In my early teens and up to 1965 or so I spent a great deal of time on the River Ryton, mainly in the Blyth area and down to where it joined the Idle. In those days it was a little gem and held good chub and roach, although they didn't reach any great size.
The biggest chub I ever caught from there would hardly make 4 lbs and I don't think I ever had a roach over 1 1/2 lbs.
But what made the Ryton so special for a short period amongst a few of it's enthusiasts were the dace. They went to well over the pound mark. I caught one of 1 lb 4oz on long trotted redworm ca 1959. Tag Barnes caught many over 12 oz but I don't ever recall him getting a pounder.
John Ledger also loved this little river but I think he missed the explosion of big dace that took place in the 1955 to 1962 period.
Today there is little I can tell you. The Ryton, has probably been "cormoranted and ottered out" if you ask me to say nothing of bore hole abstraction. It's flow looks only to be a fraction of what it was.
Maybe there are others who might be able to tell a better story.