Ever see the CRT? (Canal and River Trust of England)

Locks are a what happens to allow the capture of water to hold it's level for that particular section of the canal and allow for the raising and lowering to the next piece of water. Without locks England's canals would be dry ditches.

In the case of the Suez there is no lack of water no need to hold or release and there is no need to change water levels this make the canal work. As a result the tide affects the Suez more so then most but if your ship stays within the plotted canal the water level changes don't affect the ship as much either.