Tunnel 22 on Christchurch to Picton line disappears

A news report on Tunnel 22 on the Christchurch to Picton railway line which has disappeared as machinery straightens the line. Frank Perry reports on the improvements to the line, which is probably the most criticised in t he country, as it is a lifeline to manufacturers but prone to slips. The Kaikoura coastline could still bring troubles as the land is often unstable when there is heavy rain. Railways engineer Murray Kennedy is interviewed about past closures and the improvements.