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Questions bubble to surface over use of water at Owens Dry Lake |
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Thursday, 20 November 2008 |
 The Sierra range is reflected onto a portion of the Owens Lake submerged in water by a regiment of shallow flooding meant to suppress harmful dust on the surface of the dry lake bed. Shallow flooding is one of three accepted dust control methods the Los Angeles Department of Water and Power has at its disposal, though it recently received permission to try a fourth on a trial basis. File photo By Darcy Ellis
Editor 11-18-2008 Is water being wasted out on the Owens Dry Lake?
Or, at the very least, is there a more efficient way to suppress the toxic dust that whips off the notorious Southern Inyo playa during severe wind storms?
Those are but two of the questions ostensibly being asked today as Great Basin Air Pollution Control Officer Ted Schade makes a presentation to the Inyo County Board of Supervisors detailing the water amounts used on each of the Los Angeles Department of Water and Power’s dust mitigation measures at the dry lake bed.
The presentation is being made at the behest of the local Agriculture Resource Advisory Board, a citizens commission comprised of ranchers, LADWP lessees, business owners and representatives of local chambers of commerce.
The board had Inyo County Agriculture Commissioner George Milovich approach the supervisors on Nov. 4 with its request after coming to the conclusion that water – widely viewed as one of the most precious resources in the West – might be overused at the dry lake on shallow flooding and managed vegetation mitigation efforts.
The concern, Milovich explained Monday, is that with so much of LADWP’s Owens Valley water going to dry lake mitigation measures – approximately 19,200 acre-feet alone (or 6,256,339,200 gallons) for shallow flooding of 26 square miles (16,640 acres) – the utility will be forced to cut back on the amount of water it sets aside for in-valley uses. (LADWP estimated upon the release of its 2007-08 Operations Plan that its water use on the lake, for both shallow flooding and the maintenance of managed vegetation, would increase to about 54,000 a.f. a year. In 2007-08, the amount of water used for in-valley uses – 103,650 a.f. – almost matched the total being sent down the aqueduct, without counting the large volumes targeted for Owens Lake dust control efforts – making it perhaps the first time in history that the Owens Valley used more of LADWP’s local water than the City of Los Angeles.)
Los Angeles is currently responsible for controlling dust on 42.7 square miles of lake bed identified as the biggest problem areas by the Great Basin Air Pollution Control District. The first 30 square miles were completed by the Dec. 31, 2006 deadline established in the 2003 State Implementation Plan signed off on by both Great Basin and LADWP.
According to Schade, LADWP implemented all three currently accepted mitigation measures on those 30 square miles: 26 square miles (16,640 acres) were treated with shallow flooding; about four square miles (2,200 acres) were planted with managed vegetation (salt grass); and less than one-tenth of a square mile (about 50 acres) was treated with gravel.
In surveying the progress of the dust mitigation in late 2005, Great Basin decided LADWP should expand its project, and after a court battle and settlement agreement reached in the fall of 2006, LADWP is now embarking on mitigation of an additional 12.7 square miles.
Schade said Monday that LADWP contractor Barnard Construction (awarded the bid this past summer) began construction two weeks ago on what will become another 9.2 square miles of shallow flooding, which, according to lake bed engineers, will require an additional 7,066 a.f of water (or 2,302,463,166 gallons).
According to Schade, Great Basin is allowing LADWP to try the “moat and row” method on 3.5 square miles with the caveat that it only gets one shot at fixing the project should the method prove ineffective. Schade noted that “moat and row,” essentially a series of ditches and berms resembling a giant waffle-like grid, “is unproven on a large scale,” which is why LADWP is only being allowed to implement it on a trial basis.
“They have one chance to fix moat and row and make moat and row work,” Schade said. “I call it ‘the two strikes and you’re out rule.’ After that, they have to go back to one of the three approved methods.”
If, however, moat and row “works famously,” then LADWP can petition Great Basin to have the method added to the current “menu” of mitigation options, which Schade explained the air pollution district allows LADWP the freedom to work from without too much interference.
That’s one reason why the Agriculture Resource Advisory Board is questioning the need for so much water usage at the dry lake, particularly if no one is telling LADWP how much it can and cannot use – or that it even needs to implement shallow flooding at all.
“We give them the menu and they decide how to fix the dust,” confirmed Schade.
The questions began bubbling to the surface, according to Milovich in his Nov. 4 memo to the Inyo supervisors, when members of the ag board took a recent field trip to the dry lake as part of its “intention to ensure that the least of amount of water is used by LADWP for purposes other than agriculture.”
It was in talking with engineers at the lake bed that the representatives learned about the potential overuse of water, and moat and row option.
Milovich’s memo reports that current data from L.A.’s engineers “have shown trials of moat and row to be effective and at the same time appear to use the least amount of water compared to flood irrigation at 4 a.f. and even shallow flooding at 1.2 a.f. per acre.”
That news brought hope to the Agriculture Resource Advisory Board, which noted that water not sent down the aqueduct must be purchased elsewhere to meet the needs of the L.A. system, making LADWP less likely to devote as much of the resource to its lessees for uses such as irrigation.
And less irrigation hurts not just Inyo’s growers and ranchers who depend on the practice for their livelihoods, Milovich said, but the valley as a whole – economically and aesthetically.
Agriculture is the county’s second largest industry behind tourism, bringing in just shy of $20 million in 2007, according to the 2007 Annual Crop and Livestock Report.
“The Ag Board is concerned about lessees being squeezed as far as their irrigation water,” Milovich explained, “which would mean no more green lands. They’re the ones who irrigate the valley (and are responsible for the scenery we all enjoy). If it wasn’t for the ranchers irrigating, there wouldn’t be any greenery.”
Milovich said the Agriculture Resource Advisory Board’s interest in the use of water at the dry lake “is about protecting the valley as a whole,” and is meant to inspire leaders and concerned citizens to take “a big-picture view of the valley.”
Some concerned citizens already taking an interest are local wildlife advocates, who contend that any reduction in water at the Owens Dry Lake should not come at the expense of the newly revived and thriving riparian habitats.
“No one argues on the need to use water responsibly at Owens Lake,” local advocate and birding authority Mike Prather said in an e-mail Sunday. “However, my concern, as a supporter of wildlife, is that the opportunity to balance the needs of wildlife at Owens Lake (a California public trust) and the needs of water for Los Angeles must not be missed.”
Prather explained that the “enormous wildlife population” at Owens Lake was lost 80 years ago when LADWP drained the lake, and it shouldn’t be allowed to be lost a second time. “This is the largest wildlife resource in Inyo County and it holds such potential for wildlife viewing,” he continued. “Water for wildlife is not ‘a waste.’”
Milovich was quick to point out that no one on the Agriculture Resource Advisory Board is “opposed to wildlife,” or dust mitigation, for that matter.
He noted that “it’s always good to bring out more dialogue and more truth.”
That’s exactly what Schade hopes to do with his presentation today, as he provides more specific numbers related to water use and each dust mitigation measure.
His presentation is set to begin at 10:30 a.m. in the Board of Supervisors room in the County Administrative Center in Independence. LADWP is expected to follow with a workshop/presentation of its own at a future meeting.
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Last Updated ( Tuesday, 16 December 2008 )
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