Hole in the Bucket
Cal Am doesn’t squeeze all it could out of aquifer storage and recovery.
Thursday, January 31, 2013
De-salting seawater is one of the most expensive ways to supply the Monterey Peninsula. According to California American Water estimates, its proposed regional desal plant would produce water at more than $5,000 per acre-foot. The more Cal Am can supplement desal with cheaper means, the less ratepayers will see their water bills spike.
A key component: aquifer storage and recovery (ASR), which takes extra water from Carmel River wells during high winter flows and injects it into the Seaside Basin for use in the dry season. The resulting water, produced by a partnership between Monterey Peninsula Water Management District and Cal Am, costs about $1,700 per acre-foot, by the district’s estimate. (Cal Am puts the number $500 to $1,600 higher.)
But a series of glitches – mechanical, operational and weather-related – have reduced this year’s ASR output to 45 percent of what it would be if all three completed wells were running the way they should.
This season’s ASR began Dec. 3 and paused Jan. 16, when Carmel River flows dropped too low to continue. In those six weeks, almost 195 acre-feet were injected into the Seaside Basin.
But an update presented to the district water board Jan. 30 finds that if the three ASR wells had been maximized, Cal Am could have injected 660 acre-feet in that time frame. (A fourth ASR well was recently built but is not yet connected to electrical and water lines.)
Why is the program falling short? One ASR well, according to the report, is out of service while Cal Am repairs broken shaft bearings. An equipment glitch at a river source well couldn’t be fixed due to wet conditions. Cal Am system demand spiked at times, reducing the amount of water that could be diverted to ASR. And several upper-river source wells stopped working when temperatures dropped below freezing earlier this month. Cal Am also missed several days of ASR production at the beginning of the season because its production wells were not ready, according to District General Manager David Stoldt.
Some factors, like demand spikes and an offline well, are beyond Cal Am’s control. But water board director Kristi Markey blames Cal Am for others – like failing to insulate its pipes before the temperatures dropped, and not being ready for the December rain.
“I’m disappointed with Cal Am falling down on the job here,” she says. “We can’t afford to lose the opportunity to add to our water supply.”
Cal Am spokeswoman Catherine Bowie maintains the company isn’t at fault. Cal Am was ready for the agreed-upon Dec. 3 start date, she writes by email, and even precautionary actions couldn’t prevent the cold-weather impacts. The pump failure that took the largest ASR well offline was unplanned, she adds, but it’s being repaired on schedule.
“In our water system, as in any water system, there will be mechanical failures and main breaks that occur,” she writes.
Stoldt says Cal Am is honoring the terms of its ASR agreement with the district, which puts the water company in charge of day-to-day operations. The district owns the original ASR facility, monitors the river and oversees the program.
“This has been a very good learning season,” Stoldt says. “You can’t just let water flow down that river that could be sequestered in the Seaside Basin. We’ve got to get better at it, and that goes for both parties.”