They carry out essential maintenance between the first week in November and the second week in March. If they drained them willynilly they would leak like crazy when refilled. Who is going to pay for the subsequent repairs. It costs 2-3 million to repair a breach. How are you going to get the waterfront homes along the Canal to agree to them being drained. They look an eyesore when drained and would become dumping grounds for everyone’s rubbish. They also support a lot of wildlife fish etc. Manchester is a Cental hub for the meeting of the Bridgewater, the Rochdale and the Huddersfield canals and is part of The Cheshire Ring. The Manchester canal system waters feed The Bridgewater a private canal with over 4000 licensed boats. This canal is lock less as far as Preston Brook in one direction and Wigan in the other, after it splits at Trafford Park,just after The Swamp and is used 365 days a year. Without the feeds from the other canals. the water levels on The Bridgewater would drop and it would not be usable. Finally the canals are owned and maintained by The Canal and River Trust. Their Charter demands they keep the system open and fully maintained. They answer to The Enviroment Agency, a Government Department, not The Council,who have no control. So draining them for 4 months every year is not a practical solution.