Upon reading my feature package on repowering the Welland Canal, one reader asked me if the 24 million gallons of water flowing through a lock is captured to generate power each time a ship passes. It was a good question given that not to put it toward that use seems like a terrible waste of massive water movement.
I asked my hosts about this when I visisted the Welland Canal on Nov. 9 at lock 3, standing next to older weir along side the lock. At the time, water spilled over that weir, but no power was generated. It was drainage only. The Taintor valves that control the in- and outflow of that 24 millions gallons run free of power generation, probably because the 24 million gallons has to enter and exit in 7-10 minutes to quickly dispatch the vessels. Adding generators would presumably slow down the flow.
However, the canal’s U.S. and Canadian overseers signed an agreement last year to build three hydro plants that uses existing weirs to capture "run-of-the-river" water that spills over them. The weirs handle the overflow water that does not pass through the locks. Why didn’t I think of that — after 75 years of operation!? Each power station will produce 2 megawatts and in together promises to power 5,000 homes, so sayeth the canal’s overseers.