A total of 3 @,@ 250 @,@ 000 cubic yards ( 2 @,@ 480 @,@ 000 m3 ) of concrete was used in the dam before concrete pouring ceased on May 29 , 1935 . In addition , 1 @,@ 110 @,@ 000 cu yd ( 850 @,@ 000 m3 ) was used in the power plant and other works . More than 582 miles ( 937 km ) of cooling pipes was placed within the concrete . Overall , there is enough concrete in the dam to pave a two @-@ lane highway from San Francisco to New York . Concrete cores was removed from the dam for testing in 1995 ; they showed that " Hoover Dam 's concrete have continued to slowly gain strength " and the dam is composed of a " durable concrete having a compressive strength exceeding the range typically found in normal mass concrete " . Hoover Dam concrete is not subject to alkali – silica reaction ( ASR ) as the Hoover Dam builders happened to use nonreactive aggregate , unlike that at downstream Parker Dam , where ASR have caused measurable deterioration .