ABSTRACT
Laurel Run Dam, located near Johnstown, Pennsylvania (USA) failed by overtopping in 1977. This 37-foot high hydraulic fill dam was constructed in 1916 for water supply. In the early 1960’s the owner, in response to a need for more water storage, commissioned a study to heighten or replace the dam. Exploration, testing, and analysis showed the existing dam’s strength was inadequate to incorporate it into a much higher structure. Also, the spillway capacity of Laurel Run Dam was substantially less than design storm criteria adopted during the 1950’s. A 137-foot high earth and rock fill dam was designed just downstream.
