From the Switchboard (Theo Spencer):
The Interior Department earlier this week released a long-awaited study on future water supplies from the Colorado River Basin. The news was not good…
The report identifies drought/climate change and population growth as the main causes of the water shortage (good Los Angeles Times story here). Droughts obviously lead to less water and droughts are connected to/made worse by climate change…
However the report does not reach a specific conclusion, instead it kicks the can down the road. But the good news is cities and states are already taking action to address water shortages. Cities like Las Vegas and states like California offer good example of how to deal with shrinking water supply through cost-effective and expeditions practices like efficiency and regional planning. California has the single largest allocation of water from the Basin.
From Circle of Blue (Brett Walton):
The landmark study — the most comprehensive water study in the department’s history — revealed a “troubling trajectory,” Salazar said. The arid basin, which provides water to an area in which 40 million people live, will become drier, more densely populated and — even with new supply projects — more vulnerable in terms of water reliability, hydroelectric power generation, recreation, and river flows.
The median gap between supply and demand is 3.2 million acre-feet by 2060, or nearly 25 percent more than the forecasted annual flow when accounting for climate change, and most of the growth in demand will come from cities and industries.
“There is no one solution,” Salazar said. “We need to reduce demand and we need to consider increasing water supply through practical measures.”
The mix of solutions — and what makes one “practical” — is the most disputed section of the study. The Bureau of Reclamation, the lead agency, evaluated 30 options and slotted them into four “portfolios” based on water supply reliability, technical feasibility, and energy- and carbon-intensity.
Excluding the projects with low reliability or tremendous technical challenges, the basin could increase its water supply by 7 million acre-feet by 2060 at an annual cost, in 2012 dollars, that ranges from $US 2 billion to $US 7 billion. Those cost estimates are quite uncertain and are best used as a relative figure to compare options, not as an absolute number for what the actual cost might be, said Carly Jerla, a study co-manager and an engineer with the Bureau of Reclamation’s Lower Colorado office.
From The Washington Post (Brad Plumer):
There’s a fair bit of uncertainty here — climate models still disagree on how sharply annual flows will drop in the future. And population growth is hard to predict. Some environmental groups have even suggested that states might be exaggerating their projected growth to qualify for more federal money for big infrastructure projects.
That said, the best estimates suggest that demand will continue to outstrip supply, much as it has in the past decade. By 2060, the report says, the median shortfall could reach 3.2 million acre-feet (or about five times as much water as Los Angeles uses each year). The amount of irrigated farmland is also expected to shrink.
When scientists talk about the need for “climate adaptation,” this is what they mean. So how are these states going to deal with the water problem? The report has an in-depth analysis of different adaptation options, grouped into a few broad categories:
–Importing water from elsewhere. The report examined a bunch of zany proposals for bringing more water to the basin. One idea is to build a massive 600-mile pipeline from the Missouri River down to Denver. Sure, it would cost many billions of dollars and require large new power plants to pump the water, but why not? Or maybe ships could tow freshwater icebergs from the Arctic down to Southern California! Sadly, the report concluded that many of these schemes are unfeasible for now.
–Desalination. Another idea: If the fresh water’s running out, why not set up some desalination plants to treat brackish water or seawater? There’s already a $150 million desalination plant operating in Yuma, Ariz., to recycle salty irrigation water. The report doesn’t rule this out, though these plants are pricey and would likely only be built in severe shortages. (What’s more, desalination plants use a lot of energy, which means more carbon emissions, which worsens the problem… )
–Conservation and reuse. This is the option environmental groups tend to prefer, and there are dozens of different strategies here. Cities can recycle their “grey water,” (say, using old bathwater to flush toilets or water golf courses). Land managers could kill off thirsty plant species like the tamarisk. Water managers could slow the pace of evaporation by placing covers over reservoirs and irrigation canals. Governments could even set up a system in which users trade water permits.
From The Kansas City Star (Dave Helling) via McClatchy:
Among the study’s conclusions: Importing billions of gallons of water from the Missouri River, as an anonymous Westerner suggested nearly a year ago, would be massively expensive and take decades to pull off. The report didn’t rule out the option, giving it high marks for the amount of the water it would provide and its “technical feasiblity.” But high electricity costs and a 30-year permitting and building schedule prompted the Bureau to give the idea a low rating compared with other water-generating and water-saving possibilities.
Department of Interior Secretary Ken Salazar said the trans-Kansas pipeline hurdles were likely too high to overcome. Instead, in a conference call Wednesday, he urged thirsty westerners to focus on “solutions that are out there that will help us.”
The Bureau’s report, and Salazar’s comments, are likely to bring a sigh of relief from officials along the Missouri River basin, and as well as several “I told you sos.”
Almost to a person this week, interests along the Missouri River said the political, legal and practical problems associated with the pipeline made its construction highly problematic. “The political hurdles to overcome are gigantic,” said former Kansas Gov. Mike Hayden, now director of the Missouri River Association of States and Tribes. “The likelihood is very, very slim.”
The trans-Kansas water pipeline was one of dozens of suggestions submitted last winter after federal officials asked westerners for advice on their region’s chronic water problems.
More Colorado River Basin coverage here and here.