Drivers are being urged to avoid the Tavistock Street area in Bedford for 14 weeks as the road is closed for major repairs.
Repeated flooding of nearby homes and businesses means a new drainage system is needed, while the road layout will be improved between Peel Street and the Harpur Street/Broadway junction.
The work will begin on Monday, February 22, with diversions in place along Union Street, Bromham Road and Harpur Street for traffic using Tavistock Street to head through the town.
A council spokeswoman said the road needs to be completely rebuilt and resurfaced along with the construction of a new drainage system, which should removing the need for ongoing maintenance and regular pothole repair.
New energy efficient LED traffic signals and LED street lights will also be installed.
Cllr Charles Royden, Portfolio Holder for the Environment and Transport, said: “As a result of the total lack of drainage in this area of Tavistock Street the structure of the road has been severely weakened and flooding remains a major blight for those living and working locally.
“This is a safety issue requiring urgent work now to prevent damage to properties in the area and to avoid the possibility of a more serious carriageway failure in the future. This is one of our major town centre roads, which is heavily used by motorists and pedestrians so we have to get these repairs done and done properly.”
He added: “I urge drivers to avoid the area if at all possible and follow the signed diversion routes which we are putting in place to reduce disruption.”