The River Darwen is a river running through the towns of Darwen and Blackburn in Lancashire which eventually joins the River Ribble at Walton le Dale. Here the river runs to the south of Preston on its way to the Ribble Estuary on the west coast of northern England.
Originating at Jack's Key Clough where Grain Brook and Grainings Brook meet, the two streams from Bull Hill and Cranberry Moss respectively, the river flows through the town of Darwen, continuing into the suburbs of Blackburn past Ewood Park. The river passes below the Leeds and Liverpool Canal at Ewood Aqueduct and is culverted again at Waterfall and near Griffin Park. It is joined by the River Blakewater near Witton Country Park in Blackburn and leaves the mostly urban landscapes of the towns behind, flowing through parklands and valleys. A further tributary, the River Roddlesworth, joins the Darwen at the bottom of Moulden Brow on the boundary between Blackburn with Darwen and Chorley Borough Council (the name Moulden Brow being associated with Moulden Water, an alternative name for this stretch of the river). From there, the Darwen flows past Hoghton Tower through Hoghton Bottoms and Samlesbury Bottoms, finally combining with the River Ribble at Walton-le-Dale.
" While Darwent Streams with Blood of Scots imbru'd..."
The river was polluted with human and industrial effluent during the Industrial Revolution, and this contamination continued until the early 1970s. The river often changed colour dramatically as a result of paper and paint mills routinely using the river water to flush out dye and paint tanks. This process has now ceased, and as a result the river water is now relatively clear which has resulted in the return of trout and small fish. In 2012 a section of the river which had remained in a culvert for 100 years was uncovered at an area of Darwen known as Shorey Bank Throughout the course of the river many improvements have resulted in improved water quality.