RAIL commuters in North Kent face an entire year of delays when two tunnels plagued by chalk collapses will close for 12 months for major repairs.

Strood and Higham Tunnels will close from January 17 2004, adding half an hour each way to journeys because of a shuttle bus service between Strood and Higham stations.

Network Rail says the upgrading will allow trains to return to their 70mph speeds as the limit is now 20mph.

The tunnels have had numerous chalkfalls since 1957 but the Strood tunnel has been particularly badly hit in recent years with major collapses in 1999 and 2000.

The Strood tunnel, built in 1847, runs through chalk land between Gravesend and Gillingham. It was the scene of a major landslide four years ago when four carriages of a train were derailed.