A reprieve for Powell?: The reservoir is at its lowest level since filling up — @Land_Desk #LakePowell #ColoradoRiver #COriver #aridification

Click the link to read the article on the Land Desk website (Jonathan P. Thompson):

The calamitous headlines have come fast and furious: Lake Powell’s water levels reach record low. The new low-water mark, the stories said, is emblematic of the Colorado River crisis and the dreaded dead pool — when Lake Powell gets so scraggly that its water can’t even make it through Glen Canyon Dam — is imminent.

I suggest taking this news with a grain of salt.

It’s true that the reservoir hasn’t been this low since 1968, five years after the Colorado River began backing up behind Glen Canyon Dam. It’s also true that the river on which some 40 million people depend is caught in what appears to be an irreversible decline. Dead pool is inevitable. But it’s not happening this year, because once that massive snowpack upstream from the reservoir starts melting, Lake Powell’s going to get a bit of a reprieve.

In fact, Lake Powell’s record low is actually a good sign — if looked at from a certain angle — because it indicates that water managers are confident enough in this year’s snowpack to release a bit more water from Lake Powell than they otherwise would. That has helped Lake Mead recover, slightly, with water levels climbing five feet since December.

So far 2023’s snowpack levels are tracking identically to snowy 2011’s on this date. But current trends will have to continue for two more months in order for this year to match the bounty of 2011. Source: USDA NRCS.

And the snowpack is looking good. Very good. As of Feb. 28, snow levels in the Upper Colorado River Basin were well above average and tracking similarly to 2011, one of the most bountiful water years of the last two decades. That spring and summer saw rivers swelling up, overflowing their banks, and giving river runners a good — yet dangerous — time. Lake Powell’s level climbed 45 feet that year, in spite of larger than average releases from the dam.

Note that this forecast is from Feb. 3. The snowpack has continued to grow, substantially, since then, meaning the forecasts are somewhat out of date. So far the snowpack is comparable to 2011, when 16.4 million acre feet ran into Lake Powell. Contrast that with 2021, when just 4 maf ran down the Upper Colorado River. Source: USBR.

It’s certainly too early to count on a repeat of the 2011 Colorado River runoff. Snowfall trends could flip. Early springtime temperatures could soar, as they did in 2021, which not only speeds up the runoff but also diminishes it by increasing evaporation. The parched ground could suck up some of the snowmelt, taking it away from the streams.

Yet there is still plenty of reason to be optimistic. Here’s one of them:

The Upper Dolores River watershed in southwestern Colorado, which has been especially hard hit by aridification and overallocation over the last couple decades, currently has 37% more snow than it typically does in early April, when snowpack normally peaks. The snowpack hasn’t been this good since 1993. That means if it stopped snowing now, there’d still be a healthy runoff into McPhee Reservoir, which would mean farmers would get their full share of water and the Lower Dolores might actually get enough water to be called a river.

And yet, aridification is not over. And even if snowfall trends do continue, officials must not backslide on efforts to cut water consumption. Nature has granted a reprieve — but only a temporary one.

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