 Although the canal was originally designed to be a narrow canal with narrow locks for boats 7 feet ( 2 m ) wide , in 1794 an agreement was reached with the Leeds and Liverpool Canal company to create a link near Red Moss near Horwich , so broad locks were built to accommodate the 14 feet ( 4 m ) wide boats using that canal . This meant removing some of the narrow locks that had already been built . An extension to the original canal feeder was built at Weddell Brook in Bury , alongside the River Irwell . The route of the Leeds and Liverpool Canal was changed , however , and the planned link never materialised . The design changes to the canal were not completely without merit , since they allowed two narrowboats to use each lock simultaneously , saving passage time and water . 
