Three months after the catastrophic collapse of the Baltimore Francis Scott Key Bridge with the clean-up of the shipping channel completed in an extraordinary effort "under unified command" at a cost of about $150 million, the only certain thing is that the old bridge is gone. It is uncertain how the new bridge will look, how tall it will be, how far it will span, how many lanes it will have and who will pay for it. That is a lot of uncertainty, some on account of all the chaos in Washington and some on account of a process called “progressive design-build” (PBD).
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The Francis Scott Key Bridge, a landmark and a gateway to Baltimore, 1.6 mile long, longest span 1,200' (Photo: A. Perna/SUN) |
The matter of the new bridge has been thrusted into the hands of Maryland Transportation Authority (MDTA), the agency in charge of Maryland's toll roads and toll facilities. Part of the Maryland Department of Transportation and created in 1971, these folks have built big stuff before, the Inter-County Connector (ICC), the MD 95 toll lanes north of the Harbor tunnel and the giant interchange with I-95. They were in charge of the construction of the Fort McHenry tunnel (1985) and oversaw the completion of the second span of the Bay Bridge (1973). Recently they completed the Middleton Nice bridge. A current MDTA investigation is the construction of a third Bay bridge.
But all of those projects had been on the books for decades, were thoroughly planned, designed and eventually included in the capital transportation investment plans. Some projects, such as the ICC were highly controversial and used innovative funding (GARVI bonds) and construction methods (Design-Build). Nothing compares to a project that originated overnight, has no firm funding and is estimated to cost $2.7 bn and to be completed in just 4 years.
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Slide from the Industry Day: Very few specifics
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Nevertheless, the MDTA went to work and put out a request for proposals (RFP) at the end of May. Responders had to be quick, the deadline for a response was June 24. The selected bidder is scheduled to be announced in July.
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The general set-up of "progressive design build" (MDTA Slide from Industry Day)
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The 54 page RFP with a 139 page appendix is very cursory and leaves almost everything open for the two-step "progressive" approach in which a design framework is jointly created between MDTA and the successful bidder, followed by construction by the same team if the price is right.
The process involves a single contract that unites MDTA with the selected PDB team, which includes contractor and designer roles. This procurement will select a qualified team for initial services to develop the project scope and requirements in collaboration with MDTA and project stakeholders. Upon successful completion of Phase 1, the PDB entity will have exclusive negotiating rights for Phase 2, which includes project final design/engineering and construction. In the event a guaranteed maximum price is not agreed upon, the MDTA will deliver the work under a separate contracting mechanism. (MDTA press release)
It is the point of "progressive design-build" to save time by working out the design between owner, designer and contractor. This aims to avoid the possibility that a design created by MDTA would take months or years to prepare only to be revised if the construction cost would come in too high at the time of bid. However, without any design and without funding it is hard to know what is "too high", even if a cost framework has been established.
It isn't obvious, why the MDTA wouldn't at least stipulate a few design parameters as a given, even within the progressive design-build approach. During the "industry day" that preceded the RFP 1700 people registered indicating massive interest very little information was given about what would drive the redesign.
An unsolicited proposal from before the RFP submitted to MDOT soon after the collapse could have provided ideas and insights. The proposal, as reported, included higher vertical clearance and a much wider span across the shipping channel that would place the pylons in shallow waters outside the reach of big ships and thus avoiding the need for costly “dolphins” to protect them.
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Corpus Christi, TX Harbor Bridge before (Truss bridge) and after (Cable stayed): Higher and wider (205' clear ht) |
Clarifying design principles in some kind of performance specification would put all bidders on equal footing, literally and figuratively, a goal of any typical request for proposals, popularly known as comparing apples to apples.
Questions abound:
- Should the new bridge should sit in the exact same vertical and horizontal alignment as the old one or whether it should wider and higher? The port indicated that a higher bridge is needed.
- MDTA received a determination from the federal government that they would grant the project a "categorical exclusion" (CE) which eliminates the time consuming preparation of a full environmental Impact Statement (EIS) under NEPA. At which point would modifications in width, height and spans challenge the assumption that a new bridge would not create additional environmental impacts?
- Closely related to the question of design metrics is the question whether the concrete approach parts of the bridge could remain or must be demolished. Those ramps over water still stand and were not impacted by the collision and collapse. The RFP states that it is assumed that they would be demolished but doesn't explain why such a costly and time consuming assumption is made nor is it made entirely clear who would be responsible for that demolition and whether such demolition would still fall under a CE.
- What are the required minimum protective measures for the supports?
- Is the projected project cost of $2.7bn realistic and what is it based on?
- Why would we settle for 4.5 years to completion? The projected time of Oct 2028 wouldn't be a speed record in bridge reconstruction after a collapse. Minnesota did it faster and spectacularly also Italy. There a big bridge in Genoa was redesigned and completed in 18 months involving local architect Renzo Piano for attractive design. (The RFP allows for faster completion, of course and promises incentives to do so).
The collapse of the Key Bridge was a traumatic event that in an instant not only blocked one of the nation's busiest ports, but also eliminated a local landmark and severed a vital regional traffic artery that is urgently needed for truck traffic, commuting and a complete freeway network. The trauma shouldn't be followed by the drama of delays and cost overruns as in the case of the Corpus Christi Harbor Bridge or the Gordie Howe International Bridge towards Canada. The latter was scheduled to open this year but is delayed and has recently been estimated for a final cost of $4.7bn US dollars.
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Cable stayed bridges: Gordie Howe International Bridge, MI (2024), 1.5 miles long, 138' clearance, delayed completion, cost $4.7 bn |
Little of Governor Moore's word power, which he frequently and effectively used during the clean-up efforts under the "Unified Command", has been used to speak about the new bridge design or set the framework for this extraordinary task.
It was frequently mentioned how much the Key Bridge meant for Marylanders or Baltimoreans and how its sudden loss has carved a deep scar in the minds and hearts of many. What does this trauma mean for the rebuild process and the design one should expect for the replacement bridge?
Such non-technical notions do not come easy to the bureaucrats and engineers who usually manage RFPs but they should set the stage for a task that is like none before.
The new bridge needs not only to be built extraordinarily fast, it has to be of such an excellent design that is it can become a recognizable and authentic landmark again. The new bridge needs to respond to rising sea levels, larger ships and increasing demands for alternative transportation modes such as transit, bikes and pedestrians that have previously not been accommodated on the bridge.
The public can only hope that communication about what will happen next and how the MDTA will select the winning partner, and how it will establish metrics for design will be ramped up in the coming weeks. It can be expected that there are lots of interests that want to have say in this. Already there has been discussion whether a new bridge should have more vertical clearance than the 185' feet the old bridge had. The public deserves nothing less than participation and full transparency, no matter that everything has to happen fast.
Klaus Philipsen, FAIA
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