John J. Zimmerman, a Rowayton resident for over 50 years, died Tuesday, March 8, at 84 years of age. He was born and raised by his parents Joseph and Marie née Schmidt Zimmerman in New York City.  

John served two years in the 773rd Antiaircraft Artillery Battalion, New York National Guard, during the Korean War. With an engineering degree from New York University, John had a long and successful career at Columbia University’s Engineering Research Laboratories, Heat Transfer Research Facility that spanned 42 years. He was a hard worker and was passionate about his field. The Heat Transfer Research Facility tested nuclear reactor fuel rods and documented the water cooling heat transfer characteristics of nuclear fuel rod bundles. Their troubleshooting of the equipment was instrumental in establishing how power plants operate safely. Many U.S. nuclear reactors and power plants are run based on the measurements made in the facility. This was the only lab of its kind in the U.S. and has since closed.

Inspired by his father, John also was an entrepreneur and in his younger years started many businesses including water filters, paper dresses, and Alternate Sources of Energy, a company that used solar, wind and hydro energy help produce clean energy. His interests included sustainable living, alternative medicine and history.  At one point, John was part owner of Wappingers Falls hydroelectric plant that was not operational at the time. John spent weekends assessing what repairs were needed until the plant was sold.

John had a heart of gold and spent his life helping others; he would give the shirt off his back or an interesting newspaper article to assist a friend in need. In additional to being knowledgeable on many subjects, John enjoyed collecting things. If someone needed something mechanical, it was very likely that John had the part. If John didn’t have the item, he certainly knew where to find it.

In addition to his wife of 55 years, Moira née Simpson Zimmerman, John is survived his daughters, Eileen Duke (Richard) of Gypsum, Colo.; Jo-Anne Zimmerman of Wentworth, N.H.; and his son Ian Zimmerman (Sarah) of Wilton, Conn., and their children Emily and Christopher. John’s surviving extended family includes a brother-in-law, nieces and several great-nieces and nephews. He was preceded in death by his daughter, Cara Buhler (Franz) of Tucson, Ariz.

Please join us for a memorial to celebrate John’s life from 1 to 1:45 p.m. on Saturday, March 26, with military honors immediately following the memorial. The memorial and military honors will take place at the Hoyt Funeral Home, 199 Main Street, New Canaan, Conn.

For online condolences and directions, please visit hoytfuneralhome.com.