David Merwin paddled for the Turkeyfoot Kayak Club out of Hudson, Ohio. He attended Philips Exeter prep school where he rowed crew for two years, captaining the team in his senior year. Merwin attended Cornell, class of 1958, where he was also on the crew team. Merwin won the junior K-1 title at Dominion Day in Toronto in 1956, also winning the President’s Cup race in Washington, DC that year. At the 1956 US Olympic Trials, Merwin won the K-1 1,000 and placed second in the K-1 10K. Merwin won the 1957 US title in K-1 1,000 and helped Turkeyfoot KC win the 1960 US title in K-4 1,000.