1. Primary water release is through the eight generators that make electricity. The penstocks are at an elevation of 3470 mean sea level (msl), approximately 333 feet above the bottom of the reservoir. The Bureau of Reclamation makes it a goal to release all of the monthly volume of water required for downstream use through the penstocks.
2. River Outlet Works. The secondary release point is from the four hollow jet tubes located at elevation 3374 msl, about 96 feet below the elevation of the penstocks and 237 above the bottom of the reservoir. The four hollow jet tubes have no electrical generators and are used primarily to release excess water from the reservoir.
3. Spillways. Two spillways were constructed at Glen Canyon Dam, one on each side. They can function only when the reservoir reaches within 50 feet of being full. They are the last line of defense for flood control and downstream releases.

Two river outlets diverted water around the damsite during construction. Both are at river level and were cemented closed in 1963 following completion of the dam. The lower end of both spillways became the bottom section of the two spillways.