Construction crews in Westfield have kicked off a long-planned project to send the Monon Trail under East 161st Street, giving walkers, runners and cyclists a way to avoid crossing heavy traffic at street level. City officials say the new tunnel is designed to cut down on collisions and make the route feel safer for families and daily commuters. During the buildout, trail users can expect detours and occasional lane restrictions as work continues through the year.
Project timeline and scope
According to the City of Westfield, work on the "Monon Tunnel" at 161st Street started on March 2, 2026, with the project listed as running through December 2026. The city’s construction page puts the estimated price tag at about $8,000,000 and notes that 161st Street is expected to stay open to cars while the trail is temporarily rerouted onto nearby streets. Officials say detours for trail users will generally send people along 156th Street, Oak Ridge Road and 169th Street during major work windows.
Why the tunnel is moving forward
City leaders point to years of near-misses and heavy traffic at the 161st Street crossing as the main reasons this underpass is finally happening. A traffic study found that about 14,000 vehicles use 161st Street each day, and the tunnel is set to replace the signalized HAWK crosswalk that went in back in 2021. "We are moving forward at least initially with local funding," Westfield Director of Public Works John Nail told IBJ.
Short-term safety fixes
Before money came together for the tunnel, the city tried to calm things down at the crossing with interim safety tweaks, including flashing lights around stop signs and a HAWK signal meant to grab drivers’ attention as they approached the trail. Local coverage has documented multiple crashes at the site over recent years. WRTV reported nine accidents at the crossing since 2016 and quoted residents who described the spot as "scary" when traffic is heavy. Patrols and public reminders to stop at the trail crossing remain in place while construction moves ahead.
How the work will affect trail users
During major phases of construction, the Monon Trail will be pushed around the work zone, with the city directing people onto nearby streets. The project page from the City of Westfield lists detours that steer riders and walkers toward 156th Street, Oak Ridge Road and 169th Street while crews build the underpass. Trail users should expect posted signs and temporary barriers along the detour routes, and officials say the plan is to keep 161st Street open to drivers while limiting the hassle for people on the trail as much as possible.
Funding and what's next
The tunnel has been in the works for years, with design stretching back well before shovels hit the ground. One key step was clearing a utility conflict that stood in the way. YouAreCurrent reported that in March 2025, the Board of Public Works signed off on about $1.1 million in reimbursements so Citizens Energy Group could relocate a water main that clashed with the tunnel alignment. Westfield officials have said they will keep chasing grant opportunities but are proceeding with local funding for now, as reported by IBJ.
What residents should know
City leaders say the goal is to maintain traffic flow on 161st Street while giving the Monon Trail a safer, grade-separated crossing. Residents and trail regulars are urged to watch for updated detour maps and construction notices from the city as work progresses. Officials advise planning extra time, considering alternate routes and staying alert for intermittent lane restrictions whenever crews are on site.
