A Denver suburb has finalized an unusual deal to acquire water from an inactive gold mine.

Aurora city officials said Friday the $34 million deal gives the city the rights to about 1,400 acre-feet of water a year from the London Mine outside Alma, about 100 miles (160 kilometers) to the west.

An acre-foot is enough to supply one typical U.S. household for a year.

City officials say the water would normally flow into the South Platte River, which eventually passes through the Denver area, but a geologic fault traps it in the Park County mine.

A graphic explaining how the London Mine water purchase works. (Handout)

Aurora isn’t purchasing the mine itself.

City officials say mines aren’t a common supplier for utilities, but water is increasingly harder to find in Colorado. Like other cities, Aurora is searching for new sources as its population grows.

“Looking for new water supplies in the arid west requires innovative thinking,” Marshall Brown, director for Aurora Water, said in a written statement. “This is a supply that historically has not been tapped by water providers, but the easier supplies are gone.”

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Aurora Water says it is only purchasing the mine’s water rights — the company MineWater will continue to be responsible for the mine property, wells and associated permits.

The city added that Aurora Water “completed substantial due diligence prior to this initial closing. “

Colorado Sun staff writer Jesse Paul contributed to this report.

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