Well just PM me and ill let you have his contact details or ill even introduce you. He’s a dam good guys whose always supportive of people who are interested.
One book I will say is absolutely essential if studying the Severn is Brian Waters Severn Stream. Its out of print now but there are lots of copy’s available second hand.
Brian Waters was born in Tewksbury, Gloucestershire in 1907. He was an author, editor and poet, he wrote and published several books; most notably Severn Tide in 1947 and Severn Stream in 1949; both books telling anecdotal stories about his travels along the river Severn. Waters’ books are in fact significant accounts of our past and give us an insight into the lives of ordinary people; people who believe that their history is not important enough to become history.
More about him here
https://riversevern.wordpress.com/about/