Derek was the main person responsible for identifying the archaeological importance of the Severn Estuary.
Professionally a skilled steelworks technician at Llanwern, much of his spare time was spent in the estuary and he was warden of Magor Marsh Nature Reserve. His discoveries reflect a lifetime's familiarity with the estuary and its traditional ways of life. The sites he found include Mesolithic human footprints at Uskmouth and Magor, the Bronze age sites at Caldicot and Redwick, Mesolithic, Bronze Age and Iron Age sites at Goldcliff, and the Magor Pill medieval boat. He discovered so many sites that in 1995-6 the Board of Celtic Studies of the University of Wales set up a project to document his discoveries.
Derek's remarkable quality was that he most generously encouraged and worked with others to investigate the sites he discovered. The Severn Estuary Levels Research Committee was founded in response to his discoveries. In recognition of his achievements he was awarded an honorary degree of the University of Wales on 18th April 1998 and in 2003 the interpretation centre of the Magor Marsh Nature reserve was named the Derek Upton Centre in his honour.
A fuller appreciation of Derek Upton's life and work is in Archaeology in the Severn Estuary vol 16 (2005), pages 1-6