Flash flooding causes major damage to the Grand Canyon's critical water pipeline

WASHINGTON (AP) — The sole pipeline that supplies water for millions of Grand Canyon visitors was badly damaged by weekend flash flooding, setting up a tricky repair scenario and upending a yearslong construction project to upgrade the line laid over terrain so rugged helicopters are often required to make basic fixes.

Park officials said roughly 40% of the pipeline was damaged or destroyed. The long-term implications of the damage to the park's infrastructure, visitors and year-round residents weren't immediately clear. The 12.5-mile (20-kilometer) long Transcanyon Waterline has endured dozens of breaks in recent years. A more than $200 million repair and replacement project was well underway when the floods hit.

Caused by heavy rain, the floods killed at least two people, left more than a dozen others missing or unaccounted for and required the evacuation of more than 60 people. Officials said significant water reductions are needed — short showers, turning off the tap while brushing teeth and flushing toilets selectively to to protect the limited stored water on the South Rim, where most visitors go.

The pipeline, which was finished in the 1970s, has broken more than 85 times since 2010. It moves water from one side of the canyon, down to its base, across a bridge and back up the other side of the rough landscape. Any effort to fix a break from rock falls or flash floods is time-consuming, precarious and costly, so addressing the latest damage will be complicated.

The pipeline upgrade project, which began in 2023, took more than a decade to design, consider and fund. It involves moving the point where water would flow into the pipeline, installing helicopter pads, building water treatment facilities and replacing several miles of pipeline.

Basic decisions were complicated. For example, the original pipe was aluminum, which is lighter and easier to move into the steep canyon but is susceptible to breaking. Engineers picked a flex-steel material to balance weight with durability.

Even routine pipeline breaks force water restrictions. In 2016, a hotel on the canyon's rim that offers luxury dining and boasts about its history hosting presidents was forced to reduce dishwashing and use paper plates and plastic utensils.

The park had water conservation measure in place even before the latest bout of flooding and damage.

The flooding has forced parts of the park to close and additional flooding was possible Monday, according to the National Park Service.

“Consider changing your plans if you were going to hike, boat, or paddleboard to a slot canyon or normally dry wash. If you do still decide to recreate, check in at a nearby visitor center or ranger station,” a notice on the park website said.

Officials said previously that the repair and replacement project would ensure that the park will be able to meet its water supply needs for the next 50 years or more. The park had roughly 4.4 million visitors last year.

When the original pipeline was nearing completion in the 1960s, more than a foot (0.3 meters) of rain fell, flooding the inner canyon. That rare historic flood caused 40% of the project to be destroyed, officials said.

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People stand at the rim of the Grand Canyon as rain moves into the canyon, Monday, Aug. 31, 2026, in Grand Canyon National Park, Ariz. (AP Photo/John Locher)

Tourists check out of the El Tovar Hotel as lodging along the rim of the canyon was shut down due to flooding, Monday, Aug. 31, 2026 at Grand Canyon National Park, Ariz. (AP Photo/Josh Biggs)

Bright Angel Canyon, middle left, the scene of flash floods, meets with the Colorado River in the Grand Canyon, Monday, Aug. 31, 2026, at Grand Canyon National Park, Ariz. (AP Photo/John Locher)

Buildings are seen in a flood damaged Bright Angel Canyon the Grand Canyon, Monday, Aug. 31, 2026, in Grand Canyon National Park, Ariz. (AP Photo/John Locher)

FILE - A section of pipeline that brings water to the South Rim of Grand Canyon National Park is seen below Bright Angel Lodge in Arizona, Aug. 30, 2024. (AP Photo/Ty ONeil, File)

WASHINGTON (AP) — Army Secretary Dan Driscoll is stepping down after 18 months on the job, the White House said Monday, in the latest departure of a top military leader during the Trump administration.

No reason was given for the departure of Driscoll, who is a friend of Vice President JD Vance, but tensions with Defense Secretary Pete Hegseth have been widely reported. It marks the latest in a series of shakeups of the military leadership, with the Army especially seeing major upheaval.

“Secretary Driscoll has been highly effective in advancing President Trump’s agenda to Make America Strong Again at the Department of the Army by providing outstanding leadership during historic military operations, restoring an emphasis on readiness and lethality, assisting with negotiations between Russia and Ukraine, and more," White House spokeswoman Anna Kelly said in a statement.

"The United States Army is more powerful than ever thanks to his work alongside the Commander-in-Chief and Secretary of War,” she added.

A U.S. Army official, who was not authorized to comment publicly and spoke on condition of anonymity, confirmed that Driscoll submitted his resignation. The official did not provide additional details. The Pentagon referred questions to the Army. Driscoll's resignation was reported earlier Monday by The Wall Street Journal.

Hegseth suddenly ousted the service's top uniformed leader, Gen. Randy George, in April, while the Army’s commander in Europe and Africa, Gen. Christopher Donahue, unexpectedly stepped down in June.

Gen. Christopher LaNeve, who has made a meteoric rise under Hegseth, took George's place as the Army’s acting chief of staff. Under LaNeve, the service is pulling the plug on a drone modernization program that Driscoll had heralded. An Army unit based in Europe was building its own drones before LaNeve directed it to end its efforts and return to being a traditional infantry battalion, officials said in August.

Driscoll was a George ally and lamented his departure, along with both Republican and Democratic lawmakers. He told Congress in April that he and his family drove to George's house following his resignation “and we all gave him a hug.”

“That being said, the civilian leadership, the design of our system, is that they get to pick the leaders that they want," Driscoll added.

Driscoll is an Iraq war veteran, tech investor and former adviser to Vance, whom Driscoll met at Yale Law School. When nominating Driscoll in 2024, President Donald Trump called him “a disruptor and change agent.”

As Army secretary, Driscoll was tapped for the unusual role of key negotiator to try to end the war between Russia and Ukraine. He was also a major force behind trying to cut the red tape for military contractors to quickly develop more drones and counter-drone capabilities as warfare rapidly changes around the world.

The Senate confirmed him in February 2025, voting 66-28, following an Armed Services Committee hearing that was largely unconfrontational and focused on how the Army could modernize its systems, improve recruiting and beef up the military industrial base.

Driscoll noted that his father and grandfather served in the Army and he vowed to be a secretary focused on the needs of soldiers. According to the Army, Driscoll served as an armor officer from August 2007 to March 2011, deploying to Iraq from October 2009 to July 2010.

He also ran unsuccessfully in the Republican primary for a North Carolina congressional seat in 2020, getting about 8% of the vote in a crowded field of candidates.

His departure comes after Hegseth ousted several other generals and admirals, including the head of the Navy.

The Pentagon abruptly announced in April that Navy Secretary John Phelan was leaving the job, becoming the first head of a military service to depart during Trump’s second term.

FILE - U.S. Army Secretary Dan Driscoll speaks at the America 250 celebration at Fort Bragg in Fayetteville, N.C., June 10, 2025. (AP Photo/Karl DeBlaker, File)