Maryland officials told the media yesterday that the replacement cost for the Francis Scott Key Bridge in Baltimore is now between $1.7 and $1.9 billion, and that the state hopes to have a replacement structure in place by 2028 by using the “progressive design-build” engineering technique.

Maryland Transportation Secretary Paul Wiedefeld also told the Baltimore Sun that the $350 million payout from the Chubb Group for the state’s insurance policy on the bridge will be transferred to the Federal Highway Administration’s Emergency Relief program for reimbursement of bridge replacement costs (assuming that FHWA does indeed wind up funding the replacement bridge out of the ER program – it is likely, but not guaranteed yet).

Replacing this bridge will be much more expensive than the last two high-profile Interstate highway bridges replaced with federal ER funding. The Interstate 35W bridge in Minneapolis that collapsed in 2007 was replaced at a cost of $234 million, and the Interstate 10 Twin Spans outside New Orleans, damaged by Hurricane Katrina in 2005, cost $803 million to replace.

The Maryland Transportation Authority (MDTA – the MDOT toll facility subgroup that actually owned and operated the FSKB) is hoping to move quickly to select a design-build firm for the bridge project. MDTA is holding an all-comers “Key Bridge Rebuild Virtual Industry Forum” on Tuesday, May 7 from 2-4 p.m. to brief potential consultant firms, contractors, and subcontractors, all of whom should bookmark MDTA’s webpage http://www.keybridgerebuild.com for more information.

What is “progressive design-build”? Well, regular design-build is hiring one firm to perform or manage both the design and construction elements of a project (pretty straightforward). However, in regular design-build, the contractor is hired after the concept and preliminary design of a project are complete – the industry standard is the 35 percent mark of total completeness of design. Then the design-build contractor comes in and finishes the other 65 percent of the design and actually builds the thing.

Progressive design-build would actually hire a design-build firm at the absolute beginning, before the conceptualization or any other design work has been done. (Obviously, this means that the contractor cannot be selected by the usual kind of cash bidding.) The contractor works with the client to develop the project together. A primer from the Design-Build Institute of America sets out the process:

A key feature of progressive design-build is protection of the purchaser through setting a Guaranteed Maximum Price (GMP), putting responsibility for cost overruns above that price on the contractor, not the purchaser. That GMP can either be set before design (“Design to Fixed GMP Value” on the above flowchart), or at the end of final design (“Design Fixed Scope, Then Set GMP Value”), which is more likely in this instance.

Maryland was a leader in using progressive design-build, having used the technique in 2017 on the I-270 Innovative Congestion Management project.