Associated Press - September 8, 2009 1:55 PM ET

SEATTLE (AP) - Two huge machines digging sections of a 13-mile tunnel for a new King County sewage treatment plant are broken and stuck about 300 feet below Bothell and Lake Forest Park.

Because of the pressure of underground water it takes divers to make repairs.

The Seattle Times reports the contractor and builder of the machines are looking at millions of dollars in unanticipated costs. Meanwhile they hope to get one boring machine moving again by the end of the year.

The 18-foot-diameter tunnel will carry treated waste from the new plant north of Woodinville to Puget Sound near Edmonds.

Even before the boring machines broke down, the start of the $1.8 billion treatment plant slipped from 2010 to August 2011.

Information from: The Seattle Times, http://www.seattletimes.com

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