Oklahoma’s I-40 is the primary east-west route for the state. In Oklahoma City, this same interstate highway includes the aging Crosstown Expressway that provides arterial access to the downtown area, along with Tinker Air Force base.
Ten years of planning and preparation by the Oklahoma Department of Transportation (ODOT), along with state, federal and local communities have resulted in the largest highway project in Oklahoma history.
When completed in 2008, the current elevated portion of I-40 that skirts downtown Oklahoma City will be relocated approximately five blocks to the south. Gone will be the 8,888 ft. (2,709 m) twin bridges, replaced by ten-lane 4.5 mi. (7.2 km) expressway.
The existing elevated bridge was built in the early 1960’s and has long exceeded its design life. Substructure deterioration including exposed reinforcing steel, leaking deck joints and missing bolts from the bridge’s steel girder section required ODOT safety inspections every 6 months.
ODOT originally reviewed various plans for improving this highway’s infrastructure and safety. Factors involved in the analysis not only included the urban core of Oklahoma City but also two Class I railroads, the Burlington Northern Santa Fe (BNSF) and the Union Pacific (UP). After much analysis and consideration it was decided to move the new corridor through an existing railroad corridor to the south.
What makes this project unique is that it is a complete realignment of an interstate highway within an urban setting. According to Taylor Henderson, Crosstown Expressway Construction Coordinator, “Since there are no traffic issues in using this plan, it is possible to let projects concurrently. This process accelerated our overall completion date by several years.”
Additionally, this plan preserves both north-south and east-west rail corridors and virtually eliminates any rail delays.
The new highway will be constructed either at grade or depressed grade thus eliminating future issues regarding bridge maintenance.
The existing I-40 highway will not be removed but eventually will be replaced by an at-grade boulevard from Western Avenue to the west of Walker Avenue.
The project’s intent is to provide motorists a conduit to Oklahoma City’s downtown area. Henderson said that it would take between two and five projects to convert the old interstate into a business boulevard. Including the demolition of the existing bridge, the project is scheduled for completion in June, 2009. Oklahoma County Association of County Commissioners plans to reuse the old bridge beams for other applications.
The project includes more than $20 million in railroad improvements. This is the largest rail project in ODOT history. The previous merger of the Burlington Northern and the Santa Fe made this ODOT plan feasible.
The project will replace a BNSF line that overlaps the new highway right of way. This line will be moved to an existing track south of the North Canadian River.
According to John Bowman, project development engineer for ODOT, two contracts were awarded to Muskogee Bridge Company of Muskogee, Okla., to construct two permanent highway bridges and BNSF railroad bridge spanning the historic canal. The second contract involves the construction of a temporary bridge adjacent to an existing UP railroad bridge.
According to Bowman, the structure spanning the canal consists of a post-tensioned box girder with a rigid frame substructure.
Bowman stated that the second project calls for the construction of a temporary shoo-fly bridge. Once railroad traffic moves to the shoo-fly bridge, the old structure will be demolished and the new bridge built in its place. Bowman indicated that the new bridge will use a 16 ft. (4.88 m) plate girder beam. ODOT has provided financial incentives of $173,000 per day for the early completion of this project.
The project is financed through a combination of federal and local funding. ODOT Director of Preconstruction David Streb stated that federal earmarks ran through the Transportation Equity Act for the 21st Century (TEA-21).
“We have established an eight-year work plan to ensure that there is enough funding to complete the freeway and the boulevard upgrades,” Streb said.
Streb added that funding including a $49 million earmark is available through 2010. In most cases, funding formulas will require a 10 percent matching funding from the state.
According to Bowman, the entire project will cost $557 million, the largest in ODOT history. It will incorporate 21 different projects most operating concurrently to expedite the completion timeline.
The projects call for 1.7 million cu. yds. (1.2 million cu m) of unclassified excavation to be moved, to prepare for pavement and bridge structures. Utility reconstruction will include multiple fiber optic relocations, overhead electric transmission lines and a 60 in. (152.4 cm) sanitary sewer line under the Bricktown Canal.
The completed expressway will have ten lanes, three local and two express in each direction with 580,000 cu. yds. (443,442 cu m) of dow-jointed concrete placed in 11.5 in. (29.2 cm) thickness. The pavement will have a 30-year life expectancy. The project has a design life of 50 years. When completed, the construction will be able to accommodate 173,000 vehicles per day.
Eleven crossing bridges will be constructed in the new interstate. They will be constructed with box-girder beams utilizing vertical abutments. Once completed, 37 new bridges will be constructed which includes 1 million sq. ft. (92,903 sq m) of bridge deck.
Cast-in-place concrete utilizing mechanically stabilized earth will be placed on the below ground portion of the interstate retaining walls. At present, ODOT has identified two sites in the right-of-way that will require environmental mitigation.
Additional enhancements include a park, pedestrian bridge and the appropriate sound walls. Bridges, form liners and pylons along the corridor will have their own individual aesthetic treatment. CEG