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Snowmelt watch: How Colorado reservoirs are already seeing a boost

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Posted at 12:44 PM, Jun 13, 2019
and last updated 2019-06-13 14:46:10-04

DENVER – We're still seeing ridiculously high snowpack percentages across Colorado – 751% above normal statewide, including 1,462% in the San Juan Mountains.

All that snow, as temperatures continue to rise, has to go somewhere and has already led to some isolated, minor flooding and stronger currents along state rivers.

But the melting snowpack should be a good thing for Colorado reservoirs, which have sat well below capacity. We're already seeing that positive effect in southwest Colorado.

From April to May, the overall capacity of reservoirs in the San Miguel, Dolores, Animas and San Juan River Basin jumped from 58% to 77% capacity, according to the National Resources Conservation Service's monthly reports.

Further north, through the Colorado and Yampa & White river basins, reservoir capacities increased from 58% to 67% and from 86% to 92%, respectively. While those jumps weren't as large, the Colorado and Yampa & White river basins' reservoir capacities are 117% and 115% above last year's average, respectively.

As a whole, we still have a ways to go: Statewide reservoir capacity still sat at 57% by the end of May, up from 53% in April.

But the snowmelt boost "couldn't have come at a better time," Greg Smith, a hydrologist with the Colorado Basin River Forecast Center, told the Associated Press. "There's a big sense of relief this year that we've kind of rebounded."

The forecast center's conditions map shows the good news – plenty of light and dark blues throughout western Colorado, indicating above-average water supply forecasts at reservoirs.

Again, a key impact can be seen in southwest Colorado, where seven reservoirs have a forecasted water supply of 130% or above. The McPhee Reservoir in Dolores, the Hesperus Reservoir in La Plata and the Vallecito Reservoir in Los Pinos were all forecasted at more than 150% of average, as of this week.

Nearby, the National Weather Service has issued a flood warning, with the Rio Grande near Del Norte forecasted to reach a minor flood stage. Surrounding areas are also under a flood watch. But with some minor flooding becoming a risk, the snow runoff is also helping the reservoir levels.