Share this post

As of mid-December, RSS JV – a joint venture of Roanoke, Texas-based Oscar Renda Contracting Inc.; Fort Worth, Texas-based Southland Contracting Inc. and SAK Construction LLC of O’Fallon, Mo. – was more than halfway through the Bi-County Water Tunnel project in Chevy Chase, Md. The project will be completed by December 2013, reports James Grissom, project manager with Southland Contracting.

The Washington Suburban Sanitary Commission (WSSC) awarded RSS JV a $112 million contract to bore a 5.3-mile, 10-foot-diameter tunnel with three shafts. It will feature an 84-inch-diameter steel pipe for freshwater transfer to residents in Montgomery and Prince George’s counties. The new line will connect to existing water mains and have the capacity to carry 100 million gallons per day.

‘Miss Colleen’

Construction on the Bi-County Water Tunnel project began in August 2009 with the sinking of two shafts to provide access for and retrieval of “Miss Colleen,” the tunnel-boring machine (TBM) being supplied by SAK Construction. By late November 2010, she had bore through the 4,102-linear-foot eastern leg of the tunnel. “The idea was to go for our shortest run first, turn the machine around and come back and do the long section,” Grissom says. 

In February 2011, when RSS JV was about 1,200 feet into the 24,045-linear-foot western leg of the tunnel, Miss Colleen came to an abrupt halt due to a mechanical failure in one of her gearboxes. The TBM had to be backed up to one of the shafts for disassembly and removal, and the affected portions were shipped to the machine’s manufacturer, The Robbins Co., for repair. “We got it back here on site sometime in June [2011],” Grissom says. 

“We lost about 120 days on our schedule,” he adds. “We were supposed to complete the project by fall 2013, but the owner, WSSC, gave us 120 extra days and pushed out the deadline to December 2013. The owner has been very good to us.”

Rocking Out

RSS JV faced another obstacle in August 2011 when Miss Colleen ran into a pocket of fractured rock and was out of commission for a few weeks. Usually, the hydraulic grippers of the TBM brace against the hard tunnel walls and push the rotating cutter head against solid rock to bore through it. However, when a TBM hits fractured rock, the grippers are not able to do their job and the boring must cease.

“We had to use mechanical means to support the rock, which in this case was steel sets and mesh with grouting behind it,” Grissom notes. “It slowed us down a bit, but we kept moving. Southland likes a good challenge; it keeps us on our toes. But overall, we’ve been fairly lucky. It’s a pretty straightforward project. It’s Southland’s show, if you will. Rock stars go on stage every night and don’t think anything about it. This is our stage. We are self-performing most of the work.”

Team Effort

Grissom says RSS JV has enjoyed working with San Francisco-based Jacobs Associates, which is serving as the construction manager and owner’s representative on the Bi-County Water Tunnel project, as well as global engineering, consulting and construction firm Black & Veatch of Overland Park, Kan., which designed the project. 

Although this is the first time Oscar Renda Contracting and Southland Contracting have formed a joint venture to complete a project, the two contractors are quite familiar with each other’s work. Both contractors are based in Texas and have reputations for completing challenging projects.

Charlie Griffin started Southland and quickly grew it into a national contractor operating in 21 states. Oscar Renda Contracting is one of the premier tunnel contractors in the country having completed more than $2 billion worth of work since 1974.

“They thought it was a good time to team up and do a project like this together,” Grissom says. “The two companies have a good relationship and work well together.”