There are six of them on the Colorado river. Glenn Canyon dam, Hoover dam, Davis dam, Parker dam, Palo Verde diversion dam and Imperial dam.
Hoover Dam.
The Hoover Dam
There are about 20 on the Colorado but Hoover Dam is the largest.
Hoover Dam =)
Consider thes 15 river systems that all have their headwaters in Colorado: Arkansas River. Canadian River. Colorado River. Dolores River. Gunnison River. Laramie River. Little Snake River. North Fork...