Mearley Brook moves west from Worston Moor to Clitheroe, where it is joined by Worston Brook (coming from Worston and itself fed by Rad Brook, which drains Downham Moor) and turns south through the town of Clitheroe, in which it is joined by Shaw Brook (draining the south side of High Moor).
Mearley Brook continues, feeding a reservoir at Primrose before joining Pendleton Brook south of Clitheroe.
Howcroft Brook flows south through Ashendean Clough beneath Pendle Moor and skirts round the south of Mearley Moor before moving westwards, meeting Pendleton Brook just before the latter reaches Higher Standen.
