Bristol Water explain the reason why rainfall does not mean restrictions can be lifted.
One Worcestershire fisherman said water levels were probably the lowest he had seen.
The Missing Mile project will create a navigable route from the River Severn to the River Thames.
The canal cannot go along its old route, so volunteers are digging a new channel.
If the order is granted, it would reduce the minimum amount of water required by law in the River Severn.
Flood prevention work is taking place, in a bid to use land as a sponge for the River Severn and River Tern.
The battery-powered Surfbee carries out autonomous "missions" accessing hard-to-reach locations.
The region has entered into official drought status after a prolonged hot, dry spell.
The number is the equivalent of approximately 80 Olympic-sized swimming pools.
