In Washington DC, the DC Clean Rivers Project has awarded the first of its four major design-build tunnel contracts to Traylor/Skanska/Jay-Dee JV with designer Halcrow. Technical and price proposals for the Blue Plains Tunnel were received from three shortlisted design-build teams – Kiewit/Clark, Traylor/Skanska/Jay-Dee and Kenny/Shea/Obayashi – in January, with high to low prices ranging from $330.5M to $358M. Evaluation and scoring of the technical (35%) and price (65%) proposals ultimately resulted in a combined highest score and lowest bid by Traylor/Skanska/Jay-Dee. The DC Water Board of Directors is due to officially approve the $330.5M contract on April 7, with Notice to Proceed expected in late April. EPC has been selected to carry out construction management on the project.
The Blue Plains Tunnel is the longest of the four tunnels in the DC Clean Rivers Program, at approximately 24,000ft long (7,315m) and 23ft (7m) i.d., and will include five shafts between 50ft (15m) and 132ft (40m) in diameter and 110ft (34m) and 170ft (52m) deep. Approximately 9,000ft (2,743m) of tunnel alignment passes below the Potomac and Anacostia rivers. The tunnel will be constructed at depths of 100ft (30m) using an EPBM through ground consisting primarily of clay and silt deposits and will be lined with a fiber reinforced precast segmental liner. Tunnel excavation is expected to begin in 2013 with completion in 2015.
“We were very pleased with the quality of proposals received for the Blue Plains Tunnel and now hope for the same result with the Anacostia River Tunnel,” says Rafael Castro, Principal with Jacobs Associates, the tunnel and geotechnical consultant for DC Water.
The Blue Plains Tunnel is only one component of the DC Clean Rivers’ $2.5 billion Long Term Control Plan (LTCP). Implementation of the LTCP is on schedule to achieve the first of its Consent Decree–driven milestones, which requires the Blue Plains Tunnel, Anacostia River Tunnel, and several associated near-surface facilities to begin operation by March 23, 2018.
Geotechnical explorations and engineering work associated with the Anacostia River Tunnel, the second of the four major design-build contracts, are expected to be completed by the end of 2011. At its southerly extent the Anacostia River Tunnel connects to the Blue Plains Tunnel at Poplar Point, east of the Anacostia River. The tunnel crosses beneath the Anacostia River just north of the new 11st Street Bridge and terminates just south of RFK Stadium within Nation Park property.
The tunnel will be approximately 12,500ft long (3,840m), 23ft (7m) in diameter, and 100ft (30m) deep. The work will include five 90ft to 100ft (30m) deep shafts — three between 30ft to 75ft (23m) in diameter, and two 12ft (3.6m) in diameter. Adit connections are required between the tunnel and three of the shafts; these adits will be between 4ft and 10ft (3m) in diameter. The tunnel will be constructed predominately in silty and clayey sands. Similar to the Blue Plains Tunnel, it will require a pressurized face TBM. The contract will also include activation of the storage system and all of the diversion, odor control, and venting facilities between RFK Stadium and the Blue Plains Advanced Wastewater treatment Plant.
Design-build procurement for the Anacostia River Tunnel is scheduled to commence late in 2011. The preliminary schedule contemplates advertisement of an RFQ in November 2011, RFP documents released to shortlisted teams in April 2012, proposals due in December 2012, and a contract award by May 2013. Teams interested in keeping their eye on the Anacostia River Tunnel should contact DC Clean Rivers Project Director, Carlton Ray, for updates on email@example.com.