Traffic is building even before 4 p.m. when rush hour officially starts.

Southbound traffic approaching Bethlehem’s century-old Hill-to-Hill Bridge stacks in the right lane well before the Third Avenue entrance. Cars and trucks whiz by in the parallel left lane, queuing later for a left turn, east onto the city’s Southside. A few will cut between cars traveling in the right lane; a smaller number even drive straight under the light at Brighton Street.

And so it has gone for almost a century, when far, far fewer than theestimated 55,000 vehicles crossed the Lehigh River daily.

As built, the massive bridge once connected the North, West and South sides, until Route 378 replaced a roundabout, pushing northward.

Once again, though, the bridge will change.

With $98 million in funding secured through 2029, PennDOT hopes to complete the project as early as 2027 – the bulk of the cost covered using federal funds. Both such estimates likely will change when final plans are drafted and bids for construction are received.

“It’s a big project,” said regional PennDOT spokesperson Ron Young.

Among bridge work, first outlined in draft form two years ago as plan 5B: From West Third Street, a new partial southbound span would end at a merge point with other southbound traffic past the first existing truss.

Lanes on the bridge would widen, Young said, though details await final plans.

A “multiuse trail,” flanking the bridge’s eastern edge, is projected to serve as many as 350 pedestrians daily as well as 100 others “walking their bicycles.” (During Musicfest, those numbers skyrocket.)

The ramp connecting the bridge to Main Street would remain, as would the barricaded spur from Spring Street. Planners did consider opening the latter but decided this would not improve southbound traffic flow significantly.

Overall sidewalks to the west and east would remain as would two lanes in opposing directions, Young said.

Initially, bridge planners weighed four options before favoring the partial east side span. No change made no sense, and construction of a full parallel span to the east would, among many concerns, have forced demolition of the Fritch Fuel sign and silos, a registered federal landmark.

As much as possible, planners said, construction work would not block all traffic lanes entirely during peak traffic period. Instead lane restrictions would occur off-peak, such as on weekends and overnight. At one point, though, such as for the northbound ramp onto Main Street, work is expected to force a complete closure lasting several weeks.

Overall, bridge planners foresee significant improvements, though a significant chokepoint does remain south of the bridge at Five Points - outside the scope of the project.

Southbound traffic that exits the bridge onto two lanes must funnel into a single lane there to travel over South Mountain. Many drivers from a turning lane for Broadway instead accelerate to merge left once inside the intersection. Cyclists sharing the current six-foot-wide walkways ride, rather than dismount, and now lacking bells, often overtake pedestrians at speed without warning. Electric bikes now can travel at 28 miles per hour and, in Pennsylvania, are not allowed on sidewalks.

Also unanswered, speed. Drivers southbound widely ignore the posted 30 mile-per-hour limit at speeds, off-peak when lanes are clear, that can reach 60 miles-per-hour or higher. Speeds northbound also exceed limits before the Main Street turnoff.

In March, the state made permanent use of automatic speed cameras in Pennsylvania Turnpike work zones. Drivers exceeding the posted speed by 11 miles per hour initially would be mailed a warning, then successive fines of $75 and $150. At this point, motorists would not have operating licenses suspended.

Philadelphia has been allowed such cameras on dangerous Roosevelt Boulevard. It reports a cuts in speeding of 95 percent.

A traffic-bureau representative at the Bethlehem City Police Department, explained once that enforcement efforts on the current narrow roadway risked causing accidents.

Bethlehem Police Chief Michelle Kott said radar would help, but that the state does not allow its use by city police.

“Speeding has consistently been the number one complaint my department receives,” she says. “I would urge residents with concerns to contact their state representatives to advocate for the use of radar by local law enforcement.”

State Sen. Lisa Boscola has voted to lift the radar restriction several times, though it failed in the House, a representative said. Jeanne McNeill, who represents Bethlehem‘s East Side in the House, said she would support allowing radar if her chairman agrees.

The Lehigh Valley Planning Commission will vote June 27 on this project and several others, including $57 million for improvements to the interchange of Route 309 and Center Valley Parkway.