Tag: Colorado River Basin

Study says global warming ups odds of Southwest megadrought

Heat-trapping greenhouse gases may dessicate Colorado River Basin

The paradox of water in the desert, illustrated by a NASA satellite image of the Colorado River.
Megadroughts ahead? Satellite photo of the Colorado River Basin via NASA.

Staff Report

It’s very likely the southwestern U.S. will be hit by droughts unlike any seen since the region was settled by Europeans. Global warming has driven the odds of a 10-year drought to at least 50 percent, and the chances of a 35-year megadrought range from 20 to 50 percent during the next century, according to a new study led by researchers with Cornell, the University of Arizona and the U.S. Geological Survey.

Global warming is “weighting the dice” for megadroughts, said lead study author Toby Ault, explaining that the buildup of greenhouse gases is shifting the climate dramatically. The study is set to be published in an upcoming issue of the  American Meteorological Society’s Journal of Climate. Continue reading “Study says global warming ups odds of Southwest megadrought”

Lake Powell April-July inflow was 94 percent of average

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Water storage in Lake Powell has hovered near 50 percent of capacity for the past few years. Photo via NASA Earth Observatory.

Wet spring and summer help avert worst of water shortages for now

Staff Report

FRISCO — Water storage in Lake Powell peaked on July 14 this year and has started its annual seasonal decline that will continue until spring runoff starts early in 2016, according to an Aug. 18 update from the U.S. Bureau of Reclamation.
Continue reading “Lake Powell April-July inflow was 94 percent of average”

Major Colorado River players announce conservation push

Near critical shortages in California prompt action

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Heading downstream … bberwyn photo.

By Summit Voice

FRISCO — With Colorado River water supplies disappearing at a dizzying rate, and with a thirsty — and politically mighty — California parched by drought, the biggest water users at the table said this week they’ll invest $11 million to try and conserve significant amounts of water across all sectors, including including agricultural, municipal and industrial uses.

The Central Arizona Project, Denver Water, The Metropolitan Water District of Southern California and Southern Nevada Water Authority all signed on to what is being presented as a landmark water conservation agreement aimed at demonstrating “the viability of cooperative, voluntary compensated measures,” according to a press release from Denver Water. Continue reading “Major Colorado River players announce conservation push”

Groundwater depletion threatens sustainability of Colorado River

Satellite data suggests more than 75 percent of water loss in drought-stricken basin is from groundwater pumping

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A new study quantifies groundwater depletion in the Colorado River Basin. Map courtesy U.S. Bureau of Reclamation.

By Summit Voice

FRISCO — Groundwater pumping is a huge factor in the Colorado River Basin water equation, California-based researchers said this week, announcing the results of satellite study that for the first time quantifies how groundwater contributes to the water needs of western states.

Along with surface diversions and pipelines, water users in the basin are also unsustainably depleting underground aquifers. For example, mountain resort towns in  Colorado tap underground water from headwaters streams like Tenmile Creek and the Blue River for municipal use.

The new study found that more than 75 percent of the water loss in the drought-stricken Colorado River Basin since late 2004 came from underground resources. The extent of groundwater loss may pose a greater threat to the water supply of the western United States than previously thought, the researchers concluded. Continue reading “Groundwater depletion threatens sustainability of Colorado River”

Environment: ‘Extreme’ dust-on-snow events can speed runoff in Colorado River Basin by six weeks

2013 brought record levels of dust to Colorado’s mountains

More frequent desert dust storms dropping pollution on the Rocky Mountain snowpack is one of the climate change impacts affect the high country.
More frequent desert dust storms dropping pollution on the Rocky Mountain snowpack is one of the climate change impacts affecting the Colorado high country.

By Bob Berwyn

FRISCO — Dust storms that darken the Rocky Mountain snowpack and speed snowmelt are becoming more extreme, according to new research. Particularly heavy dust-on-snow events can speed the melt-out of the snowpack by a full six weeks, all other factors being equal, said Jeffrey Deems, a researcher with the Western Water Assessment and the National Snow and Ice Data Center.

“In 2006 we were impressed at how much dust there was. Then 2009 turned up, and 2010, and 2013 was the dustiest year we’ve recorded in the San Juans,” Deems said, explaining that the latest study, put together by researchers with NOAA’s Cooperative Institute for Research in Environmental Sciences was aimed at updating previous work with data from those heavy dust years.

