November 24th – At some point between last week and this, Chasewater’s level increased and it overtopped the spillway weir, but now is sits a couple of inches below this, yet the canal valve remains closed off. How could it be so?
I remembered there is a small valve-controlled weir bypass sluice in the back of the 9-Foot embankment, and for the first time ever, it was open. I’m not altogether clear why.
Releasing water into the full canal would mean loading the Ford Brook/Tame waterway through Walsall and Birmingham via the overflow system, so releasing to the spillway would mean the water goes via the crane brook to meet the Tame near Tamworth, which would be better. I suppose using the sluice allows the dropping of the level of the main reservoir in a much more controlled fashion and creates buffer space if necessary.
It’s very unusual and I don’t think I’ve seen this approach in the seven years since Chasewater was refilled.