“Grand Canyon advocates lament lack of environmental flows this spring”
Excessive-flow experiment on the Grand Canyon goals to assist Colorado River
Water is launched from Glen Canyon Dam by bypass tubes, April 24, 2023, throughout a high-flow experiment. The flood will assist transfer sand and sediment down the Colorado River the way in which the river’s pure flows did earlier than development of Glen Canyon Dam.
Mark Henle, The Republic
- Federal officers have confirmed that they won’t flood the Grand Canyon this spring, citing ongoing work on Glen Canyon Dam and within the Colorado River downstream.
- Colorado River advocates say failing to flood the Canyon will harm efforts to revive seashores and protect the atmosphere beneath Glen Canyon Dam.
- Some river advocates say the federal government’s determination might run afoul of the Grand Canyon Safety Act, which requires the feds to protect ecological and leisure features of the Canyon.
Federal officers have rejected a plan to launch floodwaters from Lake Powell to revive Grand Canyon seashores this spring, irritating river advocates who query the federal government’s dedication to defending the canyon’s atmosphere.
Glen Canyon Dam has impounded the Colorado River close to the Arizona-Utah line since 1963, and with it the annual load of sand that pure snowmelt floods beforehand churned up onto seashores and sandbars within the Grand Canyon annually. The U.S. Bureau of Reclamation, working by a collaborative adaptive administration program to take advantage of what sand a smaller tributary nonetheless deposits beneath the dam, has flooded the canyon by opening the dam’s bypass tubes 12 occasions since 1996.
With repeated selections to not open the floodgates even when the sand is accessible, some are questioning whether or not the Glen Canyon Dam Adaptive Administration Program is preserving Grand Canyon’s ecology and recreation as required beneath the Grand Canyon Safety Act of 1992.
“We are failing,” mentioned Ben Reeder, a Utah-based river information who represents the Grand Canyon River Guides on a technical work group that considers administration choices for the Reclamation Bureau.
“Deeply disappointed,” mentioned Larry Stevens, a canyon ecologist who represents Wild Arizona and the Grand Canyon Wildlands Council on the work group.
Reeder and Stevens have been amongst advocates and state company officers who reluctantly agreed to forego a flood final fall in favor of saving the sand for a extra naturally timed springtime flood. Occasions over the winter would intervene with that plan.
‘In search of any excuse’ to not stage a flood
Reclamation officers mentioned in April that they’d suggest that new Inside Secretary Doug Burgum not authorize the flood as a result of a Nationwide Park Service contractor was excavating in a slough downstream of the dam to disrupt its use as a spawning mattress by non-native fish, together with smallmouth bass. Work on relining the bypass tubes to guard their metal pipes additionally interfered.
On Thursday, Could 22, the company introduced that the choice in opposition to flooding was last.
Those that had anticipated a rejuvenating flood mentioned they respect the necessity to defend native fish from voracious predators just like the bass, however that there’s too usually some motive or one other to reject bypassing the dam’s hydropower generators to ship water downstream, a price to the dam’s energy prospects across the West. In 2021, as an example, the federal government declined to flood the canyon to prop up Lake Powell’s water degree.
“It just seems like looking for any excuse not to do one,” Reeder mentioned. The default seems to be in opposition to flooding in any given yr, he mentioned, maybe as a result of the group that finally recommends for or in opposition to doesn’t embrace environmentalists or recreationalists.
“It really kind of bothers me, honestly, that we talk about the Grand Canyon in these economic terms as if it’s there for human consumption,” Reeder mentioned.
Recent off a Could river journey, Reeder mentioned seaside erosion is obvious all through the canyon. Rains from final yr’s monsoon significantly battered one in every of his most popular tenting seashores, at Stone Creek.
“We have a sand-starved system,” he mentioned.
Environmentalists favor a spring flood over fall, as a result of it finest mimics the river’s pure rhythm. Angler advocates additionally favor spring, because it comes at a time that may higher assist a tailwater rainbow trout fishery, which has suffered in recent times as low water in Lake Powell led to a warming river. Greater than any flood, the trout want extra water within the reservoir, pushing the nice and cozy floor farther from the dam intakes, mentioned Jim Strogen, who represents Trout Limitless within the adaptive administration discussions.
