NRCS: The first Water Supply Outlook for 2015 is hot off the presses


Click here to read the report. Here’s an excerpt:

On January 1, at 99 percent of normal, Colorado’s snowpack is at exactly the same levels seen in 2001 and close to the totals recorded in 1995 and 2014. It is a positive sign that these years, which closely compare to this year, all experienced snowpack peaks at or above normal. While this information cannot be used as a forecast, it is often useful to examine what occurred in similar years. The snowpack in the Arkansas River basin is currently ranked 11th of the 35 year period of record. Simultaneously the Colorado River basin is currently ranked 8th of 34 years in the period of record. Unfortunately the southern basins such as the Upper Rio Grande and the San Miguel, Dolores, Animas & San Juan, the watersheds with the greatest needs for above normal snowpack’s to make up for recent deficits, did not see the same snowpack gains as the central basins. The Upper Rio Grande watershed presently has the 7th lowest snowpack in its 29 year period of record. Looking back to the north, the Laramie River basin, at 88 percent of normal, has the lowest snowpack of the sub-watersheds in the Colorado, South and North Platte River basins yet all other sub-watersheds have snowpack’s at 95 percent of normal and above. Statewide snowpack totals range from 47 percent of normal in the Alamosa Creek drainage to 146 percent in the Upper Arkansas basin.

Here’s the first snowpack news release from the Natural Resources Conservation Service (Mage Skordahl) for 2015:

As we began the new water year it looked like summer might never end given the unseasonably warm temperatures and nearly nonexistent precipitation throughout October. Thankfully November brought cooler temperatures and snow to the mountains across the state, but then the moisture dried up before Thanksgiving and the state experienced an unusual lack of moisture for over two weeks. Skiers and winter enthusiasts had no reason to be concerned however as a few big storm systems brought significant snow accumulation just in time for the Christmas holiday and boosted the statewide snowpack totals to 99 percent of median as of January 1. According to Brian Domonkos, Snow Survey Supervisor with the NRCS, “The statewide snowpack is right where it needs to be for this time of year. It’s difficult to make up an early season deficit in snow accumulation, so being right at normal is a great place to be.”

Unfortunately not all of the major basins in Colorado are reporting normal snowpack conditions. According to January 1 snow surveys conducted statewide, the Upper Rio Grande and San Juan, Animas, Dolores, & San Miguel basins are reporting totals at just 71 and 75 percent of median respectively. This is not great news for these areas which have not recorded a normal seasonal snowpack since 2010. If these basins don’t receive increased precipitation over the next few months, they may be looking at their fifth consecutive year of below normal snowpack and seasonal streamflow runoff. The other major basins are faring much better so far this season with snowpack totals for January 1 ranging from 114 percent of median in the Colorado basin to 99 percent of median in the Gunnison basin. East of the Continental Divide the South Platte basin is at 112 percent of median.

Statewide reservoir storage is in good shape; end of December storage totals were at 103 percent of average. The distribution across the state varies however, with the southern basins all reporting below average storage and the northern basins all reporting above average storage. The Upper Rio Grande basin has the lowest percentage at just 67 percent of average and 19 percent of capacity. The South Platte basin has the highest storage totals, which are at 124 percent of average and 82 percent of capacity.

The January 1 streamflow forecasts follow the trends in snow accumulation and precipitation received this season across the state. Predictions for the northern streams call for above normal flows this spring and summer while outlooks for the southern streams are below normal.

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