Rapid Musings: The Return of Gypsum in Cataract Canyon
The Re-Emerging River Above Lake Powell
Most guides have different stretches of river burned into our minds. We know what comes around each bend. We know exactly where we want to camp based on river flows and time of the year. We can close our eyes and have an exact picture of each rapid at each different flow in our mind, knowing what the water is doing, what obstacles there are and how to maneuver around them. Typically, the rapids that we see don’t change (aside from looking differently at different flows).
Differences in a rapid are normally only seen after some sort of very rare big event, like a large flash flood or a major rockfall. This is why Cataract Canyon is such an amazing and unique stretch of river: the rapids in the lower reaches of the canyon are changing somewhat regularly, mainly due to the dropping levels of Lake Powell.
Buried By Sediment
Water began piling up behind Glen Canyon Dam in 1963, capturing the Colorado River behind the 710 foot concrete monstrosity to create Lake Powell. The lake was filled completely in the 1980s, inundating 25 miles of Cataract Canyon’s 41 mile river corridor. Those 25 miles of river contained about thirty rapids (some of which were rumored to be as exciting as any other rapids found on the Colorado Plateau), extraordinary side canyons with incredible hiking opportunities, and of course beautiful canyon scenery.
As the old river sat submerged under the waters of a full Lake Powell in the 1980s and 1990s, all of the sediment carried by the Colorado River hit the lake. Unable to flow downstream, the sediment had nowhere to go but down to the bottom of the lake, filling in the Colorado River’s original channel. When lake levels began to drop in 2002, the Colorado River was forced to carve its way back down through all the sediment deposited by Lake Powell, and the lower reaches of Cataract Canyon began to transition from lake back to river. Mile by mile, this process began to uncover rapids that were buried under the muck of the lake, and those rapids that were once lost started to return.
Changes at Gypsum Canyon
The lower reaches of Cataract Canyon are filled with some of the most glorious side canyons that I’ve ever seen from the river. One of the largest of these side canyons is Gypsum, draining an area of about 120 square miles. The first time I rowed a boat through Cataract Canyon in 2016, the river flowing past Gypsum barely resembled a river at all. Cliffs of silt fifteen feet tall towered up from the river banks, a reminder that the exact place through which we were floating was once drowned twenty feet below the bottom of the lake. There was almost no detectable current, the water completely flat and practically motionless. All of our boats had been strapped together further upstream, and we were already motoring our way off of the lake and out of Cataract Canyon. The river next to Gypsum appeared unchanged for the next four seasons that I spent rowing past there.
Last year, the changes that had been happening under the water near Gypsum since the levels of Lake Powell began to drop started to become visible to us. The area that once resembled a lake finally began to look like a river again. Early on in the season, we noticed that, although the water still looked basically flat, we had current flowing well past Gypsum. As the season progressed, small waves appeared on the surface of the water. Passing this side canyon started to feel a little bit sketchy, having to pull the motor up to avoid whatever rocks or silt was under the surface creating the small features in the river. It didn’t take long for us to decide it would be best to hold off on motoring until we were below Gypsum, so for the rest of the year we rowed our boats until we were below the riffle. That was when I really started to feel like the river was coming back.
It’s incredible to float through the lower reaches of Cataract Canyon and see the changes that are happening. Though the fact that these rapids are returning represents a grim reality about the water supply in the West, I can’t help but to feel sincere excitement about the returning rapids. We are watching a drowned river come back to life. And I feel beyond lucky every time I row this reborn section of water.
Photos: Gypsum Canyon Rapid area – Returning Rapids, Pete Lefebvre, Glen Canyon Dam – Wikimedia Commons, Side canyons – Whit Richardson, Gypsum Canyon Rapid – Returning Rapids, Mike DeHoff