Rumworth Lodge Reservoir is a large shallow reservoir in Bolton, Greater Manchester, England. It is located to the west of Bolton's A58 (Beaumont Road) and to the South-East of Lostock railway station. The water from the reservoir is not used for drinking water but provides compensation water so that the Middlebrook, which downstream becomes the River Croal, never runs dry. It is a magnet for birds, particularly on spring and autumn passage when many rare species have been recorded. Fields between the wood and the lodge are also the site of rare autumn crocus.