- 2055 - 2099: Colonel (later General) Orson Masters
- 2099 - 2126: General William Masters
- 2126 - 2150: General Alec Masters
- Construction begins.
- The facility begins operation under the command of Colonel Orson Masters.
- The facility loses all contact with the outside world.
- The last refugees from outside the Grand Canyon Province, specifically Las Vegas, reach the Garrison.
- Colonel Orson Masters promotes himself to General to better reflect his increased responsibilities in leading the community that the Hoover Dam Garrison has become.
- Command passes to General William Masters.
- Responding to attacks on its scouts and the rise of the CHOTA leader Redhand, forces from the Hoover Dam Garrison attack the CHOTA settlement of Five Points. In response the CHOTA send a group of mutant assassins into the Hoover Dam Garrison, killing General William Masters. His son Alec Masters assumes control of the Garrison.
- Under Alec Masters, the Hoover Dam Garrison becomes a despotism.
- The CHOTA are forced back to CHOTA Gulch and Siller's Canyon.
- Mutants are rounded up by the hundreds for experimentation, most never to be seen again.
- Alec Masters attacks the Monastery, home of the Lightbearers, capturing their leader Shakti and scattering the order.
- After years of conflict, the CHOTA storm the Hoover Dam Garrison with assistance from the Travelers and Vistas.
- Tired of years of abuse, the people of the Garrison rise up against Alec Masters as well.
- The Garrison is destroyed in the ensuing battle and the dam abandoned.
- Alec Masters is killed by the CHOTA.