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The New Hotwell Quarry 2 Resurgence St. Andrew's Well U5 Black Rock Quarry Passage U4 Main Wall Grotto Cobweb Cave Severn Valley Dig Cave Shatter Hole Small Cave U8 Mercavity Cave Percavity Cave Tennis Courts Spring Pool Cave Mouse Hole St John's Hole River Bend House Cave Tube Cave
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Black Rock, Avon Gorge.
| NGR: | ST 56186 74415 |
| WGS84: | 51.46700, -2.63213 |
| Length: | 12000 m |
| Depth: | 90 m |
| Altitude: | 13 m |
| Tags: | Well |
| Registry: | mcr-b |
This is the outfall for a huge tunnel complex built to relieve flooding to large parts of Bristol. Known affectionately as the Motherload, the main tunnel is 8km long and 5m in diameter and begins at an intake on the River Frome.
Alternative Names: None recorded.
Notes: SU1 p.48
Links and Resources:
Search for this site in the MCRA Bibliography.
This entry was last updated: 2026-01-04 10:37:38
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