Roadworks on Castlegate, Newark, are on course to be completed by Friday, allowing for the one-way system to be removed.
It would mean the route was open in time for Newark Festival.
The road has been one-way since February as part of Severn Trent’s £60m investment to improve the town’s water and waste services, which will see more than 400 homes and businesses protected from sewer flooding by 2020.
Mr Nick Wallace, of Severn Trent, said: "We are very aware that the festival is looming but things are looking good for us hitting the completion date for the one-way system.
"With more to be done, it is obviously hard for us to be absolutely certain but we are working hard to get everything done and get the traffic flowing.
"We know how disruptive work like this can be and we are as keen as anyone to get things back to normal in Castlegate."
The three-day Newark Festival is at Riverside Park from Friday, when large crowds are expected.
Recently, The Siege Breaker, a state-of-the-art tunnel boring machine, completed its nine-month journey underground.
It created a 3km tunnel, big enough to drive a Transit van through, which will allow for the much-needed bigger and better sewers to be installed.
The one-way system often resulted in long queues on Sherwood Avenue and Queens Road, and town centre businesses reported a drop in trade.
Severn Trent will continue to run its shuttle bus around the town up to the end of Saturday, so festival visitors can use it.
The bus, free for anyone to use when visiting the town, aimed to help keep businesses open during the work.
Normal bus services will resume from Monday, June 18.
The return to full use of Castlegate will also see the removal of temporary barriers that were installed to prevent Cartergate and Baldertongate being used as a rat-run to avoid part of the one-way system.
The barriers were introduced into the pedestrianised area to safeguard people.
Although work is expected to be completed on Castlegate, it will continue in other parts of the town.