He didn't get financing for the project until late 1868, when a disastrous mine fire deep in the Comstock mines killed hundreds of miners. His tunnel would have offered an escape route that would have saved many lives.
The mines depth, by then, was well below the tunnel access-opening that they finally made into the Savage Mine drifts in July, 1878.
Sutro, himself, insisted on helping tunnel through the last few yards to the Comstock mining area. They completed two lateral expansions to other Comstock drifts and when several mining companies started to pump water through the tunnel, Sutro's "hairbrained" project had comleted 33,315 feet of tunnelling.
In 1880, alone, they pumped two billion (2,000,000,000) gallons of water through it. The mine owners refused to pay the $2.00 per ton fee to haul ore out the underground rail way, however.This made the tunnel less profitable.
The mines did drain the shafts, using the Sutro Tunnel, until 1940.
Adolph Sutro sold out and moved to San Francisco in 1878. He died a millionaire, in that city, August 8, 1898. He had taken his meager returns from the Tunnel and invested in San Francisco real estate, at depression era prices in 1879.
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