 20 miles ( 32 km ) long , the River Frome rises in the grounds of Dodington Park in the Cotswolds of South Gloucestershire , flows through Chipping Sodbury in a north westerly direction through Yate , and is then joined by the Nibley brook on the left at Nibley . The river turns south towards the next settlement of Frampton Cotterell , where it is met by the <unk> brook on the right bank . Continuing southwards between Yate and Winterbourne , the Frome crosses Winterbourne Down , to <unk> Bridge where the Folly brook tributary merges on the left bank . 
