A set of temporary traffic lights is causing misery for St James residents as phase three of the Northampton smart corridor scheme begins.
Motorists have been using residential streets to get around the roadworks in Weedon Road, and it has even led to lorries trying to perform U-turns down Glasgow Street.
The residents' association has tried to arrange a crisis meeting with the county council's highways department, but have had no reply.
Residents have even suggested taking the law into their own hands and barricading the Scottish streets to stop the rat runners.
"They are using our streets because they aren't going to wait. The temporary lights don't work together and only let one or two cars through at a time," said Graham Croucher, chair of the St James residents association.
"One resident called me to say it took them fifteen minutes to get from the Thomas Beckett pub to Spencer Bridge Road - that's less than half a mile.
"We predicted this would happen long before the roadworks started, and this week has not disappointed.
"It will be even worse when the schools start up again after Easter."
Northamptonshire County Council began work on the Smart Corridor scheme in January, promising to relieve traffic flow and 'improve commuter journeys'.
The third and final phase of the works began on April 4 and saw a set of temporary traffic lights being installed in Weedon Road, by Beacon Bingo, and at Harlestone Road, while Spencer Bridge Road has also been closed off.
However, long queues and tailbacks have plagued Northampton motorists since the lights went up, especially at rush hour.
Mr Croucher said: "We've had lorries and buses using our residential streets to get around the roadworks.
"With Spencer Bridge Street closed off, motorists will just use the back roads as a rat run to get around the problem. It's only a matter of time until someone gets hurt down one of these roads.
"There are other problems. They've moved a pedestrian crossing up the road in St James Square. But the new one is too narrow. There's only room on there for one pushchair or mobility scooter. It's not safe.
"We've had very little communication from the highways department. We've written to them to discuss the dangers the works have caused but we have had no reply. We just want a working relationship."
Councillor Jill Hope, district councillor for Sixfields, said: "What difference is this going to make in the end anyway? They've adjusted some of the bus lanes to make them shorter and smoothed the road over. But with all these estates going up by the A45 and the potentially hundreds of cars that will bring it still won't help
"St James is a funnel for traffic coming from the west of the town. If just pour more and more in, but smooth the funnel a bit, it will still back up."
Councillor Hope had even hinted some residents are willing to stop the rat runners themselves by barricading their streets.
The Smart Corridor roadworks are scheduled to be completed by June.