The 2012 water year is definitely one that will be remembered for quite some time. Coming on the heels of one of the wettest and snowiest years in recent memory it began with great expectations and with well above average precipitation in October and significant early season snow storms across the state. Unfortunately hopes were thwarted by a very dry December which left our first snow surveys of the year measuring a below average snowpack. From that point, with the exception of some decent snow accumulation in February, the weather managed to conjure up some painful memories of the 2002 drought. In the end this season saw the lowest statewide snowpack accumulation since 2002 and in some basins, this year became the new minimum on record. This spring the entire state has experienced persistent warm and dry weather patterns contributing to dry soils and the early melt of an already anemic snowpack. The only part of the equation separating this year from conditions in 2002 is reservoir storage. Across the state storage volumes remain very close to average thanks to the abundant snowfall and runoff from the 2011 winter.
May ended up being another dry and warm month across Colorado. The continuation of this abnormally warm weather caused the snowpack to continue to melt out at a nearly uninterrupted pace. By June 1, the snowpack was nearly nonexistent in all of Colorado’s major basins with only 4 out of the 92 SNOTEL sites used in this report, measuring any snow. The statewide snowpack as of June 1 was a negligible 2 percent of average, and 1 percent of last year’s report on this date. Basin by basin only the Colorado, South Platte, Arkansas and combined Yampa, White and North Platte basins had any snow remaining and only at the higher elevations in the basins. Most SNOTEL sites were completely melted out about a month earlier than normal. The warm weather this spring in combination with dry winds and dry soils really decimated what little snowpack we had received. These conditions also result in a fair amount of sublimation which will likely have an impact on streamflow volumes.
Precipitation at Colorado’s SNOTEL sites was well below average this May. Six out of the last seven months have recorded below average precipitation across the state. Statewide totals for May were just 42 percent of average which dropped the water year to date precipitation to 71 percent of average and 59 percent of last year’s totals. The combined San Miguel, Dolores, Animas and San Juan basin received precipitation that was only 14 percent of average for the month and the Gunnison basin was also very dry at just 23 percent of average. The South Platte basin fared somewhat better with monthly totals at 62 percent of average. Water year totals range from a high of 85 percent of average in the Upper Rio Grande basin to 66 percent of average in the Colorado basin.
Reservoir storage in the state is slightly below average. In an average year the state’s reservoirs store 3786 kilo acre feet (KAF) of water at this time of year. This year storage levels are at 3716 KAF, which equates to 98 percent of average. Since May 1 storage volumes statewide have declined by 24 KAF. Typically storage volumes increase during May but water managers filled their reservoirs early due to low streamflow predictions and demand has likely increased with above normal temperatures. As of June 1 the Arkansas and Upper Rio Grande reported the lowest storage volumes in the state at 78 and 57 percent of average respectively. All other major basins in the state are reporting near or above average storage. The Gunnison River basin’s reservoirs are storing 823 KAF which is 103 percent of average. The Upper Colorado basin is storing 905 KAF which is 113 percent of average. The South Platte basin is storing 930 KAF which is 95 percent of average. The combine San Miguel, Animas, Dolores and San Juan basins are storing 526 KAF which is 106 percent of average. And the Yampa basin is storing 34 KAF in Stagecoach reservoir which is 113 percent of average; Yamcolo reservoir was not included in this report due to a broken gauge.
Another dry month in May brought additional decreases to the streamflow forecasts across western Colorado. As a general rule, forecasts for the western basins range from about 25 to 50 percent of average. In the Upper Rio Grande, Arkansas, and South Platte basins seasonal predictions improved by a couple of percentage points for most forecasts due to higher than expected observed flows so far this spring. These basins can expect volumes of 20 to 60 percent of average. The lowest forecasts, as a percent of average, are in the headwaters of the Gunnison River, where the forecasted flow for the Tomichi Creek tributary is just 7 percent of average. The state’s best outlook, while still quite dismal, is for the Upper Rio Grande basin as a whole. Streams in this basin are expected to run at 40 to 60 percent of average from April to September. In summary, across the state, early snowmelt has translated to earlier than normal peak flows, which will likely be followed by an earlier than normal return to base flows in mid-summer.
From 9News.com (Robert Garrison):
This year’s light snow pack has prompted north metro water suppliers to ask residents to conserve. Cities from Arvada to Broomfield and Thornton, as well as South Adams County, are suggesting homeowners to water their lawns no more than two times a week. If there is extreme heat, they suggest watering your lawn three times a week–and if it rains even less. Do not water between 10 a.m. and 6 p.m. And know your water use so you can track it.
From The Denver Post (Kirk Mitchell):
“It’s very conducive to large wildfires spreading,” Skordahl said. “You are talking about drought conditions across the state. The soil is dry. The vegetation is dry. Precipitation is below normal and its windy.”
According to the June 1 Colorado Basin Outlook report released today, the snowpack in Colorado is 2 percent of average for the date, and 1 percent of the snowpack measured on June 1, 2011. Because of abnormally high snowpacks last year, reservoirs are not yet in trouble, still measuring at about 98 percent of average, she said. Still, water managers across the state are concerned that water demand from farms and municipalities will quickly drop reservoir levels across the state, she said.
Only four of 92 snowpack measuring spots across Colorado had any measurable amounts of snow at all and then only in the higher elevations, according to the June snowpack report. But Skordahl said its been so hot and dry the last several months that she was surprised there was measurable snow at any of the locations…
“A wet summer could turn things around,” she said.
The Weld County Commissioners — after declaring a drought emergency on Monday — are asking for a powwow with Governor Hickenlooper over pumping groundwater along the South Platte River alluvial aquifer. Here’s a report from Jack Minor writing for the Greeley Gazette. From the article:
On June 11, 2012, the Commissioners unanimously passed a resolution declaring a disaster emergency for Weld County and asked Governor Hickenlooper to order the pumping of some of the 8,400 restricted irrigation wells for 30 days to provide relief from emergency conditions. “This is a situation that requires immediate attention,” said Commissioner Chairman Sean Conway. “If water isn’t made available to the farmers in Weld County within the next couple of weeks, crops will fail and the economic impact will be felt throughout the state.”[...]
In the request for a meeting, the letter notes that the action is necessary to avoid the current disaster from getting worse to the county, which is the state’s largest agricultural county, producing over $1.4 billion to the state economy. As the Gazette previously reported, area farmers have testified on multiple occasions that the situation is desperate…
“We are like the tsunami warning system. You may not hear it coming, but we farmers are sounding the warning to you,” he said. “The good news is this disaster, which is both natural and man-made with the turning off of the wells can be avoided and it won’t cost the taxpayers one dime. All we have to do is flip a switch.”
The next CWCB Water Availability Task Force meeting is next Wednesday. I plan to live-tweet the meeting.
From the Associated Press via the The Denver Post:
The town of Frisco is asking residents to voluntarily conserve water.
The town is preparing for possible drought conditions following a dry winter and spring with below-average snowpack. Town officials said Monday they are asking people to voluntarily limit how much they water their lawns and plants.