The parking structure under Grant Park has 1,300 spaces and was constructed in 1963. The structure has concrete floor slabs supported by concrete columns and walls. Investigations revealed structural deterioration. Mechanical, electrical, plumbing and other systems were also deteriorated due to age. Due to the deterioration, along with building code changes, fire sprinkler requirements, and other changes to codes or laws (ADA), the structure was in great need of updates and repairs.
Walker created a plan for repairs that included:
- Full-depth concrete replacement
- Mechanical, electrical, plumbing system upgrades
- New elevator connects the three underground parking levels to the street level
- Reconstructed north entrance to underground garage
- Wide pedestrian walkways isolated from primary vehicle circulation and turns
