It took more than 60 years for the Allegheny County portion of the Mon-Fayette Expressway to go from an idea to actual construction, but that first year of construction in Jefferson Hills started with a flourish:

  • 4 million cubic yards of dirt moved to build the interchange at Route 51 and the first 3½ miles of toll road.
  • A series of supports built for six sets of bridges.
  • 1,000 feet of drainage pipe — 72 inches in circumference and 14 inches thick — installed with a creek stream relocation along Miller Road.
  • Another stream relocation north of Jefferson Boulevard to clear room for bridge supports.
  • Dozens of acres cleared along Camp Hollow Road in West Mifflin so that work can begin early next year on the second stretch of construction.

“In one season, we got a lot of work done,” said Craig White, senior associate with Johnson, Mirmiran & Thompson Inc. who is overseeing construction for the Pennsylvania Turnpike.

“We have had really good weather. They have been working four 10-hour shifts. It seems like it only rains on Fridays.”

Long time coming

Anyone who’s been around Western Pennsylvania for a while has heard about plans for the Mon-Fayette Expressway extension, which has been on the drawing board since the 1960s. Back then, steel was still king in the Monongahela River Valley, and nearby residents could tell the time of day by the sky lit red from molten steel.

That includes White, whose early career had him working for Dick Corp. on Route 51 and driving through the area nearly every day. As he led a tour earlier this month through the construction zone, he sprinkled the talk about the new highway with memories of small local roads that were popular shortcuts for locals that have been temporarily or permanently eliminated by this project.

After a series of starts and stops and redesigns, the turnpike awarded the first construction contract in January. Trumbull Corp. won the $214 million project to build a 3.1-mile stretch from Route 51 to Coal Valley Road in Jefferson Hills.

The state Legislature assigned the turnpike the task of building the highway using a portion of the revenue generated by the state’s oil franchise tax. It has awarded contracts for the first two segments and expects to build the southern wing to Route 837 in Duquesne by the end of the decade at a cost estimated at $1.3 billion.

Design of the northern section, which would carry the highway to the Parkway East in Monroeville, is on hold until the agency is sure it has the money to pay for it.

Crews place reinforcement bars on Tuesday, Dec. 12, 2023, as they begin construction of the pad that will support a pier for the new Route 885 bridge over the Mon-Fayette Expressway in Jefferson Hills. (Ed Blazina/Pittsburgh Union Progress)

Crews began clearing the land to make room for the highway last spring. That included permanently closing a 1-mile section of Miller Road between routes 885 and 837 and creating cul-de-sacs on each end.

To save money, designers do all they can to move the 4 million cubic yards of dirt to other locations on the site rather than paying to haul away. Some is used to fill in valleys, and some is used to create attractive mounds surrounding the highway.

“We have excess material everywhere,” White said. “We’d rather have that than have to go find it someplace when we need it.”

This year was mostly preparation work — preparing the land and installing five sediment detention ponds to prevent flooding during and after construction, relocating two streams, and building supports for ramps at the key interchange with Route 51. Even before actual road construction, the turnpike paid more than $50 million for Duquesne Light to relocate major power transmission lines that were in the path of the future highway, resulting in 67 new towers from 65 feet to 190 feet tall.

“Just where the road is going to go has been the biggest challenge,” said John Dzurko, the turnpike’s construction manager on the project.

Much of the area sits above the Pittsburgh coal seam, which means the area is dotted with old deep and strip mines. Crews haven’t found any real surprises, but one old mine has so much water in it that they will have to install a huge retaining wall to hold it back so it drains away from the new road.

Weather conditions were so favorable that crews poured the deck for a bridge above Jefferson Boulevard in early December, something White said rarely happens in this region.

When the winter weather breaks, crews expect to have steel beams ready to begin assembling the framework for decks on other bridges. That will include the tricky ramps at the interchange with Route 51 and Route 43, the original part of the expressway that begins at Route 68 near Cheat Lake in West Virginia.

“We’re building two big bridges between two other big bridges,“ Dzurko said.

Right now, the southbound ramp from Route 51 to Route 43 is closed. When the new expressway connection nearby is finished next year, the southbound ramp will reopen but the northbound side will be closed for construction of the new connection on that side.

Installing the drainage between Miller Road and Route 837 was another complicated process. That’s because the pipes were so heavy — 8-foot sections that weighed 16 tons each — that they had to be delivered one at a time.

This series of piers will support ramps to connect the new Mon-Fayette Expressway to Route 51 in Jefferson Hills.

Moving ahead

Trumbull also got the second contract for the toll road in October, $165.6 million for the section from Coal Valley Road in Jefferson to north of Camp Hollow Road near Curry Hollow Road in West Mifflin.

Crews used the end of the year to clear trees and brush from the area beside Camp Hollow so they can hit the ground running in the spring.

That’s the curse and blessing of building a completely new road, White said. It involves extended time clearing the path, but there’s no traffic to contend with, and the site if ready, crews can proceed unimpeded.

“Building a new road, you usually don’t have to worry about what to do with the traffic,” White said.

At some point next year, contractors will install their own temporary concrete production plant at the site. That will allow them to produce the thousands of yards they need on location, cutting down travel costs and allowing for better temperature and moisture control of the batches.

The project will use long-life concrete, a relatively new mixture of stones, sand and cement first used by the turnpike five years ago on the Southern Beltway near Pittsburgh International Airport. The concrete should last at least 40 years and perhaps substantially longer, compared to 26 to 30 years for traditional concrete.

White and Dzurko said the turnpike made some tweaks in the specifications based on what the agency learned on the previous project, so the agency is hoping for even better results.

Motorists can expect a few traffic disruptions from the project in the coming year. Part of Coal Valley Road that has been closed for excavation will reopen in March, but part of New England Road in West Mifflin will close in the spring.

The first two sections of the expressway are expected to be finished enough to open in late 2026.

Trumbull Corp. workers install Fabian baskets to control erosion under a new bridge that will carry Route 885 above the Mon-Fayette Expressway in Jefferson Hills on Tuesday, Dec. 12, 2023. (Ed Blazina/Pittsburgh Union Progress)
Ed Blazina

Ed covers transportation at the Pittsburgh Post-Gazette, but he's currently on strike. Email him at

Ed Blazina

Ed covers transportation at the Pittsburgh Post-Gazette, but he's currently on strike. Email him at