May 1 San Juan snowpack update

Snow levels have presumably peaked in the San Juan Mountains and, as expected, they look pretty darned healthy. That said, it’s not quite the biggest snow year on the books. How 2019 ranks depends on which SNOTEL station you’re looking at.

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Check out the graphs (and one table) in the slideshow above and you’ll see that as of May 1, this year’s snow levels were the second highest at Red Mountain Pass and Columbus Basin, fourth highest at the lower elevation Cascade station, and fifth at Molas Lake (which seems off to me).

But whether it was a record year or not, it’s clear that it has been — and continues to be — a good year for water supplies and river flows in the whole region. At every station the snowpack remains far above average, and three to four times what it was at this time last year. Also, one only needs to look at all the snow slide debris in the high country to determine that it was a historic avalanche cycle.

The Riley Boy slide came from the left side of the picture, went down into a valley, then back up onto the highway, depositing a lot of snow and some pretty sizable trees. 

But that was past. What about the near future? How high will the Animas River get this year?

It’s already hit 3,000 cubic feet per second in Durango, which is plenty of flow for some good kayaking and rafting (albeit a bit chilly). And it’s fair to bet that it will top 5,000 cfs before the runoff is over. But whether it will shoot up past 8,000 cfs as it did in 2005 (which saw a smaller snowpack at most stations in the watershed) or not is anyone’s guess.

Just because the snowpack is bigger than 2005 doesn’t mean the runoff will hit a bigger peak. A cool spring will result in a slower melt, and that will mean a higher average flow and a longer rafting season, but not necessarily a bigger peak.

Either way, the reservoirs are likely to get a bit of a boost, and the smaller ones will likely get topped off. As for Lake Powell rising back up to its former glory? Don’t get your hopes up.