Trinity Dam, an earth embankment structure high, was the tallest embankment dam in the world at its completion in 1962 (it was surpassed by Oroville Dam, also in California, in 1968). Trinity Lake can store a maximum of , or about twice the Trinity River's flow at this point. Below Trinity Dam is the much smaller Lewiston Dam, the actual point at which the water is diverted. The Clear Creek Tunnel conveys water under the Trinity Mountains to the Whiskeytown Lake reservoir, and from there it flows through the Spring Creek Tunnel to join the Sacramento River at Keswick Dam. Along the way the water drops some through three hydroelectric plants, generating nearly one billion kilowatt hours each year. Water flow data for the Judge Francis Carr hydroelectric station located at the end of Trinity Tunnel indicates an annual average of , or , diverted from the river between 1963 and 2013.