When was Lake Powell created? Glen Canyon Dam history
Lake Powell began filling on March 13, 1963, when crews closed the last Glen Canyon Dam diversion tunnel. It took 17 years. The dates, and what went under.
Quick answer
Lake Powell started on March 13, 1963. That day crews closed the last diversion tunnel at Glen Canyon Dam, and the Colorado River began backing up behind the concrete. Filling took 17 years, finishing on June 22, 1980. Congress had authorized the dam nearly 7 years before the water came up, on April 11, 1956.
Lake Powell is 63 years old. People who watched the water climb the canyon walls still live in Page, and some of them worked the dam.
| Milestone | Date |
|---|---|
| Colorado River Storage Project Act authorizes the dam | April 11, 1956 |
| First dynamite blast in Glen Canyon | October 15, 1956 |
| Last diversion tunnel closed, Lake Powell begins filling | March 13, 1963 |
| First hydroelectric power generated | September 4, 1964 |
| Lady Bird Johnson dedicates the dam | September 22, 1966 |
| Congress creates Glen Canyon National Recreation Area | October 27, 1972 |
| Initial filling complete | June 22, 1980 |
Every date above comes from the Bureau of Reclamation’s Glen Canyon Unit pages and the National Park Service.
Why was Glen Canyon Dam built?
To bank water upstream. The Colorado River Storage Project Act of April 11, 1956 gave the Upper Basin states — Colorado, Utah, Wyoming and New Mexico — a way to hold their share of the river instead of watching it run past on its way to Hoover Dam. Hydropower revenue paid off the construction. Glen Canyon was the biggest piece of that plan.
The dam stands 710 feet above bedrock and 583 feet above the old riverbed, with a crest 1,560 feet long. Counting the powerplant, 5,370,000 cubic yards of concrete went into the job. The 8 generators are rated at 1,320,000 kilowatts and put out around 5 billion kilowatt hours in an average year. Construction ran 1957 to 1964, and 18 workers died in accidents over those years.
Water started stacking up 6 months before the last concrete went in, and the dam was dedicated and generating electricity long before the lake behind it filled.
What did the lake bury?
Glen Canyon — 186 miles of the Colorado, plus the side canyons that now make up the fingers you anchor in. Archaeologists knew what was coming. Crews from the University of Utah ran the Glen Canyon Project through the construction years, and a 1,635-site tally published in Utah Archaeology in 2000 remains the final count of what they recorded between 1956 and 1963.
Named places went under too. The Music Temple, an alcove Powell’s party named on the 1869 trip, is gone. So are Gregory Natural Bridge, the Hite ferry crossing at the north end, and the river landing at Hole-in-the-Rock, where Mormon pioneers lowered wagons through a notch in the cliff over the winter of 1879 to 1880. The Crossing of the Fathers, where the 1776 Domínguez–Escalante party forded the Colorado, is open water now in Padre Bay.
Plenty of people fought the dam. Sierra Club director David Brower published The Place No One Knew: Glen Canyon on the Colorado in 1963, with Eliot Porter’s photographs of what had been there, and the campaign around it fed the fight that kept dams out of the Grand Canyon later. How much of Cathedral in the Desert sits above the surface in any given year depends on the lake, and lakepowellwaterlevel.com tracks that side of it.
Who was Lake Powell named after?
John Wesley Powell, who ran the Green and Colorado rivers in 1869 with one arm and 4 boats, and gave Glen Canyon its name. He came back in 1871 for a second, better-documented run, and took over the U.S. Geological Survey in 1881. For much of the main channel, his 1869 route is under your hull.
The town at the south end carries a different Powell. Page is named for John C. Page, who ran the Bureau of Reclamation from 1936 to 1943 — a coincidence of surnames that confuses first-timers who assume the lake and the town honor the same man.
Where did the town of Page come from?
The dam built it. According to the City of Page’s own history, the community began in 1957 as a housing camp for workers on Glen Canyon Dam. In 1958 some 24 square miles of Navajo land were exchanged for a larger tract in Utah to give the camp somewhere to sit. It was called Government Camp before the rename. Page incorporated as a city in 1975, 12 years after the tunnels closed.
That is why your trip probably starts there. The nearest airport and the two southern marinas cluster around a town that only exists because of the dam — see how to get to Lake Powell for the drives and flights.
Which pieces of the old canyon can you still reach by boat?
With the canyon floor under water, 4 of them sit within a few hours of a boat ramp, on trips that used to take a river expedition.
| Site | Where | Boat distance |
|---|---|---|
| Defiance House ruin | Forgotten Canyon, near channel marker 106 | ~13 miles from Bullfrog or Halls Crossing |
| Rainbow Bridge | Forbidding Canyon, around the 50-mile markers | ~50 miles from Wahweap |
| Padre Bay / Crossing of the Fathers | Open water around the 16 to 20-mile buoys | ~13 miles from Wahweap |
| Hole-in-the-Rock notch | Head of the Escalante arm | Remote — check conditions first |
Defiance House is the one most boaters can pull off in an afternoon. It’s a cliff dwelling dated to roughly 1250 to 1285 AD, named for the warrior figures painted above it. The Park Service directions are plain: run up Forgotten Canyon until the water runs out, beach the boat, and follow the social trail to the cliff. You’re allowed inside the structures. Leave the pets on the boat, eat back at the water, and keep hands off the rock art and the walls. The walk is a few minutes some years and closer to 2 miles when the lake is low, which is covered in our Lake Powell hikes guide along with the rest of the boat-in trailheads.
