Changes

When originally built in 1876-77 as part of the [[Kidderminster Loop Line]], the tunnel was lined with red brick and was 19ft wide. Unfortunately the sandstone through which the tunnel passes deteriorates on contact with air, and within 10 years part of the arch had given way under the weight of sand. Over the next 20 years, further small sections of the tunnel were relined, but in 1908 the decision was taken for the tunnel to be fully relined with two rings of blue bricks set in cement. The work began on 12 June 1910 and was carried out between August and completed on 20 October 1910. <ref>[[Bibliography#Books|Marshall (1989)]] p. 92.</ref> For safety, an occupation instrument was installed at the Bewdley end of the tunnel, linked to the [[Kidderminster Junction signal box | Kidderminster Junction]] and [[Bewdley South signal box | Bewdley South]] signal boxes. After the last train of the day had cleared the section, withdrawal of the occupation key would prevent the release of the electric train staff at either end until work in the tunnel had been completed overnight and the occupation key replaced.<ref>SVR News 109, "Relaying of Bewdley Tunnel, 1910", John Marshall</ref>