The River Tib is a very minor watercourse passing through the centre of Manchester. It is entirely culverted.
Early industrial Manchester would have attempted to use and abuse every source of water available. The River Tib had little to offer either for water supply or waste disposal, but it had a powerful influence in defining ancient legal boundaries, which imposed considerable constraints on the shape and extent of new properties during the dramatic development of central Manchester. As a result of this and other legal boundaries we still find evidence of buildings having curiously-shaped floor plans, in a city whose hard-nosed businessmen had no time for frivolity and where right-angles ruled, and no space was wasted.
The Tib's source was 'Cowper Pit', Miles Platting, subsequently covered by the L&YR works. (There was another stream passing nearby, whose source was Keene's Well, near the Newton Heath Brewery, Monsall Lane, which went under the L&YR's water tank. It passed under the Rochdale Canal at Royle's Bridge, joining Shooter's Brook at Gagg's Field near Butler Street).
The River Tib joins the River Medlock at Gaythorn.
Going back in time, Green's map of 1787-1794 shows that before the Rochdale Canal was built, the River Tib encountered a dam at Gaythorn, where the water was impounded to serve a mill on 'Messrs. Cheethams' land. To the east of the pond were two further reservoirs and an industrial building. The river then rejoined its old course for a short distance before joining the River Medlock.
This 1823 drawing shows that the place where the Tib joined the Medlock was already blighted by industry.
The 1849 O.S. map shows that the genrally culverted River Tib briefly saw daylight for a distance of 50 yds after passing Gaythorn Tannery. Otherwise, the area had seen massive changes which make it difficult to identify what had survived from the time of Green's map. There was still a reservoir, and possibly part of its adjacent building (identified as the Gaythorn Dye Works on the 1849 map, and Goodier's Dye Works on Adshead's 1851 map). The reservoir was probably now fed by the Rochdale Canal, which was immediately to the north. Immediately to the south was the viaduct of the MSJ&R. South of the viaduct and bounded by Albion Street and by the River Medlock was a plot of land containing dense housing and some highly undesirable neighbours in the form of Gaythorn Chemical Works (Coppock's), Bone and Size Works, Finch Street Size Works (belonging to Mary Bakewell), Gaythorn Tannery, Hood's Dye Works and, immediately west of the Tib, Medlock Bridge Mill and Gaythorn Smallware Manufactory. The 1894 O.S. map shows that this 'mixed industrial and domestic development' had been improved by the construction of Gaythorn Gas Works, which overlayed everything, Rivers Medlock and Tib included. At the north western corner of this area, at the end of the larger group of houses, was a pub named the Gaythorn Vaults (1849 map) and Gaythorn Tavern (1851 map), and survived as The Gaythorn until recently.
Sources of Information
- Manchester Times - Saturday 20 November 1880
-  Martin Zero YouTube video - 'The secret trap door under the canal'