Rowley Bottom in 1806

The lock flight has finally opened and the Inclined Plane has been abandoned. The water for the locks is drawn from the Cam Brook and accumulates in the now isolated Lower Reach. From there it is flows through an underground adit towards the engine well from which it is pumped up 135 feet into the top reach.
As boats use the lock flight, the water makes its way down the flight to the lower level at Lock 22, from where it runs over a spill-weir back to the Cam Brook. At a later date, the Weigh-House would return the water to the Cam, using one lockfull per boat weighed.
The Lower Reach, by acting as a reservoir, ensured that the engine always had a good supply of water. It was also probably a useful settling pond for silt which had to be prevented, as much as possible, from entering the canal. A stop point near Lock 19 would allow the passage of boats for the purpose of removing silt when necessary.
The water flow in Rowley Bottom was complex