 The canal has suffered several major breaches throughout its history . As early as 1799 a flood carried away large sections of the lower banks , and on 15 October 1853 two boats were swept through a 93 @-@ yard ( 85 m ) breach near the bottom of Nob End Locks ( no injuries were reported ) . Three breaches were reported from 1878 – 1879 , in Little Lever and Darcy Lever , the latter near Burnden Chemical Works . Subsidence , caused by mining activity , prompted a breach near Agecroft in 1881 . As a result of such incidents , from 1881 to 1888 engineer Edwin Muir was employed to reduce the subsidence caused by mining activity . Similar work was undertaken throughout the 1920s . Maps from the 1880s show that by then , to safeguard against further subsidence , the canal company had purchased areas of coal beneath the canal . In 1884 the canal 's owners , the Lancashire and Yorkshire Railway , successfully sued colliery owners Knowles & Sons for losses incurred from damage caused by subsidence . Following this judgement , the railway company settled out of court with other colliery owners . Constant repairs were made , particularly through Pendleton , where the embankment was periodically raised . Some bridges were lifted far above their original supports , while others sank as low as 8 feet ( 2 m ) above head height . 
