Motorists are being alerted about potential disruption in Selsey later this month.
Construction is due to start in Chichester Road on the entrance of the new ASDA car park.
Work begins on Monday, February 13 and is set to last for 11 weeks.
Construction company RG Group will also make alterations to the Manor Road/Chichester Road roundabout and widen the road.
Manor Road will close northbound during the works.
This will create a one-way system for traffic to follow through the roadworks.
Temporary traffic signals will be in place for the last five weeks of the construction.
The signals will be manually operated at peak times.
All work is carried out between 8am and 6pm.
No work takes place at weekends.
West Sussex County Council will monitor the work and the flow of traffic.
RG Group spokesman Craig Goodison said: “RG Group has vast experience in completing projects of this nature.
“The necessary alterations to the road will improve access in and around the local area and every measure will be taken to ensure disruption is well managed and kept to a minimum.
“The benefits the new development will bring to Selsey long term are enormous and will provide an important boost to the area once completed.”