Department of Transportation

Preliminary Staging

The new interchange is planned to be built in stages in order to minimize impact to traffic operations. Except for the ramps that are planned to be permanently closed, the current traffic circulation and existing connections of the interchange will remain open throughout construction. The existing two lanes on Route 280 will be open in both directions at most times, and three lanes on Route 21 will be open in both directions.

Stage 1 - Completed
Construction will begin with sidewalk improvements, utility relocations and signal replacements on Grant, Spring and Broad Streets, and the ramp connecting Route 21 to Spring Street. Stage 1 will also build the temporary signals and temporary jug handle on Route 21. This jug handle will be used in the following stages to maintain some of the existing ramp movements within the interchange throughout construction.
stage 1 map
Stage 1 (pdf 1.4m)

Stage 2 - Completed
In this stage a major readjustment of the interchange ramps will take place for the remainder of the project. This includes the permanent closure of the Route 280 westbound ramps to Grant Street and to State Street which will be at the beginning of this stage. Movements that will remain but rerouted through the temporary signals and jug handles are Route 280 westbound to Route 21 southbound and Route 21 southbound to Route 280 eastbound. A move that will not be affected is Route 280 eastbound to Route 21 southbound. Ramps to be closed for construction, but rerouted through detours are the Broad Street to Route 280 eastbound ramp and the Route 21 northbound ramp to Route 280 eastbound.

Stage 2 construction activities will concentrate on the construction portions to the outside of Route 280 along with associated ramps and the construction of temporary walls and roadways for the next stage. Construction of temporary walls over the ramp alignments will allow Route 280 to be operational in Stage 3. Another major item in Stage 2 is the re-decking of the Route 280 Bridge over Martin Luther King Boulevard. Due to tight constraints, Route 280 will need to be reduced to one lane in each direction for two weekends to accomplish this complex construction.

stage 2 map
Stage 2 (pdf 1.4m)

Stage 3 - Completed
Route 280 and Route 21 mainline traffic will remain as well as the majority of the interchange movements. The Route 280 traffic will be shifted onto the temporary Route 280 highway built on the temporary walls and the footprint of future ramps to the outside of the current Route 280. Stage 3 will mainly consist of the reconstruction of the inner portions of Route 280. The new Route 280 bridges over Route 21 and other ramps will be constructed and the remaining existing bridges in between will be torn down and replaced with roadway embankment. While all this work is being performed, the complex re-decking of the Broad Street Bridge will be taking place during Stages 2, 3 and 4.
stage 3 map
Stage 3 (pdf 1.1m)

Stage 4
Route 280 traffic will be shifted to the newly built Route 280 and the temporary walls will be torn down. A new ramp jug handle connecting Route 21 northbound to Route 280 will be constructed in place of the old ramps under the Stickel Bridge. The final configurations of the remaining entrance ramps to Route 280 will be completed to allow all movements at the interchange.
stage 4a map
Stage 4a (pdf 1.2m)
stage 4b map
Stage 4b (pdf 1.4m)

Last updated date: October 21, 2020 4:02 PM