The River Blakewater is a river running through Lancashire, giving its name to the town of Blackburn.
The Blakewater rises on the moors above Guide near Blackburn as Knuzden Brook and runs through the hamlet of that name, before taking the name Blakewater (meaning either "black water" or "clear water," the latter deriving from Old English blæc) near the village of Whitebirk.
From there, the river runs through the Blackburn areas of Little Harwood, Cob Wall and Brookhouse to Blackburn town centre.
The section of the Blakewater running through Blackburn town centre was culverted during the industrial revolution, and now runs underground. The culvert was extensively modified in the 1960s during the redevelopment of the town centre - it now runs underneath Ainsworth Street and between Blackburn Cathedral and Blackburn Bus Station. In recent years, the town has undergone a phase of regeneration with future proposals to open up parts of the culverted river so that the Blakewater will once again flow openly through areas of the town centre.
On the western side of the town centre the Blakewater continues under Whalley Banks and through the Redlam area.
The Blakewater joins the River Darwen outside Witton Country Park in Blackburn, which continues on to join the River Ribble at Walton-le-Dale.
In addition to the aforementioned Knuzden Brook, the waters of the Blakewater are swelled by Little Harwood Brook (coming from Sunny Bower), Audley Brook (from the region of Queen's Park to the confluence near Darwen Street) and Snig Brook (which rises near Lammack and runs through Corporation Park).
