, isn’t that there’s a scarcity of local water, but rather an abundance of water made available this year from through the State Water Project.
The Oroville Dam, the biggest dam in California, swelled to capacity this past winter.
“There was so much water state side that we urged water purveyors to use more of the imported water,” Marks told The Signal Thursday.
As well, local water officials found themselves compelled to use water already set aside for them by state officials.
One of 29 State Water Project contractors entitled to receive water from the Sierra Nevadas in Northern California, the CLWA serves as Santa Clarita Valley’s water wholesaler.
Every year state officials with the Department of Water Resources assess the Sierra Nevada snowpack, calculate how much water the melted snow will produce and allocate how much each of the 29 agencies should get.
The CLWA is entitled to 95,200 acre-feet of water. It gets only a percentage of this allocation, however, depending on how dry a given year is.
Emerging from a very wet winter, however, state water officials were able this spring to set aside 50,000 acre-feet of water for the CLWA.
How much water is that? It’s about 50,000 football fields each under one foot of water.
This water earmarked for CLWA use is called “carryover” water. And it can be shared.
Unlike managing water in a drought year, when every drop of water is needed and used, the agency couldn’t use its 50,000 acre-feet of “carryover” water this current year which saw more rainfall than average.
Consequently, about 35,000 acre-feet of water earmarked for the CLWA went unused.
State officials then took that unused water – called spilled water – and poured it back into their “pool of water” resources, making it available to all agencies contracted with the state to receive State Water Project water.
The unused water doesn’t get wasted, it just stops being water earmarked specifically for the CLWA.
“Regarding the spilled water, effectively 35,000 acre-feet of water was spilled,” Marks told The Signal in July.
“That doesn’t impact our overall reliability as we have more than enough water to meet this year’s demands and still into carryover for possible use in 2018,” he said.
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