Desert Notebook

Will there be enough water?

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It’s snowpack forecast season, and trained eyes find the published reports in the Tribune to gauge the estimated runoff potential in area drainages.

Agricultural fortunes are, of course, a primary focus. The first box that farmers want to check is the projection for healthy water availability for the irrigation season ahead.

Recreationists also pay heed to the water flow predictions. The Shoshone River drainage, the Bighorn River drainage and the Clark’s Fork River drainage get the closest scrutiny in these parts.

There’s a high stakes case of the same exercise going on in this country’s Southwest by those dependent on water from two key U.S. Bureau of Reclamation-managed reservoirs on the Colorado River — Lake Powell which straddles the Arizona-Utah border and Lake Mead,  which lies in Nevada and Arizona.

And who’s paying attention to this urgent watch? Maybe 50 million people with diverse thirsts. Real consequences are on the line.

We were met with a surface picture of water shortage as we drove into the Lake Powell area and Glen Canyon Dam near Page, Arizona, on our trip to the Tucson area on the first of February. The leached white “bathtub ring” on the canyon walls of Lake Powell behind the dam tells it all.

Indicating the previous high water mark of Lake Powell, we were told at the visitor center that the band of leached rock was 123 feet deep at the dam. Or plainly said, the level of Lake Powell has dropped 123 feet.

In the snow-starved 2018 runoff year, the lake came up only 4 feet.  The previous year (2017), the lake recovered 44 feet with snowmelt. Reservoir watchers are anxiously awaiting the 2019 runoff.

The picture at Lake Mead behind the Hoover Dam, only 25 miles from the Las Vegas strip, is even more dire. The last time Lake Mead, downstream on the Colorado below the Grand Canyon, was full to its capacity of 26 million acre-feet of water was in 1983.

After the last 19 years of drought and overuse, Lake Mead is at only 40 percent of capacity with roughly 12 million acre feet of held water in 2019.

The Bureau of Reclamation has stepped into the picture, requesting from the three states which take water out of Lake Mead — Arizona, California and Nevada — Drought Contingency Plans for how they would reduce their withdrawals if it came to it to prevent Lake Mead from falling to critically low levels.

The point which would trigger the Drought Contingency Plans is said to be when and if the elevation of Lake Mead should fall to 1,075 feet. The lake elevation has been as low as 1,081 feet in 2010.

All three states met the bureau’s Jan. 31 deadline to submit their plans. In Arizona, there were sometimes tense negotiations that can produce winners and losers. Final approval may go all the way to Congress.

Wyoming has a part to play in the drama. Wyoming, Utah and Colorado are the principal Upper Colorado River Basin states which contribute snowmelt to Lake Powell (and ultimately to Lake Mead). New Mexico bridges the upper basin and the lower basin areas of the Colorado River drainage.

The Green River Basin of Wyoming is the source of Colorado River runoff contribution from this state.

Snowmelt and water levels can be determined and numbers crunched. Plans can be written and agreed to. They were, because they were mandated.

There is a harder part. Some questions will need to be confronted and reflected upon thoughtfully. They aren’t easily dealt with on deadline.

This is not to pick on agriculture, but an Arizona legislator who voted against his state’s Drought Contingency Plan, did so do with a muse: “Maybe we shouldn’t be growing high water-consuming crops like cotton and pecans in the desert.”

Desert Notebook

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