GUNNISON, Colo. (CBS4) – Next month, the Bureau of Reclamation will begin a drawdown of Blue Mesa Reservoir near Gunnison. The Blue Mesa is already low because of the poor winter snowpack on the Western Slope.
But it’s in much better shape than Lake Powell in Utah and Arizona. The Bureau says since its pre-drought high in September 1999 at 95% capacity, Lake Powell has dropped more than 145 vertical feet. It’s down 16 million acre feet of water. Fearing there’s not enough to generate electricity at its hydro facilities the bureau is seeking water from upstream.
“These enormous reservoirs, Lake Powell and Lake Mead are now going to be below 30% full by mid next year,” said Brad Udall, senior water and climate research scientist and scholar at CSU.
The drought that began 22 years ago has shorted reservoirs throughout the West. The 99-year-old Colorado River Compact, signed by Western states in 1922 has resulted in nearly a century of water sharing from upper basin states like Colorado, Wyoming and New Mexico to lower basin states. But conditions have changed through the years notes Udall.
“In the 20th Century, we would get a lot more really wet years to help refill those reservoirs… Now we’re getting about half of those wet years that we previously got.”
When the compact was signed there was no significant scientific consensus that there was climate change occurring. And with climate change says Udall, there’s more evaporation.
“The atmosphere actually wants to hold more moisture so it’s a sponge, if you will, and wants to suck up more from the ground.”
But drawing more from upstream has reverse ripples.
“People are still having a hard time in the water community grasping just how bad this might be.”
It’s not great news on the Blue Mesa.
“Now we’re already finding ourselves back in this hole, but the concerning thing is usually we’re not this far down especially going into the fall. Especially before the salmon have run,” said Robby Richardson, owner and fishing guide with Sportfish Colorado that runs guides on the Blue Mesa.
As the water drops more in Blue Mesa Reservoir starting August, there will be more closures of boat ramps, marina slips, and other related facilities throughout August. The National Park Service intends to maintain recreation opportunities as long as possible, said the bureau in a statement.
“Docks will need to be moved, fuel lines disconnected, and floating restrooms and boat waste pumping station removed.”
The Blue Mesa will fall an additional 8 feet in the drawdown.
The Blue Mesa is a broodstock lake to provide salmon eggs for the state’s iconic kokanee freshwater salmon.
“When the water’s lower we have higher water temperatures, which pushes the fish deeper earlier in the year and the deeper water has less oxygenation,” said Richardson. “So sometimes they get pinched in this part of the lake where there isn’t much oxygen.”
The salmon run a marathoner’s distance upstream out of the reservoir to spawn. This year they will have to travel additional miles because the river is longer.
“The water arrangements from many years ago are definitely are complicated and sometimes hard to understand for the people who live where the source comes from,” said Richardson.
Although believing it’s just part of the deal, “Everybody’s got to give where they can. And hopefully we get some big snowpacks in the near future.”
“The real story here though is its going to prop up Lake Powell all of three feet,” said Udall, noting it was the second worst runoff year for the lake since it was first filled in 1964. More bad runoff he believes and there will be more drawdowns.
He wonders whether, “This is actually just a test release and next year if we have another bad year, then there will be a push to release not what we’re doing this year but lots and lots or more water.”
But that’s subject to the drought. If that continues there might be some new conversations about water sharing.
“One more bad year and ‘Katie- bar the door.’ I mean we’re going to have some very hard discussions about how we’re using the water and where it’s going.”