Colorado River

San Francisco based Current TV brings us this excellent, short piece on Lake Mead and the threat of it drying up.

World Without Water airs weekly on Current TV and is currently focusing on water resource issues.

[Via Digg and Current TV]

During a discussion at lunch on climate change, the Colorado River and the impact on water resources in the Southwest, one of my colleagues reminded me of this article published in the NY Times Magazine in October of 2007. It’s a fascinating (and rather grim) look on the future of water resources in the United States.

Climatologists seem to agree that global warming means the earth will, on average, get wetter. According to Richard Seager, a scientist at Columbia University’s Lamont Doherty Earth Observatory who published a study on the Southwest last spring, more rain and snow will fall in those regions closer to the poles and more precipitation is likely to fall during sporadic, intense storms rather than from smaller, more frequent storms. But many subtropical regions closer to the equator will dry out. The models analyzed by Seager, which focus on regional climate rather than Colorado River flows, show that the Southwest will ultimately be subject to significant atmospheric and weather alterations. More alarming, perhaps, is that the models do not only concern the coming decades; they also address the present. “You know, it’s like, O.K., there’s trouble in the future, but how near in the future does it set in?” he told me. “In this case, it appears that it’s happening right now.” When I asked if the drought in his models would be permanent, he pondered the question for a moment, then replied: “You can’t call it a drought anymore, because it’s going over to a drier climate. No one says the Sahara is in drought.”

I figure this article is apropos, especially because of the recent news of the future of the Colorado River that we posted about last week.

[Via NY Times Magazine]

The once mighty Colorado River, a source of drinking and agricultural water for much of the Southwestern United States is severely threatened by the effects of climate change according to a report by the USGS. Researchers there say that a small temperature increase of about 0.9 degrees Celsius would reduce the average flow of water in the river to its lowest flow in nearly 500 years.

Source: James Neely on flickr.

A “modest” 0.86 degree Celsius (1.5 degree Fahrenheit) increase in the 21st century could trim the average flow of the river — the primary water supply for residents in much of the U.S. Southwest — to the low end of a range marked between 1490 and 1998, USGS scientist Gregory McCabe said yesterday.

The Earth is likely to warm by more than twice that amount in the period, Rajendra Pachauri, chairman of the United Nations Intergovernmental Panel on Climate Change, said last month. McCabe will brief Congress on the findings in June, when legislators expect to debate plans for the world’s largest producer of greenhouse gases to begin capping its emissions.

“A 2-degree Celsius warming pushes the risk so high that it’s beyond anything that has happened in the last 500 years,” McCabe said on a conference call yesterday. “The average flow in the Colorado drops to lower than anything we’ve seen.”

[Via Bloomberg.com]

The latest edition of the USGS Corecast has been posted today and features a video of the Glen Canyon Dam High Flow experiment. There is some impressive footage and it’s a well put together video. Check it out. (Warning: Link goes to Quicktime Movie)

Preliminary analysis indicates that last week’s manmade flood of the Grand Canyon was a success. The three day flood redistributed sediment in the canyon, modifying old sand bars and creating many new ones as well (some of which are the size of football fields).

From the article:

During the flood, flows in the Grand Canyon increased to 41,000 cubic feet per second for nearly three days - four to five times the normal amount of water released from the Glen Canyon Dam. Water levels along the river rose between 2 and 15 feet and left sediment behind when the four giant steel tubes releasing the water from the dam were closed.

Officials released similar manmade floods into the canyon in 1996 and in 2004.

But those floods actually resulted in a net reduction in overall sandbar size because they were conducted when the Colorado River was relatively sand-depleted, according to the U.S. Geological Survey. Officials believe this year’s flood will be beneficial because sand levels in the river are at a 10-year high and are three times greater than 2004 levels.

Whatever benefits come from this year’s flood, however, will be eroded within 18 months without additional floods every year to 18 months depending on the amount of sediment available, Martin said.

In its environmental assessment on Glen Canyon Dam releases, the U.S. Bureau of Reclamation calls for no other high-flow releases until after 2012.

The benefits of the flooding are obviously beneficial. It’s a shame they don’t actually have plans to do this every year (probably due to the demands that must be met by the Colorado River Compact).