|Client||San Francisco Public Utilities Commission|
|Contract works||Construction of a new dam|
The Calaveras Dam is part of a system that provides drinking water to 2.5 million people in the greater San Francisco area. In 2001 the existing dam was deemed seismically unsafe and has been operating at less than full capacity ever since. HOCHTIEF subsidiary Flatiron has been working since 2011 to replace it with a stronger structure. During the course of the work, a total of 5.5 million cubic meters of rock and earth will be moved in order to construct the new dam, which will measure a good 64 meters high. The project also includes the construction of approaches and tunnels. When the replacement is complete, the old dam will be submerged underwater. Flatiron pursued a series of measures to minimize the environmental footprint, such as fish passages and constant monitoring of the air quality to prevent asbestos contamination.