 Before the 1930s, there were tide gates installed on this channel to only permit boats to pass when the level in the (at that time) semi-tidal Lee Navigation and tidal Old River were the same.After the 1930s flood works on the Bow Back Rivers, and construction of the Carpenter's Road and Marshgate Lane locks, these – and the Pond Lane Flood Gates were redundant as this section was controlled by the new locks – and the (then) tidal lock at Bow Locks.In 2000, Bow Locks were modified to keep the tide out; this reduced silting in this section of the canal – and made the water level completely controlled.