That stretch is a few miles away from me.
The site is designated a Local Nature Reserve by Natural England, includes a Scheduled Ancient Monument (a 300 year old Walnut tree) and a Community Asset managed by Dorset Council. No parking because there is no car access!
The fishing rights were sold at auction by a local agent in May 2018 for £10,000.
It's not exactly private fishing! Plenty of access to the opposite bank which is managed by a fairly local angling club who also make it available to other clubs via exchange books.
Good luck if you enter the bidding!
mg: