PICKWICK DAM (AP) — The Tennessee Valley Authority plans to begin reinforcing the Pickwick Dam against earthquakes this fall.

WAAY-TV reports that the reinforcement will cost about $150 million and require about one million tons of rock and sand. TVA's senior program manager at Pickwick Dam, Bernie Auld, says damage to the 1938 dam and its clay core could cause flooding similar to what Savannah, Tennessee, saw in 2013.

The dam has been equipped with an updated warning system, which added about 30 instruments to measure seismic activity. TVA says work is expected to finish in 2021.

The station says TVA's biggest concern is the dam's proximity to the New Madrid Fault Line. TVA and other groups plan to conduct a training exercise that simulates a large earthquake at fault line in June.