Friant Dam is Constructed on the San Joaquin River

Friant Dam, located 25 miles northeast of Fresno, California was completed in 1942. The dam controls the San Joaquin River flows, diverting most its water to a million acres of agricultural land in Fresno, Kern, Madera, and Tulare Counties in the San Joaquin Valley. The reservoir, Millerton Lake, first stored water on February 21, 1944. It has a total capacity of 520,528 acre-feet, a surface area of 4,900 acres, and is approximately 15 miles long.

Chinook Salmon Runs Go Extinct on the Lower San Joaquin River

It was reported that during the 1940's before the construction of Friant Dam, the San Joaquin River had an excellent spring run and a small fall run and that the spring run was probably the most important one in the Central Valley. The spring counted 30,000 or more fish in early 1940's and a minimum of 56,000 spawners.

As a direct result of the completion of Friant Dam in 1942, both the spring and fall salmon runs were extirpated from the upper San Joaquin River above the confluence with the Merced River. Friant Dam cut off at least a third of the former spawning areas, but more importantly, the Friant Project essentially eliminated river flows below the dam, causing about 60 miles of river below "Sack Dam" to completely dry up.

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