Dragados to build the Thimble Shoal Channel Tunnel

29 July 2016

US - The Chesapeake Bay Bridge and Tunnel (CBBT) Commission announced July 27 it awarded the Dragados Team a contract to construct a new parallel tunnel at the Thimble Shoal Channel.

The Dragados Team, a joint venture composed of Dragados USA, Inc., and Schiavone Construction Company LLC, submitted the lowest price proposal at USD 755,987,318.

The Dragados Team’s proposal included a bored tunnel and construction will begin on Island 1 in the fall of 2017. Total construction of the parallel tunnel at the Thimble Shoal Channel is expected to take approximately five years.

According to CBBT, on May 27 the commission invited each of the three teams that had submitted fully-compliant proposals by the original due date of April 29 to submit revised proposals for a re-scoped project after all of the original price proposals exceeded the cost estimate. It said, “The re-scoping of the project was focused solely on the reduction of costs by reducing or eliminating non-critical elements of the project without compromising the technical safety factor of the design, customer safety, and maintenance life cycle priorities that are specified in the technical requirements of the RFP documents.”

The conceptual design for the project RFP initially included the widening of the man-made islands 250ft to the west of the existing islands to provide physical space for either an immersed tunnel or bored tunnel to transition to the existing trestle alignment of the CBBT.

Jeff Holland, executive director of the CBBT, stated that “the project was originally envisioned with a substantial expansion of the portal islands. As such, the expanded southern island would have created space for the future public amenities at little additional cost.

“When all of the teams competing for the project focused on reducing cost, it became apparent that island expansion could be very limited or non-existent. As a result, the inclusion of the space sizing for the public amenities of a restaurant, retail shop and 200 additional parking spots that would otherwise require substantial island expansion became cost prohibitive and not necessary to meet the basic mission of the CBBT: providing the traveling public with a safe, cost effective, and unique driving experience across the scenic Chesapeake Bay."

This scope change, combined with others, allowed the commission to reduce the cost of the Project by nearly USD 260M from the low price received during the first phase of design-build proposal prices.