By Kevin Eisenbeis, PE, SE
With Interstate 70 (I-70) serving as a major highway connecting much of the United States, one section of the interstate in the heartland is undergoing major renovations to provide reliable connections for both daily commuters and cross-country travelers. The Lewis & Clark Viaduct is a network of bridges that carries I-70 across the Kansas River, several railroad tracks, multiple streets and the West Bottoms industrial area to connect travelers across Missouri and Kansas.
Originally built in 1907, the eastbound viaduct served as a four-lane, two-level deck truss bridge to accommodate both automobile and pedestrian traffic. Designed by Waddell and Hedrick and known as the Intercity Viaduct, the viaduct was the first roadway bridge to connect Kansas City, Missouri, with Kansas City, Kansas. When it was first built, the Intercity Viaduct carried both eastbound and westbound traffic. The bridge was later renamed the Lewis & Clark Viaduct on Jan. 25, 1969, taking the name of its companion bridge that carries the westbound lanes, which was built to the north in 1962.
With the viaduct last renovated in 1984, many updates were needed to provide an aesthetically appealing and reliable bridge. While the Kansas Department of Transportation (KDOT) deemed the bridge safe for travel, the viaduct had structural issues, was considered functionally obsolete and needed upgrades to meet current design standards. The viaduct, consisting of nine bridges, is inspected by KDOT every two years to evaluate existing conditions and confirm necessary maintenance is completed to meet safety regulations.
KDOT identified several aspects of the viaduct that needed structural updates and required an outside team of engineers to complete the project. By the time construction is complete, the new 2,980-foot-long, 20-span bridge will consist of two-thirds structural steel I-girder and one-third prestressed concrete girder superstructure with 19 new or rehabilitated concrete piers. The bridge is also expected to require 8.8 million pounds of new structural steel, 5,400 lineal feet of new concrete girders, 21,000 cubic yards of concrete and 3.1 million pounds of reinforcing steel throughout construction. The new bridge is expected to decrease maintenance costs that were continually increasing to maintain the original structure. KDOT selected Burns & McDonnell to design the Phase 1 westbound I-70 bridge reconstruction as part of a multiphase project for the Lewis & Clark Viaduct.
With extensive experience addressing the engineering and construction complexities of projects spanning major river crossings, Burns & McDonnell was able to incorporate techniques that minimized disruptions to adjacent properties. Project scope included preparation of final design, field check and final plans, railroad coordination, and coordination of the horizontal and vertical alignment. The team also organized signing, lighting and aesthetic elements, as well as coordinated safety standards to keep construction equipment and signs at an appropriate height to avoid conflicts with nearby Wheeler Downtown Airport.
As part of a multiphase project, Phase 1 necessitated the closure of westbound I-70 for two construction seasons, impacting KDOT; Missouri Department of Transportation (MoDOT); Kansas City, Missouri; and Kansas City, Kansas. Maintenance of traffic and detour plans were developed to prevent major traffic issues around the region. The team also kept public and impacted stakeholders, such as the Fairfax Industrial District and other relevant local businesses, informed about progress. The strategic local communication also served to gather input that would help maintain transportation access throughout the construction process. The traffic studies coordinated placement of appropriate signage to prevent traffic bottlenecks.
Additionally, the team conducted hydraulic studies to determine if construction might contribute to potential future flooding. The studies accounted for multiple stages of future construction and determined that adding new bridge piers would not result in a rise in water level in the final condition.
The visual aesthetic of the bridge and stakeholder input were both vital factors in making key project decisions. In conjunction with the City of Kansas City’s downtown master plan, Burns & McDonnell also coordinated development of comprehensive urban design guidelines that were adopted by the Unified Government of Wyandotte County and Kansas City, Kansas. To shape and design the aesthetic appeal of the viaduct, Burns & McDonnell partnered with Confluence, an urban design firm based in Kansas City, Missouri. The team developed two design themes for consideration by key invested stakeholders –a river prairie theme and an urban industrial theme.
Ultimately, an urban industrial aesthetic approach was chosen after many public meetings involving the design team, owner and community members. The design theme is reflected in the visual appearance of the viaduct, support structures, barriers and retaining walls. This approach will give each phase of the Lewis & Clark Viaduct project a consistent look and feel.
Based on stakeholder input, the team also incorporated a future bike path in the design to accommodate the feature already present in the existing bridge. Bicyclists will continue to be able to use the bridge to cross between the cities, with design considerations that provide space for both pedestrians and bicyclists below the future eastbound bridge. Phase 2 of the project will accommodate for this aspect of the bridge to remain part of the Lewis & Clark Viaduct.
Design of the bridge began in 2012 and was completed in 2017, but weather-related challenges delayed construction in Phase 1. Major flooding and severe weather in 2019 forced construction in the river portion to shut down, with work on the river piers virtually impossible to complete due to high flood waters. Crews were unable to access pier sites in the Kansas River, preventing work from continuing on the upright piers of the structure. The flooding resulted in most of the possible workdays being lost in the spring of 2019.
Despite project delays in the river, the half-mile bridge replacement associated with Phase 1 is anticipated to be completed this year. Moving forward, and when funding is available, Phase 2 of the project is expected to replace the eastbound bridge, and a subsequent Phase 3 will add flyover ramps to carry westbound I-70 over the river.
Kevin Eisenbeis is director of bridges at Burns & McDonnell. In this role, he coordinates the firm’s bridge construction design work for contractors and serves as project engineer and principal designer on major projects. His experience includes design and preparation of construction plans for highway and railway projects, long-span steel and prestressed concrete structures, steel trusses, moveable bridges and many other facets of bridge construction and design.