On 17/05/07, Adrian Stott <[EMAIL PROTECTED]> wrote: > > > To deal with this, instead of altering the new gates (which was > claimed to be much too difficult, although it never appeared so to me) > BW first started insisting that all locks be left empty with the > bottom gates open (that's a *great* way to save water on a notoriously > water-short canal, eh?), then started building bywashes all along the > canal. > > Too bad.
But is it? I would conjecture that the reason by-weirs weren't built on canals was simply a matter of cost. Building overflows wells, channels and culverts would have been a far pricier business than simply ensuring lock gates were set at different levels. In other words, you could argue that as a more sophisticated solution to a problem (and one that ensures safer and easier boating), replacing by-weirs is simply doing what the original engineers would have done if they'd been given free rein. Certainly I wouldn't have any concerns about the loss of heritage if BW built new by-weirs on the Rochdale 9, any more than I did when they put baffles over the gates of some locks on the Calder and Hebble to make them safer. Steve [Non-text portions of this message have been removed]