“A deeper, colder lake is the best thing for that fishery,” he mentioned.
Energy suppliers say floods value them cash
The floods value maybe $1 million or $2 million in misplaced hydroelectric manufacturing, based on Leslie James, who represents largely rural and tribal energy shoppers in this system as govt director of the Colorado River Energy Distributors Association. Final yr, when there was no main flood however the dam managers frequently pulsed chilly water by the bypass tubes to maintain the river inhospitable to bass spawning, the company mentioned the price in misplaced energy manufacturing was $19 million.
The losses deplete a fund that pays for dam upkeep and environmental packages, James famous, and drawing extra from that fund this yr might trigger delays in upkeep.
“We weren’t asked our views on (a spring flood), she said, “but if asked we would say that we always have concerns about bypassing hydropower generation.”
James mentioned a repeat of final summer season’s cool releases to fight bass appears pointless, as bass thus far are usually restricted to the 15 miles beneath the dam and will not be displaying up dozens of miles downstream on the confluence with the Little Colorado River, a haven for native humpback chubs. Reclamation officers mentioned they are going to determine in June whether or not to pulse chilly water by the canyon this summer season.
The company reported that final yr’s cool flows appeared to have labored, stopping any detectable progress in bass numbers by preserving the river largely beneath 16 levels Celsius — the temperature at which bass reproduce efficiently — as far downstream because the Little Colorado. It additionally projected that with out bypass flows this summer season, temperatures within the river possible would rise above 16 levels.
A federal biologist engaged on chub conservation advised The Arizona Republic it will not be stunning if bass attain the Little Colorado by fall and reverse positive factors within the native fish inhabitants that allowed the federal government to downlist the chub from endangered to threatened in 2021.
The floods, achieved with blasts of water that jet throughout the canyon beneath the dam, may give the inaccurate impression that water is misplaced downstream. In actuality, whereas the floods do briefly scale back Lake Powell’s elevation, they don’t hurt irrigators or municipal water suppliers. Lake Mead captures the water on the Grand Canyon’s west finish and shops it for later use in Nevada, Arizona, California and Mexico.
Reclamation officers initially advised members within the adaptive administration collaboration {that a} flood was unlikely in April, when Program Supervisor Invoice Stewart mentioned each try had been made to schedule it. When the teams and businesses had agreed to place off a flood final fall, he mentioned, it had appeared there can be a window in Could when each slough modifications and dam upkeep can be performed. The plan was to flood the canyon for 60 hours, with a peak movement of 40,400 cubic ft per second, in comparison with routine flows in Could starting from 8,000 to 13,382 cfs.
Throughout the transition in presidential administrations, work within the slough was delayed, resulting in heavy gear remaining within the river hall all through the month. Dam upkeep additionally lasted into the timeframe when a flood was envisioned, leaving among the bypass tube capability unavailable.
“We really did make every effort to make this happen,” Stewart advised flood advocates tuning in to April’s digital assembly.
Some members, together with Arizona Recreation and Fish Division biologist David Rogowski, mentioned this system wants to enhance its scheduling.
“We need to be better about planning for the future,” Rogowski mentioned. “We aren’t doing (a spring flood) because of poor planning.”
Stevens agreed, saying Reclamation ought to incorporate deliberate floods into its routine upkeep schedule.
A river scientist who beforehand led the U.S. Geological Survey’s Grand Canyon analysis group mentioned the Reclamation Bureau’s persevering with development of skipping alternatives to flood the canyon jeopardizes Grand Canyon Nationwide Park’s sandbars — a function he mentioned is as very important to the park’s pure atmosphere because the sandstone partitions looming above the river.
“It is disturbing that sand bars always come out second,” mentioned Jack Schmidt, a Utah State College researcher and former head of the Grand Canyon Monitoring and Research Center. “It’s removing an entire landscape element.”
Brandon Loomis covers environmental and local weather points for The Arizona Republic and azcentral.com. Attain him at [email protected].
Environmental protection on azcentral.com and in The Arizona Republic is supported by a grant from the Nina Mason Pulliam Charitable Belief.
Comply with The Republic environmental reporting group at environment.azcentral.com and @azcenvironment on Facebook and Instagram.
Have any questions or want help? Contact us here. For extra insights, go to our website.
Learn More…
