At its peak in 1997 and 1998, the reservoir construction project employed an average of 1,800 people. At times, more than 1,900 people labored in building the reservoirs three dams. From start to finish, about 5,000 people were employed by the construction project.
Some of the biggest trucks in the world were used to build
Diamond Valley Lake. Twelve Caterpillar 789 Model trucks were
used in construction of the East Dam. When full of rock, trucks
weighed 350 tons. They cost $1.4 million each. Their 1,800-horsepower
engines burned 40 gallons of fuel per hour. They were so big
they could not be driven legally on public streets. They were
brought to the reservoir in pieces, assembled on site and
then disassembled before being hauled away in trucks.