Since 1974, he has taught maritime history periodically at The Evergreen State College and South Puget Sound Community College. Eldridge is co-author of The Wilkes Expedition, Puget Sound and the Oregon Country, Washington State Capital Museum, 1987, which Nathaniel Philbrick, in Sea of Glory, called an excellent discussion. Eldridge chaired the maritime committee of the Washington State Centennial Commission. He is a graduate in history of the University of Washington, and an alumnus of Harvard University’s Institute for Educational Management. He holds two certificates from the National Judicial College, in administrative law and dispute resolution.
Eldridge holds the National Association of Counties Distinguished Service Award and served for five years on its board of directors. He coached five gold-medal winning boats in the National Women’s Rowing Association championships during the 1960s. He is still active in rowing and tennis.
The Chesapeake Command Broadsides Press, November, 2005, was his first novel, and Gray Raiders, Green Seascontinues the Dunbrody - St. John series.