The East Maui Irrigation System is Hawaii's most dramatic water story. It began with the construction of the Old Hamakua Ditch built between 1876 and 1878. This privately financed, constructed and managed irrigation system was one of the largest in the United States. It eventually included 50 miles of tunnels; 24 miles of open ditches, inverted siphons and flumes; incorporates approximately 400 intakes and 8 reservoirs.
The first electric power generated by the Theodore Roosevelt Dam for commercial use was transmitted over a high-voltage line to Phoenix, where it was employed to operate the city's new streetcar system.
This is one of the earliest uses of engineered water supply and irrigation systems in the United States. The first of eight original acequias was under construction in 1718 and two are still in operation. The remains of one are visible on the grounds of the Alamo. The Acequias of San Antonio are among the earliest engineered water supply and irrigation systems recorded in the United States. The Acequias served an integral role in the growth and stability of the San Antonio community for nearly 200 years.