The Welland By-pass, completed in 1973, was a massive construction project on the Welland Canal in Ontario, Canada.
A new channel 13.4 km (8.3 mi) long was constructed, providing a shorter, more direct alignment between Port Robinson and Port Colborne and by-passing downtown Welland. The project helped improve navigation along the canal and alleviated problems the presence of a busy ship canal was causing in Welland.