Hoover Dam facts at a glance
Hoover Dam stands in the Black Canyon of the Colorado River on the border between Nevada and Arizona. It holds back Lake Mead and serves three jobs: flood control, water storage and hydropower. The Bureau of Reclamation operates the dam and the powerplant, while the National Park Service manages recreation on the lake.
The numbers below are for the dam itself. Measurements are in feet and yards, with metric values added. If you want to see the structure up close, read about Hoover Dam tours, which range from the Powerplant Tour to small-group trips from Las Vegas.
Hoover Dam in numbers
Dimensions, concrete and power.
| Measure | Imperial | Metric |
|---|---|---|
| Height, foundation to crest | 726.4 ft | 221.4 m |
| Crest length | 1,244 ft | 379.2 m |
| Concrete in the dam body | 3.25 million yd³ | About 2.485 million m³ |
| Concrete in dam, powerplant and related works | 4.36 million yd³ | About 3.333 million m³ |
| Main turbines | 17 (9 Arizona side, 8 Nevada side) | – |
| Rated capacity incl. 2 station-service units | About 2,080 MW | – |
The total for concrete is sometimes rounded to 4.4 million cubic yards. That figure covers the whole complex, so do not read it as the concrete of the wall alone. The metric values are converted from the original units.
Our pick: see the generators
The small-group half day plans the exhibits and generators, where the numbers on this page become real.
Hand-picked tours, booked through GetYourGuide. Prices are indicative starting prices in US dollars (as of October 2026). Tap a tour for live availability and the current price in your currency.
Tours to the dam and the lake
Guided visits, small-group trips from Las Vegas, helicopter flights and Grand Canyon West combinations, with live prices and availability.
Power: turbines and megawatts
The powerplant has 17 main turbines, 9 in the Arizona wing and 8 in the Nevada wing, plus 2 station-service units. The rated capacity is about 2,080 megawatts including those two units. Historically the plant has delivered up to 2,074 MW, and in 2026 drought has cut generation by about 30 percent. Treat both figures as capacity, not as what the plant produces on the day you visit.
The lake level drives the output. Plans announced in May 2026 include about $52 million for infrastructure and operations, among them replacing up to three turbines so the plant can run at lower lake levels.
Lake Mead: level and capacity
Lake Mead formed behind the dam. At a water level of 1,221.4 feet its capacity was 28,945,000 acre-feet, about 35.7 cubic kilometers. That is a historical figure for a full lake, not the water in the lake today. A lake level is also not the same as the stored volume, so do not compare one with the other.
The level changes through the year and from year to year, and the pale ring on the rock walls shows where it stood before. Fees, cruises and viewpoints are on our Lake Mead guide.
Time zones at the dam
Nevada and Arizona keep different clocks for part of the year.
Nevada
Pacific Standard Time is UTC-8 and Pacific Daylight Time is UTC-7. In 2026 daylight time runs from 8 March to 1 November.
Arizona
Mountain Standard Time, UTC-7, all year, with no daylight time.
What that means
In summer both states show the same clock. In winter Arizona is one hour ahead. For visit times, see Hoover Dam hours.
Building the dam in brief
Work ran from 1931 to 1936. The first concrete went in on 6 June 1933 and the last concrete in the dam on 29 May 1935. President Franklin D. Roosevelt dedicated the dam on 30 September 1935, and the formal acceptance of dam and powerplant followed on 1 March 1936. Dedication and completion are two different dates.
About 21,000 men worked on the project in total. The average on site was 3,500, and the peak was 5,218 in June 1934. The official count of industrial deaths at the site is 96. Higher counts, such as 112, include earlier survey accidents. The full story is on the history page.
Where to read on
Pages that go with the numbers.
Hoover Dam history
From the Boulder Canyon Project Act to the dedication in 1935.
The Memorial Bridge
A free walkway with a view down on the dam.
Lake Mead
Level, fees, cruises and viewpoints.
Another large Colorado River reservoir, Lake Powell near Page, has its own guide at Lake Powell.
Hoover Dam facts: frequently asked questions
How tall is Hoover Dam?
726.4 feet (221.4 m) from the foundation to the crest. The crest is 1,244 feet (379.2 m) long.
How much concrete is in Hoover Dam?
The dam body holds 3.25 million cubic yards (about 2.485 million m³). The dam, powerplant and related works together hold 4.36 million cubic yards (about 3.333 million m³), a total often rounded to 4.4 million.
How much power does Hoover Dam make?
Rated capacity is about 2,080 MW including the two station-service units, from 17 main turbines. Drought has cut generation by about 30 percent in 2026, so actual output is lower.
Is Lake Mead full?
No capacity figure tells you the level today. The historical capacity of about 28.9 million acre-feet belongs to a full lake at 1,221.4 feet. Check the current level before you go.
Do Nevada and Arizona have the same time?
Only in summer. Arizona keeps Mountain Standard Time all year, and Nevada changes to daylight time. From 1 November 2026 Arizona is one hour ahead.
Is this the official Hoover Dam website?
No. This is an independent guide, not the official site of Hoover Dam, the Bureau of Reclamation or the National Park Service, and not connected to any tour operator.