Last spring, on April 8, a single 16-hour dust storm dropped more dust on the San Juans than the annual totals in any previous winter since scientists started taking detailed measurements, said Chris Landry, director of the Center for Snow and Avalanche Studies in Silverton, which tracks the dust-on-snow events via a network of observation sites. Continue reading “Environment: ‘Extreme’ dust-on-snow events can speed runoff in Colorado River Basin by six weeks”

Climate: How will the Colorado River flow?

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A NASA MODIS satellite image encompasses a view of the entire Colorado River Basin, from the headwaters in the Rocky Mountains, to the Gulf of California.

New study may help fine-tune future projections

By Bob Berwyn

FRISCO — Projections of future flows in the Colorado River have been all over the map, ranging from a 6 percent reduction in flows all the way up to a 45 percent drop.

Getting a better handle on that number is critical for water managers from Colorado to California, but fine-tuning models to address global warming impacts on the scale of a single river basin is a big challenge.

A new study by an interdisciplinary team of scientists from around the West doesn’t provide a definitive answer — but it does help explain why the estimates are so different and may help narrow the range in the next generation of climate models. Continue reading “Climate: How will the Colorado River flow?”

Climate: Another grim year for Lake Powell

“Slight improvement in the Colorado basin water supply is like expecting a road-killed jackrabbit to feed a whole pack of hungry coyotes. It’s not nearly enough to go around. ~USDA hydrologist Randall Julander

The last decade has been rough for a key reservoir in the intricate water storage system that sustains much of the American Southwest. Lake Powell, a meandering network of flooded canyons in southern Utah, has seen inflow rates from its key tributaries dwindle due to severe drought. Inflow between 2000 and 2012 has been the lowest 13-year period on record since the lake was created in 1963. A welcome surge of water arrived in 2011, but 2012 was a near-record dry year. And 2013 isn’t looking much better. Meteorologists expect another dry year, and hydrologists are forecasting that the combined inflow of 2012 and 2013 will be the second lowest on record (trailing only 2001-2002). In early May 2013, the lake was 47 percent full. That is not a record low—the reservoir dipped to 33 percent of capacity in 2005—but U.S. Bureau of Reclamation forecasters expect Lake Powell to drop to 42 percent of capacity by September, the end of the water year.
A recent NASA satellite image shows low water levels in Lake Powell in Spring 2013. Click here to visit the NASA page. The last decade has been rough for a key reservoir in the intricate water storage system that sustains much of the American Southwest. Lake Powell, a meandering network of flooded canyons in southern Utah, has seen inflow rates from its key tributaries dwindle due to severe drought. Inflow between 2000 and 2012 has been the lowest 13-year period on record since the lake was created in 1963. A welcome surge of water arrived in 2011, but 2012 was a near-record dry year. And 2013 isn’t looking much better. Meteorologists expect another dry year, and hydrologists are forecasting that the combined inflow of 2012 and 2013 will be the second lowest on record (trailing only 2001-2002). In early May 2013, the lake was 47 percent full. That is not a record low—the reservoir dipped to 33 percent of capacity in 2005—but U.S. Bureau of Reclamation forecasters expect Lake Powell to drop to 42 percent of capacity by September, the end of the water year.

By Bob Berwyn

FRISCO — With May inflow into Lake Powell less than half the long-term average, the U.S. Bureau of Reclamation is projecting that total reservoir storage in the Colorado River Basin will dip to about 29.3 million acre feet. That’s just 49 percent of storage capacity and the lowest level since the peak of the early 2000s drought, when the 2005 water year started with storage at 29.8 million acre feet (50 percent of capacity). More Lake Powell water info here: http://lakepowell.water-data.com/.

May’s inflow into Lake Powell was  1,121 thousand acre-feet, about 48 percent of average — a stark reminder that winter and spring precipitation was well below average in large parts of the Colorado River Basin, despite a surge of late-season moisture in the headwaters region of north-central Colorado. But at least the May inflow was an improvement from April, when inflow was only about a third of average.

After releasing about 602,000 acre-feet downstream, Lake Powell’s elevation at the end of May was at about 3,599 feet, which is about 100 feet below full. According to BuRec, the reservoir elevation is expected to remain within several feet of the current elevation throughout spring and summer as inflow from runoff roughly matches reservoir releases. In late summer, the reservoir elevation will begin to decline again.

For the April to July runoff season, water managers are now projecint that total inflow will be about 3 million acre feet, which is about 42 percent of the average inflow for the 1981 to 2010 period, with the overall water supply outlook remaining significantly below average. Lake Powell will probably end the current water year at just 44 percent of capacity.

The past decade has seen significant variability in precipitation totals, with near record runoff in 2011, followed by two of the driest years on record.