The spill weir and side pond are separate structures on opposite sides of the lock. The side pond was a water saving feature. When the lock was emptied, some of the water was fed into the side pond. When the lock was later re-filled, this water was then used to partly re-fill the lock.
The side pond has not been restored, and it is unlikely that this would be used again on the restored canal.
The spill weir, which controls the maximum water level in the pound above the lock, was restored by the Cotswold Canals Trust in 1997.
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