Allegheny Township officials blame traffic light timing for backups into Route 356 roundabout

The roundabout where Route 356 meets La Belle Vue Road in Allegheny Township, completed in 2023, was meant to reduce crashes and congestion.

And while police say the safety gains are real, traffic improvements from the $7.7 million project haven’t quite met expectations.

Township officials have raised concerns to PennDOT about traffic backing up into the roundabout as drivers try to turn left from the northbound lane of Route 356 onto Melwood Road.

Making this turn requires a lull in opposing traffic or courtesy from other drivers, and can quickly congest the busy corridor.

The roundabout and subsequent intersection are key access points to many of the township’s businesses as well as Kiski Area High School and Kiski Area Intermediate School.

PennDOT Business Performance Manager Joel Morris told TribLive the agency is aware of short waits, which typically resolve within a cycle or two of nearby traffic signals, during peak travel times.

Township Supervisor Mike Korns said the issue isn’t restricted to morning and evening commutes, though.

He claimed to have seen traffic in the northbound lane of Route 356 on Sunday spilling into the roundabout, all caused by a single car attempting to make that fraught left turn.

Police Chief Dan Uncapher, chiming in at a supervisors meeting this week, added “we haven’t even gotten into some of the summertime events, such as graduation, which is always a disaster for that intersection.”

Township officials believe tweaking traffic light timing at the intersection will remedy the situation.

Though PennDOT apparently has been looped into the discussion, Morris said responsibility for the traffic signal was returned to Allegheny Township last year, leaving it to local officials to implement changes.

Despite township complaints — and surely some frustration from drivers — the consensus is that traffic is flowing much better than when a single stop sign governed the intersection.

Trucks would occasionally get stuck in the Alle-Kiski Valley’s first roundabout, causing delays, but PennDOT addressed that last year by widening the curb.

Not counting those incidents, Uncapher said his department has only responded to two crashes there, a decrease compared to the old design.

“The roundabout has definitely helped,” he said.

Uncapher’s observations are in line with a statewide study connecting roundabouts to 7% fewer crashes and 51% fewer crashes involving injuries.

For this particular one, Morris said, it’s too soon for PennDOT to declare mission accomplished on safety.