Walking along Canal Street, you might not be able to tell it, but a construction project under your feet is about halfway finished.

Workers are building a tunnel within a tunnel, coating the inside of a 200-year-old brick tunnel under Canal Street with steel bars and concrete.

The project kicked off in December and is projected to be finished sometime this fall.

The aim of the project is to keep the tunnel, not designed for a world with tractor-trailers, from collapsing in places as it has in the past, City Engineer David Gardner said.

“We’re still inside the canal, putting the steel bars up and putting the concrete liner on the inside of the brick,” Gardner said.

Work started near Southwest Distributors and will finish near the antebellum house Rosalie.

“We haven’t gone all the way to the end, but we’re getting there,” Gardner said. “It’s hard to see the progress because they’re underground.”

Work on the canal has become more visible to the surface world recently, though. Workers started Tuesday replacing a short metal pipe inside the canal with a concrete culvert that will support the heavy tractor -trailers delivering to the distributing company.

“A lot more will be visible now,” Gardner said. “We’re going to start working on the sidewalk and curbs, replacing the broken sidewalk. Later on, we plan on overlaying Canal Street, too.”

The work on the canal that runs the length of Canal Street is the first of a two-step project. After the canal is sturdier, work will begin on the drainage system in north Natchez, directing runoff to the newly refurbished tunnel.

Officials hope the project will improve drainage in the northern parts of town and prevent flooding.

The $3 million project is being entirely funded through he U.S. Army Corps of Engineers and the Mississippi Department of Transportation.