The Arun Valley railway line, linking Arundel and Crawley's Three Bridges stations via Horsham, is closing for nine days starting on Saturday (August 14).
Network Rail, the track-owning company, said it's to enable more reliable journeys, and some station improvements.
A spokesperson added that the improvement project as a whole, encompassing work beyond this weekend's closure, has recently benefited from an extra investment of £5m.
For nine days, from Saturday 14 - Sunday 22 August, no trains will go via Horsham.
These days will be followed by a weekend closure between 4th and 5th September, and a day closure on Sunday 3rd October.
Buses will replace trains along much of the Arun Valley line, from Arundel and Three Bridges via Horsham, and between Horsham and Dorking.
Passengers were advised to allow considerably more time for journeys via replacement bus, which may also involve joining up with other, diverted rail services.
Car-parks at Arundel and Crawley stations will be closed on the dates outlined above, so that they can be used to support the delivery of the work and the operation of bus replacement services.
In detail, here's what will be done:
- A section of rail, sleepers, ballast and drainage will be renewed at Horsham station including nine sets of switches and crossings
- Track improvement work at Pulborough, Warnham and Barnes Green (Barnes Green Level Crossing will be closed from Thursday 19 August to Sunday 22 August).
- In depth inspection and maintenance work will be carried out across 43 miles of closed track during the 9-day line closure
- Replacing track circuits (the part of the signalling system that detects trains) along the Arun Valley, and replacing signal heads between Horsham and Crawley.
- Deep cleaning, refurbishing, decorating and essential maintenance of all closed stations - Crawley, Ifield, Faygate, Littlehaven, Holmwood, Ockley, Horsham, Christs Hospital, Billingshurst, Pullborough, Amberley, Arundel
Network Rail said reliability along the line would be increased after the work.
Much of the Arun Valley line dates from the 1980s and needs to be replaced.
Management added that draining improvements would reduce the risk of flooding on the line.
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