January 08, 2014

Requiem for a river: The Colorado

Lake Mead and its infamous bathtub ring, behind Hoover Dam./NYT photo
Good piece here from the New York Times, especially for Easterners unfamiliar with how overtapped the Colorado River already is, and its likely future.

Its likely future? For the man-made version of the river, in which almost none of the river flows "free" below Grand Canyon, and almost none ever reaches the Gulf of Mexico? Grim.

And getting grimmer.

The keys to the central and lower Colorado are two massive dams, Glen Canyon and Hoover, starting from upstream to downstream, and two massive (for now) man-made lakes behind them, Powell and Mead, respectively. (The two are, respectively, the second-largest and largest man-made lakes in the U.S.)

Mead, with both its water supply and its dam being closer to major user areas, and being the older of the two, is the biggie. And, "getting grimmer" indeed:
Lake Mead currently stands about 1,106 feet above sea level, and is expected to drop 20 feet in 2014. A continued decline would introduce a new set of problems: At 1,075 feet, rationing begins; at 1,050 feet, a more drastic rationing regime kicks in, and the uppermost water intake for Las Vegas shuts down. At 1,025 feet, rationing grows more draconian; at 1,000 feet, a second Las Vegas intake runs dry. 

But, Powell isn't off the hook.
Lake Powell is another story. There, a 100-foot drop would shut down generators that supply enough electricity to power 350,000 homes.
The story notes how the early 20th century was, as we now know, far wetter than normal, and thus water appropriations in the seven states of the upper and lower Colorado basins were "oversold." Sometimes massively so.

And, here's another part of the problem. Let's call it the "ostrich effect."
The federal Bureau of Reclamation’s 24-month forecasts of water levels at Powell and Mead do not contemplate such steep declines. But neither did they foresee the current drought. 
But, BuRec, as it's known out west, has no excuse for making such over-optimistic forecasts — other than pandering to all of the river's overallocated water users.

A fellow federal agency, the National Weather Service, says so. Per maps at the link, the Southwest is supposed to be above average on temperatures for all of 2014. (So much for the climate change denialists.) And, precipitation is supposed to be average through May. Given that, especially in the upper basin, the majority of precipitation is winter snow, this is a biggie.

Given that other research has said, per the Las Vegas Review-Journal, there's a 50-50 probability at least one of the two lakes hits "dead pool" by 2021, and that they hit minimum electric power generation by 2021, pandering to overallocated water (and electric) users is long past its expiration date.
The report unveiled Tuesday by the University of California-San Diego's Scripps Institution of Oceanography places Lake Mead's chances of running dry by 2021 at 50 percent, better than your odds of winning at any casino.

According to Scripps researchers, there is also a 50 percent chance that reservoir levels will fall low enough to shut down power generation at Hoover Dam by 2017, and a 10 percent chance the lake could be dry by 2014.

But the study's co-author, Tim Barnett, said those doomsday dates aren't as important as the overall message.
"The point is this is coming in 10 years, not 20 or 30 or 40. We're looking it in the face now," said Barnett, a research marine physicist who wrote the paper with climate scientist David Pierce.
Indeed. Pandering to users is long past its shelf life. The original report, here, has more detail. That's especially true since the report is now more than 5 years old and BuRec keeps its head buried in the (ever-increasing) sand.

As for claims that this will never happen, per the Review-Journal story? The BuRec is being ignorant, probably willfully so, of past history. It took decades of ongoing suits before Arizona finally joined the Colorado River Compact. It took more suits before the Central Arizona Project took off. It took an international lawsuit PLUS the first Arab oil embargo before we as a nation agreed to guarantee any Colorado River water to Mexico.

The idea that we would never let either lake reach dead pool has about as much guaranteed truth value as the idea that we'd never kill off every one of those 100 million passenger pigeons.

And, it's not even dead pool. If Lake Mead falls just over feet this year, instead of 20 feet, water rationing starts. This year. Not some date in the future.

And, it's possible. Beyond above average temperatures predicted for the Southwest through at least mid-summer, as of right now, the Rockies' snowpack is, overall, average to below average. And, the West Coast is just bone dry. Here's the details.

Plus, it's not just water issues. Note the other issue — power generation at Hoover Dam could die by 2017. Even if Las Vegas has some water, do people want to live there with almost guaranteed summer brownouts? Also, the lower the lake sinks, and the lower you have to run tubes to get water out of it, the more electricity you have to use to pump it, as Las Vegas, at 2,000 feet, is well above the bottoms of those siphons.

And, soon enough, the pressure's going to come for more water to be released from Lake Powell. Besides the lawsuits that will trigger, that will cut electric generation there. Phoenix gets to duel with Las Vegas as to which one has more brownouts and blackouts, then.

The answer? Far beyond what the Times quotes federal and state officials as saying. Rather than bailing out people in Arizona, Nevada, and exurban L.A's Inland Empire when the housing bubble burst, we should have paid to move them back to the Midwest.

Instead, if the Central Arizona Project is indeed taken out of commission by, say, 2025, and another one-third of the Imperial Valley in California faces the same fate, Phoenix, in addition to becoming even hotter, will face another problem.

Those haboobs that tea partiers think are the name for a Muslim incursion? They'll be carrying more and more agrichemicals from fallow desert farmland to the west and dumping it in the Valley of the Sun. People who either moved there themselves, or had ancestors do so, for their lungs, will be living in one of the most unhealthy areas in the country.

There is a bit of schadenfreude here. The area around the Valley of the Sun, plus Orange  County and San Diego County in California, are hardcore red staters. Climate denialists. Swelter away in intermittent summer electricity, and croak away in diminishing water.

It's also a bit of caution for Texas. The Rio Grande involves international compacts and the Pecos has an interstate one. Even where rivers are all in Texas, like the Colorado of Texas, the ones that start in West Texas, as heat and possible drought continue, are under similar pressures. And, given how the current Texas government has far more ostrichitis on climate change than BuRec, they're likely to mismanage addressing that pressure even worse than the feds.

No comments: