Another procedural impediment to the Hiawatha Corridor LRT project involved the interface between the project's design-build team and the contractor selected to construct the airport segment of the project, twin 1.8 mile tunnels delivered by the Metropolitan Airport Commission using a design-bid-build approach. MAC's contractor was responsible for civil construction and stub-ins for electrical systems, while the design-build team was responsible for track, signal, and catenary power delivery system. The original plan called for MAC's contractor to complete one tunnel first, enabling the design-build team to initiate systems installation in the first tunnel while the second tunnel was completed. However, the MAC contractor fell behind schedule by 102 days, which could potentially have resulted in 3 or more months of inactivity for the design-build team while it waited for the tunnel's completion. To address this, both sets of contractors and the project sponsors developed a detailed plan in which the tunnel would be completed in linear feet segments, which allowed the design-build team to begin systems installation in part of the tunnel while the other contractor finished the rest of it. This kept the two teams active and productively working simultaneously in the same tunnel, 75 feet below the runways of the Minneapolis-St. Paul International Airport.
The initial disconnect between the design-build contractor and MAC's contractor highlights the benefits of a PPP structure where a single entity is responsible and financially liable for performing all or a significant number of functions in connection with a PPP project and the public sponsor does not need to assume the risk that the work of one contractor will impede the work of another.
Sponsors of both the Hiawatha Corridor and T-REX projects orchestrated careful interactions with localities and private property owners regarding project betterments. Both projects were requested to improve facilities near the project to enhance access to or the appearance of the project. In both cases, sponsors responded that the parties would need to pay for design and construction of improvements that were outside the scope of the project. In the case of Hiawatha, the project sponsors were diplomatic in saying "no" to parties interested in improved access who weren't willing to pay for it with private resources. In the case of Denver's project, localities paid for most of the changes, but RTD did contribute to some changes when there was a direct benefit to the agency or its users.