1. Virtual Field Trip (Spring Break 2007)

2. Hoover Dam Hydroelectric facility
Located on the Colorado River on the Arizona/Nevada Border
Construction started in 1931
Dam was completed in 1935 two years ahead of schedule and under budget!

3. Dam Data Arch Gravity Dam 726 feet tall 1244 ft long
45 ft wide at the top
660 ft wide at
the bottom
3.25 million cubic
yards of Concrete

4. Bird’s Eye View

5. Power plant Facts
The power plant at the base of the Dam has 17 Commercial generating units. (shown on next slide)
Capable of generating 2080 Megawatts

6. Nevada Wing with 8 Generators

7. Schematic of the Dam

8. There are 4 intake towers
2 on the Arizona side and 2 on the Nevada side.

9. How power is Generated
Water passes through screens on the intake towers and flows through the penstocks (30 ft in Diameter) to the generators falling an average of 420 feet. (head)
Water reaches a speed of 85 mph by the time it reaches the generators.

10. Water from the Penstock turns a shaft on the generators.
Rotors, made up of electromagnets, are connected to the shaft and spin around a coil of copper wire, generating an electric current.

12. Hoover Dam Can Generate 2080 Megawatts

13. Transmission Lines
Lines Deliver
power to NV,
AZ and CA

14. Lake Mead Flooded The Black Canyon of the Colorado River
Covers 247 mi 2
Popular recreation spot for boating, fishing and water sports
Flooded many small communities including St. Thomas NV.
White bathtub ring marks the 1983 high water mark result of the El Niño

15. Before the Dam: Black Canyon

16. St. Thomas
Founded by Thomas Smith, a Mormon settler in The town was a farming and business community until 1938 when the area was flooded by Hoover Dam, as Lake Mead filled.

17. Diverting the River

18. Construction at Night, July 1934
To learn more about the Construction of Hoover Dam visit this website:

19. Endangered Fish
At least two species of fish have had a major decline since the construction of Hover Dam, the Razorback Sucker (right) and the Bonytail (left)

20. Bonytail
This fish was listed as endangered in There are no known breeding populations left in the wild. Reintroduction is happening through stocking in the areas shown on the map.

21. Razorback Sucker
This fish is limited to 25% of its original range. Most of the population consists of adults due to low survival rates of young fish. The hump on the fishes back provides stability in turbulent water.

22. Reasons for decline
Alteration of the Colorado River system from a turbulent river to a series of calm reservoirs and channelized reaches
Nurseries of the fish have been flooded
Dams block upstream migration
Non-native sport fish
Lack of warm seasonal flow, water from the dams is always cold.
Other introduced animals, plants, pathogens and contaminants.

23. Information on Endangered Fish

24. Downstream Water in the Colorado River is always cold
Flooding no longer scours the banks and exotic species such as tamarisk have become common
Fertile silt in no longer deposited during floods