Buses will be unable to serve Halnaker, Boxgrove and Tangmere Aviation Museum during a four-week service diversion, Stagecoach has advised.
According to a service update on Stagecoach's website, Stane Street, Westhampnett will be closed from March 11 until April 4.
It added: "Stagecoach are currently running a diversion on route 55 between Chichester and Tangmere, due to works by Portsmouth Water in the Westhampnett area.
"The closure is necessary in order to lay water mains for a new housing development."
A Stagecoach spokesman said buses, during the course of the closure, will be unable to serve Halnaker, Boxgrove and Tangmere Aviation Museum
It added: "Buses will run normal route between Chichester & Stane Street (Crossroads) near to the Rolls Royce plant in both directions.
"Between Stane Street and Tangmere buses will divert via the A27.
"Unfortunately, to ensure a reliable route and timetable, buses will be unable to serve Halnaker, Boxgrove and Tangmere Aviation Museum throughout the duration of the road closure. A temporary timetable will also be in operation."
Halnaker and Boxgrove customers are advised by the bus company to use alternative stops located at Meadow Way (Hawker Close) or the Esso service station.
"Customers who would usually board at Tangmere Aviation Museum and Copper Beech Drive should use the alternative stop located at Meadow Way (Tamar Way)," the spokesman said.
"We apologise for the inconvenience this temporary disruption will have to travel plans for those affected by these works."