Later, Duane pursued independent practice. His structural design projects include public works such as the Seattle Water Operations Center, the Stevens Hospital expansion in Lynnwood, the Mount Vernon (WA) Waste Water Treatment Plant, and wind turbines. He designed several residences in the Pacific Northwest, including two of his own in Lake Stevens and on Whidbey Island. Duane retired in 2006.
In 2010, the American Society of Civil Engineers recognized Duane McMahan as a Fellow of ASCE.
Posted April 2012, updated November 2012, August 2016
SEAW Seattle President 1989, Life Member 2000
Duane Craig McMahan (1934-2016), a native of Great Falls, Montana, received the BSCE and MSCE (1964) from the University of Washington.
At the time of his SEAW membership application in 1967, he had worked in various capacities as a structural engineer for Marshall, Barr & Associates, John Graham & Co., and Worthington, Skilling, Helle & Jackson. He then went on to work with R. W. Beck & Assoc., Victor O. Gray & Assoc., and KPFF [then Kelly, Pittelko, Fritz & Forssen], before establishing his private practice in 1978 as McMahan Consulting Engineer. He and Ed Baker formed McMahan & Baker as a partnership in 1983, and in 1985 Dean Froerer joined the firm then known as McMahan, Baker & Froerer/MBF.