Stability under seismic and probable maximum flood loads was performed for a 345-foot-high thick arch concrete dam located in the Northern California. The construction of this dam was completed in the 1920’s and its hydropower structures are regulated by the Federal Energy Regulatory Commission (FERC).
This concrete dam built in the 1940s includes a gated spillway section, powerhouse, and nonoverflow sections in the center of the dam with zoned fill embankment on the left and right sides of the concrete structures. Concrete core walls were constructed in the embankment wrap around areas to provide seepage control. Early in the service life of the facilty settlement in retaining walls on the crest and downstream rotational movement of the concrete core walls were observed. Retaining wall settlements on the order of several feet and core wall deformations on the order of 5 inches in the downstream direction were recorded. The objective of the project was to identify and fill data gaps related to dam performance, develop comprehensive models of the structures, identify causal mechanisms, and perform a field investigation to evaluate the conditions contributing to deformations and the current state of the dam related to risk driving Potential Failure Modes (PFMs)
Portugues Dam is a 220-foot-high and 1,230-foot-long Roller Compacted Concrete thick arch dam located in Ponce, Puerto Rico. The dam is part of the U.S. Army Corps of Engineers’ (USACE) Portugués and Bucana flood risk management project, designed to reduce impacts of flooding in and around the municipality in the southern region of the Island.
This concrete gravity dam is approximately 77 feet high and 375 feet long and supports a reservoir that primarily serves the accompanying hydroelectric plant that supplies power to the nearby communities.
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