Due to the accelerated schedule of the project, the request for proposals allowed only a 40-day window to develop design innovations and a construction cost for the work. Through this fast-tracked process, our team, as the designer of record, partnered with the contractor to brainstorm ideas and develop the design details necessary for the contractor to prepare a lump-sum bid for the bridge and approaches.
Initially, the owner provided a preliminary design of the long-span bridge that was developed by the client’s owner’s engineer. During our evaluation of the preliminary design — and vetting out during numerous one-on-one meetings with the owner — we were able to identify several opportunities to improve the design to achieve significant cost and schedule savings while also improving the longevity and quality of the project. Some of these enhancements included eliminating multiple spans of the bridge, removing retaining walls, and utilizing innovative river pier construction techniques and cost-saving girder designs.
Upon project award, we expedited the approvals of the various stakeholders and government agencies and coordinated plan-in-hand meetings for over-the-shoulder reviews to facilitate accelerated permit approvals. In this way, we were able to convey the design changes and acquire the necessary buy-in from these critical stakeholders.
As part of the design-build delivery process, in which construction overlaps design, permit approvals were required at various times to meet the start of construction for each of the eight construction packages. The last package was approved and permits obtained within nine months of the start of design, meeting the accelerated approval process for the final construction package.
Other coordination efforts included developing innovative stormwater conveyance solutions that eliminated unneeded detention but required coordination with adjacent private developments. This solution reduced the downstream impacts to swales maintained by IDOT, which in turn eliminated the need for additional permits. We also identified modifications to the profile to eliminate impacts to an intersection under IDOT’s jurisdiction, avoiding delays for additional permits and balancing earthwork on both sides of the river.