mayor sunny jim rafh turned to michael to mastermind the project. michael was a force of nature. air fwant in some ways but also a man's man. he supper advised the construction and it was the greatest engineering seats in the united states. >> the remow location of dam and reservoir made getting to the site a challenge. >> they had to get access to the slopes of the sierra nevada so they her to build a railroad to get construction equipment and materials into the site. they had to generate power so they built another reservoir to generate power and they did a remarkable amount of work with much less sophisticated equipment than what we have today. >> concrete for the dam was processed at a plant just upstream from the construction site, using sand and rock from the valley. nearly 400,000 yards of cubic concrete were poured around the clock. >> oshansee was a detailed oriented guy. he was having his man dig down the bedrock and they would dig and dig and pull, you know, out debris and they come and say, okay, we've gotten down. we're down far enough. we need to personally look at

mayor sunny jim rafh turned to michael to mastermind the project. michael was a force of nature.fwant in some ways but also a man's man. he supper advised the construction and it was the greatest engineering seats in the united states. >>ipment and materials into the site. they had to generate power so they built another reservoir to generate power and they did a remarkable amount of work with much less sophisticated equipment than what we have today. >> concrete for the dam was processed at a plant just upstream from the construction site, using sand and rock from the valley. nearly 400,000 yards of cubic concrete were poured around the clock. >> oshansee was a detailed oriented guy. he was having his man dig down the bedrock and they would dig and dig and pull, you know, out debris and they come and say, okay, we've gotten down. we're down far enough. we need to personally look at it and say, no, dig deeper. >> in may 1923, the dam was completed and named first chief engineer and behind it, an 8-mile chef of the hetch hetchy valley was flooded and holding back 115 billion gallo