Located in the heart of downtown Indianapolis, the North Split is where I-65 and I-70 meet. Also coined the Crossroads of America, it is the most heavily traveled interchange in central Indiana, serving 220,000 motorists each day.

In support of a plan to improve statewide and regional safety and mobility, HNTB helped INDOT reconstruct this critical, three-level interchange. The project’s work included 5 miles of interstate reconstruction, complete reconfiguration of the three-leg system-level interchange, upgrades to integral entrance and exit ramps, and interchange operations improvements. The redesigned interchange improves safety by eliminating weaving and merging, leading to better traffic flow. The new system takes up a smaller footprint and increases the walkability of surrounding downtown neighborhoods.

One Project, 50 Bridges

As part project's scope of work, bridge condition ratings proved to be the gateway to a key component of the project — the reconstruction and replacement of 50 total bridges. With lengths ranging from 60 to 1,250 feet, the bridges traverse local roadways, ramps and other infrastructure, making their construction a complex aspect of the project.

Ensuring a Successful Delivery

HNTB served as preliminary design and environmental lead and later transitioned to design-build technical procurement advisor. In this advisory role, the firm developed the design-build, best-value procurement documents and review and support services for the public-private agreement process. Following selection, the firm provided design and construction oversight of the design-build contractor on INDOT’s behalf. Responsibilities included monitoring design and construction to ensure contract compliance, quality audits, construction scheduling and estimate reviews, public outreach and communication, and traffic management oversight.

To further support INDOT’s goals for the project, HNTB also introduced a virtual public involvement office and the use of aerial drone photography to monitor construction progress, check production rates and capture project images.

With an innovative design that reduces points of conflict and encourages a more free-flowing traffic pattern, the North Split interchange improvements have transformed safety and mobility for the region and the state.

Location: Indianapolis, IN

Client: Indiana Department of Transportation (INDOT)

Services: Technical procurement advisory, NEPA documentation, preliminary engineering, procurement services, design oversight, construction oversight

Awards: 2024 Honor Award, ACEC Indiana