State to let bidding flow for right to Marlette water pipe work

It's money time next week, as the state will open bids on a major project to replace a section of the pipe that brings water from Marlette Lake to Carson City and Virginia City.

The project will replace 3,600 feet of pipe above the Lakeview Tank where the inverted siphon begins up to Sawmill Canyon, project manager Dan Daily said Thursday in a pre-bid meeting with more than a dozen potential contractors.

The new, welded steel pipe will be 24 inches in diameter and will replace the more than 50-year-old 18-inch line that now feeds the siphon.

The Marlette Water System was built in the 1800s. Considered an engineering marvel at the time, it uses gravity to move water from Marlette Lake above Lake Tahoe down to Lakeview, under U.S. 395, then up into the Virginia Range to Virginia City. It does so using an inverted siphon that begins at the Lakeview Tank.

The pipe being replaced feeds water from the lake to the siphon as well as the line that connects to the Carson City water system. Daily said parts of the pipe are so old and deformed that they resemble "a taco shell" and lie exposed above the roadway that the existing line follows. But he warned the contractors that, because the system is Virginia City's sole water source, the old pipe must remain in service until the new line is tied in.

He also warned them that not only is access difficult - by a narrow, winding mountain road - but that the area is environmentally sensitive, as well as a destination for hikers and bicyclists during the summer. The road can be closed during the week, but it will have to be open to the public on weekends, he said.

In addition, there are homes at the bottom of the hill where the Public Works equipment yard is, so the eventual contractor will have to monitor noise and dust levels.

The estimated cost of the project is $2 million.

Daily said the work is planned to start in late June or early July and be completed by the end of October, when winter weather normally makes the gravel road up the mountain practically impassable.

After bids are opened Thursday, the state Public Works Department expects to award the contract within two weeks.

The project is being done for Carson City, which obtained a federal Environmental Protection Agency grant to do the design work. The construction will be funded by revenue bonds paid off by city water customers.

But it isn't part of the water/sewer projects that were approved by the Board of Supervisors this week. These revenue bonds were approved in the past.

City Manager Larry Werner said Carson City will be able to get more water from the system with the new pipe, mostly because it will reduce losses from leaks and improve flow.

"It will improve overall delivery," he said.

Darren Schulz, the city's deputy public works director, said the problem with the pipe is that it was partly crushed by construction equipment driving over it, reducing the amount of water that can flow through it. He said the new and larger pipe will enable the city to get more water, especially during peak summer months, when it is most needed.

The pipeline replacement will be the third major project to improve the water system in the past three years.