Can plowing the soil actually REDUCE the dust that blows away?
And can it be possible to reduce the dust pollution in the Owens Valley while also INCREASING water deliveries to the Los Angeles area?
My mom sent me an absolutely fascinating story from the Los Angeles Times: New dust-busting method ends L.A.'s longtime feud with Owens Valley
The story describes a technique which certainly falls into the "seems too good to be true" category:
The new solution is relatively inexpensive and nearly waterless, DWP officials said. It involves using tractors to turn moist lake bed clay into furrows and basketball-sized clods of dirt. The clods will bottle up the dust for years before breaking down, at which point the process will be repeated.The method was first tested in the early 1990s, then tabled out of concern the furrows and clods would disintegrate after a few rains. Two years ago, the DWP resurrected the idea and tested it on several acres of lake bed, but on a much larger scale, with furrows 2 to 3 feet deep. The results showed promise, provided the treated area has clay soil and flooding infrastructure in place.
Don't underestimate the stakes here: this is big business, and big money. And the other techniques that have been attempted over the previous quarter-century cost much, much more:
The new method will cost DWP customers about $1 million per square mile — three times less than shallow flooding. The cost of reducing dust with gravel, which has been applied to swaths of the lake bed, is about $25 million per square mile, officials said.The utility has already spent $1.3 billion in accordance with a 1997 agreement to combat dust over a 40-square-mile area, reducing particle air pollution in the region by 90%.
This represents dramatic progress for the Owens Valley, which has been struggling with these issues for 100 years.
Perhaps more importantly, the Owens Valley is probably the most-watched, most-studied, most-analyzed, and most-fought-over area in the water battles that occupy the entire Western United States.
So what happens in the Owens Valley doesn't just affect the Owens Valley; it affects fully one third of the country.
For example, consider this discussion about water issues in southern Nevada: Las Vegas and the Groundwater Development Project, which has an entire chapter entitled "Remember Owens Valley".
Not much grows on the exposed lakebed, and that’s where the trouble starts. There’s dust, lots of it. Sweeping winds come roaring down the valley and create tremendous dust storms. At times there’s so much dust and the visibility is so poor the locals call it the “Keeler fog” after the small remnant of a town on what used to be the lake’s eastern shoreline. Recently, a pilot followed a dust plume from the lake-bed all the way into the Grand Canyon.
Nothing about this process has been easy. A year ago, ARID Journal covered the controversy in detail: Particulate Matters: Settling the Dust on the Owens Dry Lakebed.
For the first 50 years that it diverted Owens River water to Los Angeles, the LADWP denied that dust was a problem on the river’s former lakebed. When in 1976 scientists at China Lake Naval Weapons Center in Ridgecrest, California, photographed clouds carrying an estimated 40,000 metric tons of fine alkali grit billowing out of the Sierra into the neighboring Mojave Desert foothills of Kern County, the LADWP claimed that Inyo County had some of the best air in the country and that, “there has been no substantiation of adverse health effects of alkali dust.” In 1987 the U.S. Environmental Protection Agency deemed the severity of the fine-grain pollution issuing from Owens dry lake as the worst in the country, outside of forest fire smoke, as often as 24 days a year. LADWP was on record that the land impacted by its water exports was “such a small area we think it is insignificant.
Over decades of study, multiple techniques were attempted:
More than a dozen suppression methods were considered in the lead-up to the first mitigation projects, including covering the lakebed in used automobile tires, but only three were eventually approved for widespread use: gravel cover, plants, and shallow flooding. Gravel, at $33 million per square mile to install, was deemed prohibitively expensive. Plant cover, most of which had to be salt grass, cost $15 million per square mile to install, then it needed irrigating. By far the cheapest immediate fix for a water company was to install bubblers to provide shallow flooding. LADWP estimates that the up-front cost of this was more like $12.9 million per square mile.
And the battle went on in the courts:
When a new dust abatement notice for 2.93 additional square miles arrived that summer, Nichols called in the lawyers in what has proved a sustained assault on the 1998 dust deal. Schade and Great Basin also went to the courthouse, filing suit against LA for non-compliance on an outstanding order. By October 2012, over in federal court, LADWP was suing Schade’s department, naming him personally as a capricious and rogue regulator, and also naming the California Air Resources Board, the US Environmental Protection Agency, the California State Lands Commission, and the federal Bureau of Land Management as colluders.
So when research by an Orange County landscape architecture firm named Nuvis came up with a new idea, it must have seemed like a fantasy at first:
Those decisions include widespread use of an as yet un-validated waterless dust control method called “tillage,” which will have to be approved by regulators including Schade before the meandering furrows shown in the Nuvis schematics could be plowed into the lakebed. “We’re hoping that tillage, basically like farm tillage, will be approved,” says Adams. “It costs about 10% of what it costs to do flooding. It’s a huge savings for rate payers.”
So, let's hope this this new technique actually works.
And let's hope that agencies across the west are able to learn from this, and spend less time (and money) fighting in the courts, and more time (and money) figuring out how to use water effectively without destroying the land.
And let's all say a big thanks to Ted Schade.
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