DISCO DAVE'S TUNNEL GUIDE
Flooding
The dreaded words, the one thing the tunneller can't defeat is the water table. It can vary tremendously on just a small site. At Birmingham the tunnellers constructing the Shovel and Bucket tunnel hit the water table at 9 feet. In tunnel 69 just 50feet away the water table was 15 to 20 feet. At the Sir Cliff Richard the protesters excavated a considerable amount of soil and dug a further 40 feet of tunnel prior to the heavens opening again and awakening the tunnellers to the fact that they had inadvertently tunnelled at least 6 feet beneath the water table. With a dug tunnel where solid clay or soil once was , water is only too keen to take advantage of cleared spaces. A flood doesn't stop when it reaches the pre tunnel water table, it just continues flowing along the narrow passages of your hard labour for seemingly as long as it sees fit. So making the danger of flooding the entire tunnel a very real possibly. Two tunnels at Faslane peace camp were abandoned due to flooding before the campers opted to dig an open cast tunnel. The Sir Cliff Richard tunnel at Manchester took a week to be evicted. In hindsight it could have taken a great deal longer if the protesters could have expended their energy on tunnel construction rather than removing gallons of water on at least five separate occasions. One memorable day the tunnellers spent 7 hours indulged in this necessary but exhausting task. They then emerged from the tunnel cold wet and hungry only to find, after a cup of tea, that the tunnel had flooded once again in the space of 15 minutes. Forlorn and despondent they all understandably headed for the pub to "drown " their sorrows. Despite this there was no serious tunnel collapse due to flooding (this was probably also due to to the sturdy composition of the Cheshire clay in that area). It was their added good fortune that during eviction a prolonged dry spell (unusual in Manchester) allowed the protesters to occupy a chamber that would have definitely had to be abandoned had it rained. Tunnellers in the Cakehole tunnel in the neighbouring Flywood camp faired considerably better. Having constructed their tunnel into a shallow hill they experienced no flooding problems and subsequently the eviction of the Cake Hole tunnel lasted 17 days.
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