A canal breach is a rare and interesting occasion to see an old canal in cross section.
Many older canals tend to be 'saucer shaped', because boats weren't expected to moor except at special wharves. In the official BW photo of the breach, sent out over the weekend, this saucer profile is noticeable:
But I was especially interested in the silt and the clay puddling, and how deep it appears to be compared with the water depth. Almost the height of a man in places. Is most of this silt? Did it need dredging? And if so, could dredging actually cause further trouble?
And what about the embankment? I don't know geology or canal construction but I'd be interested to know where the local geology ends and the Georgian artifice begins (particularly at the point where the breach occurred).
The canal received its Act of Parliament in 1776 (according to assorted people I don't know or trust on Wikipedia), and it was built in a short three years, at a time when Parliament was perhaps otherwise engaged with events across the Atlantic. It's possible to wonder what shortcuts were taken in building the embankment in time and to budget. I mean, for an embankment to fail in a scant 230 years suggests the builders were a bit distracted, surely.
So in a sense this breach is a slice through history and a chance to see how they made the embankment. Aside from a view through time, the breach is also an opportunity to examine the site from above too.
The canal here winds around the fields because it's on a contour, not because it's manouvering between competing landowners. You can see the breach site from above on the Bing Maps aerial view here. I think Bing uses the same satellite photos as Google Maps, although Bing seems to have stitched them together more neatly.
Another interesting thought is that the canal runs around the edge of the valley housing the Leek Sewage Treatment Works. I wonder what effect the breach had on that. If it flooded the works, that would be a problem.
Granny Buttons was last at the breach site about 18 months ago, over Easter 2008. I went for a midnight stroll over Leek Tunnel top, and photographed the valley, looking back towards the site of the breach. The field right ahead of the camera is where it flooded.
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