 As the technology of electric power transmission improved , the Lower Colorado was considered for its hydroelectric @-@ power potential . In 1902 , the Edison Electric Company of Los Angeles surveyed the river in the hope of building a 40 @-@ foot ( 12 m ) rock dam which could generate 10 @,@ 000 horsepower ( 7 @,@ 500 kW ) . However , at the time , the limit of transmission of electric power was 80 miles ( 130 km ) , and there were few customers ( mostly mines ) within that limit . Edison allowed land options it held on the river to lapse — including an option for what became the site of Hoover Dam . 
