Work is being carried out next year so cyclists can have a safer journey through Bersted, according to the county council.
The existing footpath on the southern side of Rowan Way is being widened to accommodate cyclists and pedestrians.
West Sussex County Council is building the path so cyclists avoid using the North Bersted Relief Road, which will become busier when the Felpham By-Pass opens on March 4.
The new path, 0.6 miles in length, connects North Bersted Street to the A29.
Construction will take place in two stages:
Rowan Way (A29 to the Rowan Way roundabout)
Work starts week commencing Monday, January 4 for up to eight weeks, subject to weather.
New pedestrian island built west of The Peel Retail Park entrance.
Rowan Way (Rowan Way roundabout to North Bersted Street)
Work starts from Monday, March 7 for up to eight weeks, subject to weather.
New pedestrian islands built east of the Addison Way junction and the Sunningdale Gardens junction.
All work will take place between 7.30am and 4pm.
Two-way traffic will be maintained during construction.
No diversion route is necessary.
County Council Cabinet Member for Highways and Transport, John O’Brien, said: “We are pleased to be building this widened cycleway.
“It will make travel safer for people on bikes and mobility scooters in this part of Bersted.
“The first phase needs to be done before the new relief road opens.
“Then we can concentrate on the second phase away from traffic using the bypass.”