The risk assessment is integrated with the SECURE Water Act, legislation passed in 2009, in which Congress determined there should be a full-scale report on the Colorado's water supply.
According to the first report under the SECURE Water Act, "As the effects of climate change and snowpack are realized throughout the Colorado River Basin, these effects will drive changes in the availability of natural water supplies."
Earlier independent research also shows that with climate variability, risks to the precious Colorado water resources increase.
"Virtually all the climate models suggest there will be a reduction of inflows in the river. It could be 10 to 30 percent," said Tim Barnett of the Scripps Institution of Oceanography, who published a report on the Colorado River in 2009. "It's not a problem you can cavalierly say, 'We will worry about this in 20 to 30 years.'"
The year of a little relief
Lake Powell, largely in Utah, and Lake Mead, along the Nevada-Arizona border, account for approximately 85 percent of the Colorado River's water storage capacity. Wet years come as a huge relief to the reservoir managers, but when the lakes get low, tensions start to run high.
"We had such a large hole in that reservoir, such a large amount of available capacity, that the water has been very welcome," said Richard Clayton, who operates Lake Powell for the Bureau of Reclamation.
"It's been a banner year for us at Lake Powell. We're going to see over 50 feet of filling from the low point, and year over year, we're going to see a net gain of 20 feet," said Clayton. "It doesn't seem like much, but it is. It's great for recreation, power supply; there are a lot of smiles because of how wet this year has been."
There are only two years -- 1983 and 1984 -- that have had more unregulated inflow than in 2011. This stands in stark contrast to less than a decade ago, when in 2002, the flow was as low as it has ever been in the history of Lake Powell, beginning in 1963.
The spring runoff has been so great it has even overwhelmed some northern areas of the basin, where authorities are still trying to assess the damages caused by flows that were 160 percent higher than average. In some places, the water caused lowland flooding and bank erosion and lapped up against the underbellies of bridges, restricting access to roadways, said Aldis Strautins of the Grand Junction Weather Forecast Office in western Colorado. Over July, the water levels have steadily receded.
Farther downstream, Lake Mead is also experiencing high water flows and levels. However, the reservoir will still be only 57 percent full by December 2011. This will take it 50 feet higher than last year, when the lake was at an elevation of only 1,083.8 feet -- had it dropped to 1,075 feet, it would have triggered a shortage declaration and forced Nevada and Arizona to curtail their use of the Colorado River.
Still struggling to reach the Sea of Cortez
To curtail the drain on the Colorado River, there have been some improvements in consumption practices. The Southern Nevada Water Authority, for instance, created a Water Smart Landscapes Rebate, which has helped convert 150 million square feet of lawn in the Las Vegas Valley into water-efficient landscaping. The project has saved the area billions of gallons of water.
Conservation efforts have also led to overall savings. According to a report by the Pacific Institute released in June, 28 water agencies in five separate states delivered less water in 2008 than they did in 1990, despite population and industry growth.
But continued population increases, coupled with the drains of development, farming and recreation, plus the impacts of climate change, have meant that more conservation needs to take place while there's still time to do it.
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10 Comments
Add CommentYes, there is a serious problem. It is caused by blame. Global warming takes the blame for the problems caused by water rights, over grazing, and general land mismanagement leading to desertification. Make the people of Denver stop watering their lawns. End water rights. Hold back on some of the water upstream as nature and beavers used to do before white man came. Then the land will recover.
Reply | Report Abuse | Link to thisAll of those are problems. Climate change needs to be factored in as well as all other impact factors so that loss of water is less than the river's natural recovery rate.
Reply | Report Abuse | Link to thisIf you choose to live in a desert, why would you expect to have a green lawn anyway? That never made sense to me.
