The A378 Langport Road will be closed for five weeks over the summer holidays for essential drainage improvements.
The section of the road between Wrantage and Fivehead, known locally as Mile Hill, has been susceptible to flooding in recent times with surface water on the carriageway during times of bad weather.
Work is due to start on Monday 31 July with teams laying around 300m of new pipes and building new drains and gullies to help the water drain away faster. This will also allow for resurfacing to take place at a later date.
Cllr John Woodman, Somerset County Council’s Cabinet Member for Highways, said: “We know there’s a problem with flooding here and I’m pleased we’ve been able to plan a comprehensive solution.
“Closing the road is always a last resort, but drainage work requires deep excavations across the highway and a closure is the best way to keep both workers and members of the public safe.
“We’ve planned this work for the school holidays when roads are generally quieter and I know the teams will be working hard to get the job done as quickly as possible.”
A signed diversion route suitable for all vehicles will be in place but, as with any closure, local drivers are free to find their own alternatives.
Stay up to date with the latest on the roads by following @TravelSomerset on Twitter or visit www.travelsomerset.co.uk to find out about current and future planned roadworks.