A construction team was attempting to build part of a tunnel in Nevada when a cavern began to flood last week—because things can go wrong when you build tunnels—and now the project is being delayed:

Project officials were assessing the damage Wednesday, but the setback could delay completion of the $700 million intake by several months.

"It's too early to know," said J.C. Davis, spokesman for the Southern Nevada Water Authority. "We built some contingency time into the project with the idea that there were going to be some problems. We just didn't know what those problems would be."

The project's manager, Jim McDonald, said the flood occurred when workers in the cavern 60 stories underground hit a water-filled fault, allowing it to empty into the chamber. [...]

"It's a geo-technical issue," McDonald said. "It's not unusual in deep underground tunnel work to find conditions that are adverse." [...]

McDonald works for Vegas Tunnel Constructors, a joint venture of the Italy-based Impregilo group and its U.S. subsidiary, S.A. Healy Co.

Healy is also the primary company involved in the two remaining teams bidding on a deep-bore tunnel under downtown Seattle (two other teams have dropped out). According to a Washington State Department of Transportation document outlining the bidders (.pdf), Healy's "current project experience includes designing and building an access shaft and water intake tunnel located below Lake Mead in southern Nevada."

This isn't to say that Healy is responsible for the leak, only that things can and do go wrong when you dig tunnels. We shouldn't minimize those risks, and we should know who pays when things go wrong. That's the opposite of what most politicians are doing in Seattle: minimizing the risk we face and setting no plan for who pays if the project runs over budget.