Rainbow Bridge became a national monument on May 30, 1910, when President Taft signed the proclamation — 53 years before there was a lake to reach it by. The span is 290 feet tall and 275 feet across, and it is sacred to the Navajo, Hopi, San Juan Southern Paiute, Kaibab Paiute and White Mesa Ute, who ask that visitors stay out from under the arch. Our Rainbow Bridge guide covers the run from Wahweap and the courtesy dock.
Finding the history without a signal
You lose cell service a few miles past the marinas, which is a problem when the thing you’re looking for is a canyon mouth with no sign on it. Forgotten Canyon is 1 of 132 named side canyons on this lake, and the way boaters find it is by channel marker — 106, in that case. Cell coverage on the lake runs out well before you get there.
Download the map at the dock and the markers stay on your screen with no bars. Our offline map carries all 61 mile-marker buoys, the 132 named canyons and 48 sight landmarks, which is enough to run a history day from Bullfrog to Forgotten Canyon and back without guessing at forks. For the marina end of that trip, the Bullfrog guide has the fuel and ramp details, including the 2026 relocation.
Key takeaways
- Lake Powell began filling March 13, 1963, and finished on June 22, 1980 — 17 years.
- Congress authorized Glen Canyon Dam on April 11, 1956; the first blast came that October and 18 workers died building it.
- Under the lake is Glen Canyon, where University of Utah crews recorded 1,635 sites between 1956 and 1963.
- The lake is named for explorer John Wesley Powell, the town of Page for a Reclamation commissioner.
- Defiance House and Rainbow Bridge are the two pre-dam sites most boaters can still walk to.
Frequently asked questions
When was Lake Powell created?
Lake Powell dates to March 13, 1963, which the Bureau of Reclamation logs as the start of storage behind Glen Canyon Dam. Congress had authorized the dam almost 7 years earlier, on April 11, 1956, under the Colorado River Storage Project Act, and the first dynamite went off in the canyon that October. Filling then took another 17 years, wrapping up on June 22, 1980.
How long did Lake Powell take to fill?
About 17 years. The Bureau of Reclamation shut the last diversion tunnel in March 1963 and the reservoir finished its initial filling on June 22, 1980. Runoff during those years ran through wet and dry cycles, so the rise was uneven rather than steady. The dam itself was finished long before the water caught up: concrete placement topped out in 1963 and the powerplant sent out its first electricity in September 1964.
What is underneath Lake Powell?
Glen Canyon, the stretch of the Colorado the dam plugged, along with its side canyons and everything people had left in them. University of Utah crews surveyed ahead of the rising water from 1956 to 1963; a tally published in Utah Archaeology in 2000 put their final count at 1,635 sites. Landmarks went under as well, including Gregory Natural Bridge, the Music Temple alcove and the old Hite ferry crossing.
Who is Lake Powell named after?
John Wesley Powell, the one-armed Civil War veteran who led the 1869 expedition down the Green and Colorado rivers and named Glen Canyon for the grassy glens along it. He later ran the U.S. Geological Survey. The town of Page is named for someone else entirely: John C. Page, Bureau of Reclamation commissioner from 1936 to 1943, whose name replaced the original label on the workers camp, Government Camp.
How many workers died building Glen Canyon Dam?
18. The Bureau of Reclamation records 18 deaths in various accidents over the construction years, on a job that ran from 1957 to 1964 and put a 710-foot concrete arch across the canyon. Concrete placement topped out in September 1963, six months after the tunnel closure that started the lake, and the first generator came online a year after that.
When did Lake Powell become a national recreation area?
Congress created Glen Canyon National Recreation Area on October 27, 1972, 9 years after the water started rising and 6 years after the dam was dedicated. It covers the lake, the Colorado River corridor and the canyon country around both, in Arizona and Utah. Rainbow Bridge was protected much earlier and separately: President William Howard Taft set it aside by proclamation in the spring of 1910, long before Lake Powell existed.
Can you still visit ruins at Lake Powell?
Yes. Defiance House, an Ancestral Puebloan cliff dwelling occupied from about 1250 to 1285 AD, sits up Forgotten Canyon roughly 13 boat miles from Bullfrog or Halls Crossing. The Park Service lets you walk into the structures but asks visitors not to eat there, use the area as a restroom, bring pets, or sit and lean on the walls. Rock art at the site is off limits to hands entirely.
The old canyon has no cell service
Cache the whole lake before you leave the dock — the Navigator app runs the map and the channel markers offline, so Forgotten Canyon and Padre Bay stay easy to find at zero bars.