A PROBABLE explanation of the tunnels found behind Brook Street (Times, June 9) is that they were part of the mid-19th century improvements to the town?s water supply. The end chamber in the rock may have been a local reservoir, like that below the Pimple on Whitchurch Down (see Times, July 27, 2000). Old maps which can be seen in the museum at Court Gate show a leat coming from the Bannawell area along the hillside, passing under Kilworthy Lane, and above Exeter Street. In a map of 1842 the leat ended far up Exeter Street, probably at a conduit head; in 1867 it appears to have supplied piped water to a terrace of six houses here. Further back on its course, the 1867 map shows that east of Kilworthy Lane the leat was 200 feet (61.5m) distant from the wall below Exeter Street where a tunnel entrance has been exposed and whence water could have been piped to the houses in Brook Street. The measurement is near enough to Mrs Thompson?s estimate of the length of the excavation to support the suggestion that a reservoir was supplied from the leat. In 1885 the leat was still running, but appears to have been piped after passing Kilworthy Lane. It was to be obliterated by the building of the railway embankment and Drake Road in 1890. In 1865 a large reservoir was made further up Kilworthy Lane. There must have been records of the position of the water mains but they are not apparent on the Ordnance Survey maps. The minutes of the nuisances removal committee (1855-1872) were lent to the Record Office in Exeter for safe-keeping, and should be available on microfilm; there may also be newspaper accounts of the committee?s activities. Dr Mary Freeman Parkwood Road Tavistock
