An old Aswan Dam was built between 1898 and 1902. It was a very big hydrological project undertaken by the British to increase irrigation and hydro-electric energy. However, as Egypt's population was growing rapidly, a larger dam was needed to cultivate new land and increase supplies of electricity. Work began on the High Dam in the 1960's and was completed in 1971. Although it was later discovered that the dam had environmental disadvantages , there were also numerous advantages, as the High Dam can store surplus water over a number of years, balancing low floods against high and ensuring a good harvest every year. The Dam has already saved Egypt from the worst drought during the 1980's.