Denver is on the other side of the Continental Divide. Look at a map. My so-called "over-grazing" is what provides your food. Also, most of the Colorado Basin's lands have been deserts for thousands of years. The ONLY part that isn't desert is the Rocky Mountains. And what don't you understand about the "RIGHTS" associated with water rights? Basic water rights are an area of the law that hasn't been altered in centuries. My water rights were created over a century ago. Beavers create dams to provide a safe place to raise their families. Have you ever seen Lakes Powell and Mead? They are probably larger than the county that you live in.
Reply | Report Abuse | Link to thisAs a rancher in western Colorado, I despise you people that spew blame without knowing ANY facts about the situation. EVERY SINGLE THING THAT YOU SAY IS ABSOLUTELY WRONG! Local weather, and the climate in general, are changing. We need to adapt.
Now we know why the Anasazi civilization ended, and they didn't have 30 million people living off the limited water supply. The Southwest has always had droughts and likely always will. We may not be able to limit population growth, but mother nature surely will.
Reply | Report Abuse | Link to thisWell nostalic since you are a Colorado rancher, I guess you know more than I do. I therefore assume that Denver does not have water rights to the Colorado river and does not get municipal water through the Colorado-Big Thompson project which sends water over the continental divide. I guess that the area has always been desert and John Wesley Powell was wrong when he described what would happen if the area did not hold back its water and reuse it but instead shipped it out of the area. Thus, there would no point in restoring the land to what once existed. Xeriscape and drip irrigation make no sense to you.
Reply | Report Abuse | Link to thishubert says: "Make the people of Denver stop watering their lawns."
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Hmmmm......while hubert likes to point fingers and assign "blame" in this instance, he really needs to understand that Denver is on the eastern side of the Continental Divide, and that the Colorado River Basin is on the western side, flowing AWAY from Denver!
notslic says: "Local weather, and the climate in general, are changing. We need to adapt."
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This is very true, and climate change is already giving us more El Nino and La Nina winters, and it was the La Nina pattern this past winter that deposited more snow in the north-central mountains of Colorado, while generally sparing the southwestern part of the state and the San Juan Mtns. All the lakes including Blue Mesa, Powell and Mead are still rising, but probably not for much longer:
http://snowpack.water-data.com/uppercolorado/index.php
Lake Mead hit a historical low level at the end of Nov. and has rebounded quite nicely, but even after all the record snowpack has melted, it will only be at 56%.
Lake Powell has risen 50 feet since its low in April.
I'd much rather see that Colorado snow being used as irrigation in western Colorado, than watering golf courses in the desert of Nevada!
BTW, where's that Olathe sweet corn we usually see by mid-July?
Thanks for the info about the C-BT Project, which was built between 1938 and 1957, providing supplemental water to 30 cities and towns. The water is used to help irrigate approximately 693,000 acres of northeastern Colorado farmland, and not sure if Denver is one of the cities that gets supplemental water from it or not. I do hear from time to time that Denver does indeed invoke water restrictions on its residents, but probably not this year with a good snowpack and good monsoonal flow.
Reply | Report Abuse | Link to thisHi Lakota. Sweet corn is armpit high. You'll see it soon. Almost an inch and a half of rain so far in July!!! This is the latest that I can remember my irrigation ditch being so full and dirty. That IS good news about Mead and Powell. But, as it says in the article, they need a few more years like this one to make a real difference.
Reply | Report Abuse | Link to thisSince Hubert knew about the Big Thompson, and put down Denver, he probably lives in the Fort Collins area. I understand why he is so upset. It used to be a nice mellow farming community back in the 70's when I went to CSU. Now it is solid city from the Springs to Wyoming. Definitely the wrong side of the Rockies. As far as I know, Denver gets its water from the Platte drainage.
Cheers
Re: "The study is based on data from historically observed and paleo-reconstructed water flow records, as well as projections from global climate models."
Reply | Report Abuse | Link to thisHistorical observation is empirical; climate models would seem to indicate inherently-biased computer simulations (i.e., output from the computer is only as good as the data entered). What is the procedure to paleo-reconstruct water flow records?