River Mole on the future cleanliness of the Mole was had by the House of Lords involving a member of the South-East Strategic Committee, of the Thames Conservancy (succeeded by the Environment Agency) and four others. In this it was said "...I can see no future for [The Mole]. The Mole Valley has been polluted. The Mole where I used to tickle trout in my youth is a drain, and it will remain a drain." Rebuttals included that the Mole is a "charming Surrey steam" and "If Lord Lytton went to fish in the River Mole—and there are still angling clubs there—he
Sutton and Mole Valley lines the landowner, Thomas Grissell, meant that vertical ventillation shafts could not be constructed and the tunnel portals were given lavish architectural treatment. Betchworth Tunnel is south of Dorking. It is long with a maximum gradient of 1 in 80 (1.25 per cent). It runs through the upper greensand of the Deepdene Ridge to the east of the town. Construction difficulties delayed the opening south of Dorking. It collapsed on 27 July 1887, remaining closed for over six months. Sutton and Mole Valley lines The Sutton and Mole Valley lines were constructed between 1847 and 1868 by the London, Brighton and