Part of the Central Valley Project, the dam was built by the United States Bureau of Reclamation (USBR) and was completed in 1942 with the exception of the drum gates being installed in 1947.

[1] The lake stores water for irrigation, which is distributed by the Madera and Friant-Kern Canals to the San Joaquin Valley.

The California Office of Environmental Health Hazard Assessment has issued a safe eating advisory for fish caught in the Millerton Lake due to elevated levels of mercury.

The desiccation of the river has caused the degradation of large stretches of riverside habitat and marshes, and has nearly eliminated the historic chinook salmon run that once reached about 15,000 fish each year.

Reduction in flows has also increased the concentration of pesticide and fertilizer runoff in the river contributing to pollution that has further impacted aquatic species.