Plumbing problem at Glen Canyon Dam threatens water supply of Colorado River system

Plumbing problems at the dam holding back the second-largest reservoir in the U.S. are spurring concerns about future water delivery issues to southwestern states supplied by the Colorado River.

Federal officials recently reported damage to four tubes known as "river outlet works" at Glen Canyon Dam on the Utah-Arizona border. The dam is responsible for generating hydropower and releasing water stored in Lake Powell downstream to California, Arizona, Nevada and eventually Mexico.

The U.S. Bureau of Reclamation...