bedrock, varies in depth from to and totals . A two-line grout curtain reaches depths of below the foundation in the north segment of the East Dam and in the south segment. Because of the amount of material used in the construction of the east dam, some of the biggest trucks in the world were used. Twelve Caterpillar 789 dump trucks were used in construction of the East Dam. Saddle Dam The Saddle Dam rises above the lowest point in the Domenigoni Mountains ridgeline of the north rim and is around long. The dam was built to increase the storage capacity of the lake, which would have been limited due to the lower ridge in this area. It is founded completely on phyllite and schist bedrock. To minimize foundation seepage, a two-line grout curtain extends up to below the foundation. Filling the lake Filling of the lake began in 1999 with water from the Colorado River Aqueduct and San Diego Canal. Water first entered the forebay, a — — basin that held the water before being pumped through the pumping station. The pumping station, named after one of the founders of the MWD, Hiram W. Wadsworth, features twelve pumps for moving water from the forebay to the intake-outlet (I/O) tower. In 2001, four of the twelve pumps were converted to hydroelectric turbine generators capable of producing 3 megawatts of power each. If all the pumps were converted, the entire facility could produce up to 40 megawatts of power. Water is pumped from the pumping station, located just outside the west dam, through a long, diameter pipe and into the lake via the I/O tower. At peak rate, water flowed into the lake at per second. Filling of the lake finished in 2003 In 2009, the lake began being filled with water provided by the Inland Feeder after nearly two years without a source. The water replenished much of what was lost after drought conditions required the MWD to tap into the lake. Water from the Colorado River Aqueduct is not being used due to the threat of the Quagga mussel, an invasive species that has already contaminated other Southern California lakes served by the aqueduct. Paleontological finds During excavation, bones and skeletons were found from extinct mastodons, mammoth, camel, sloth, dire wolf and long-horned bison. Paleontologists from the San Bernardino County Museum in Redlands, California uncovered thousands of fossils in