(Photo by Gwen Sour) The intersection at Fourth and Marion streets, shown Monday, remains closed due to construction to repair a sinkhole.

Work on the large sinkhole at Fourth and Marion streets is moving closer to completion after months of delays caused by weather and unexpected complications underground.

Marietta City Councilman Bill Gossett, chairman of the Streets and Transportation Committee, said the project revealed significant damage beneath the surface. What began as a sinkhole repair evolved into the replacement of more than 200 feet of storm drain, originally constructed with sandstone in the mid-to-late 1800s.

“The mortar had fallen out between the sandstone, and in some cases, keystones had dropped,” Gossett said. “Once that starts happening, the system collapses. The integrity was so degraded we had to replace it all.”

The repair began in June and was originally expected to wrap up in late summer. Crews encountered repeated setbacks as heavy rains washed away the limestone base needed to set new precast box culverts. Each culvert section required careful placement and backfilling before installation could continue.

Gossett said contractors also discovered a section previously reinforced with a sprayed-on concrete lining known as gunite. Removing that material was more difficult than anticipated and added to the project’s timeline.

Mayor Josh Schlicher said crews have battled more than just the weather. Utility lines — including fiber optic and phone cables — ran directly through the site, forcing workers to navigate around sensitive infrastructure. He said crews also had to remove reinforced concrete lining in parts of the old culvert, which took longer to dismantle than the original sandstone.

“Every time it rains, they can’t work because it has to drain, and it may take two or three days before the flows drop low enough,” Schlicher said. “But by the end of this week, the culvert itself should be connected. Then it’s backfilling, restoring the water and sewer lines, adding storm drains, and finally rebuilding the road.”

Schichler said the final phase will include new curbing, sidewalks, and pavement. With the nearby building now removed, the city is also widening the intersection to provide smoother access to Fulton Street. Schlicher estimated the entire project will be wrapped up by the end of October.

The work is being carried out by Jimmie Harper Construction and is estimated to cost about $620,000, below the $650,000 originally authorized by council.

Gossett acknowledged the extended closure has been frustrating for residents, especially those traveling to and from nearby Marietta Memorial Hospital. But he noted the work was unavoidable.

“It’s been a real inconvenience, but this is one of those things that had to be done,” he said. “Unfortunately, we’ve had other sinkholes appear in town, and much of the underground drainage hasn’t been looked at for decades.”

In addition to the work on Fourth and Marion, Schlicher said another sinkhole near the wastewater treatment plant, which has closed part of the River Trail, is also being addressed. Crews are expected to finish repairs there by mid-September, allowing the trail to reopen.

City officials have begun preliminary discussions about how to address the broader stormwater system in the future, but the high cost of surveying and repairs remains a challenge.