Jun 3, 2026 By Mike Jones 2 min read

The big dig is about to begin in Washington.

The state Department of Transportation is closing Route 18 at South Main Street starting Monday as construction crews will begin replacing the box culvert that allows traffic to pass over Catfish Creek near Cameron Stadium.

The closure for that section of Route 18, which is also known as Park Avenue, is expected to last three weeks until June 29 while the pre-constructed culvert is installed and the road is rebuilt.

The existing culvert, which was built in 1928, will be removed and replaced with a new reinforced concrete box culvert, which local and state officials have said they hope will improve conditions at the notoriously flood-prone intersection.

In addition to replacing the culvert and repaving the roadways, PennDOT said the concrete curb, sidewalk and gutters will also be replaced in that area.

Once the three-week closure is completed for the work underneath Route 18, workers will then shut down South Main Street at that intersection for 20 weeks as construction on the rest of the box culvert continues until mid-September.

PennDOT is directing vehicles to use a nearly 5-mile detour, looping around the area by taking Park Avenue to Franklin Farms Road to West Chestnut Street to Jefferson Avenue to West Maiden Street back to South Main Street.

“We will have ‘Road Closed, Local Traffic Only’ signs with arrows identifying the detour placed in both phases, as well as detour signs with route markers and arrows placed along the route,” PennDOT District 12 spokeswoman Melissa Maczko said in an emailed statement.

Over the past few weeks, crews have been performing other prep work in the area, shutting down one lane of both Route 18 and South Main Street and directing traffic through with flaggers.

Crews have been working in the area since the fall, when South Main Street was closed for more than a month while workers relocated some of the underground utilities that were in the way of the construction zone.