The four-month closure of one of the main routes into Blackpool begins next week to allow a £4m repair project to take place.
Yeadon Way will be shut until the end of March to enable upgrade work to be done.
For traffic arriving from the M55 a clearly signed diversion route will be in place from the end of Yeadon Way via Progress Way, Squires Gate Lane and Lytham Road.
By following the signs drivers will arrive back at the end of Yeadon Way that leads to the main car parks and town centre.
Experts believe Yeadon Way could collapse in the next few years without the repair work taking place.
The road, which opened in 1986 and carries seven million cars a year, was built on the former railway embankment leading to the old Central Station. The three kilometre route includes five bridges, some of which have suffered severe cracking.
Thousands of metres of watercourses and hundreds of gullies alongside Yeadon Way are now being cleared.
Over the years, some of the drainage systems have become blocked or overgrown, meaning rainwater falling in the area was slow to run away into flood plains or sewers.
In total, 5,636m of watercourses and 2,232m of highway sewers are being cleared.
The work has also opened up a number of overgrown public rights of way that local residents can now use again.
One of the rights of way cleared as part of the work is at the back of Bridge Farm allotments, providing a new entrance for visitors.
Jean Hudson, secretary of the Bridge Farm allotments, said: “Our tenants on the watercourse side have had a constant struggle with flooding last few season before the work was done.
“Most of them could not grow anything; vegetables were rotting in the ground and the water even penetrated the greenhouses making them unusable.
The drainage work will also help to protect the future structure of Yeadon Way.
Previously, water that wasn’t able to drain away made the ground near the old embankment softer and as a result loosened the structure of the overpass.
These drainage works will help to make the ground sturdier, which, along with the repair works being carried out on other parts of the road’s structure.
Coun John Jones, Blackpool Council’s cabinet member for highways and transport, said: “This is an excellent piece of work to help protect properties in the area from potential flooding, as well as helping to secure the structure of Yeadon Way.
“We’ve taken a really hands on role in clearing these watercourses and are removing a backlog of silt and sediment that had built up over the years.
“The impact on the houses, businesses and green spaces nearby will be massive, and it will reduce the amount of times that back gardens overflow, allotments are underwater or when local football pitches are flooded.
“As is normal with watercourses, they pass through both public and private land but we’ve been able to work with the landowners to make sure that it isn’t a problem, and that we can get the job done efficiently.”