Douglas Earl “Doug” Denninger, age 76, of Minong, WI, died on Sunday, August 31, 2025, at Essentia-St. Mary’s Medical Center in Duluth, MN.

Doug was born on May 23, 1949, in Hayward, WI, to Calvin and Gladys (Link) Denninger. He graduated from Northwood High School in 1967 and from the University of Wisconsin-Superior in 1971. On January 24, 1970, Douglas married the love of his life, Mary Ardelle Oestmann, sharing 55 years together. He taught at Northwood School 33 years, from1971 to 2004. He taught K-12 Art, aviation, and photography, served as a class advisor, and was a lead negotiator for support staff across local districts.

Doug served 48 years on the Frog Creek Town Board, many of those as Chairman, and 10 years on the Washburn County Board. He was instrumental on the committee that established the Transfer Station as we know it today. Doug also served 14 years on the Northwood School Board and proudly handed out diplomas to each of his grandchildren at their graduations. In 2007, he was inducted into the Northwood Wall of Fame.

Outside of public service, Doug was a farmer at heart establishing Denninger Farms in 1962. He was a Washburn County Sheriff’s Deputy, and worked at Link Recreational while attending school, and Link RV selling campers from 2004 to 2007. He earned his pilot’s license at age 16 and flew single and twin-engine planes including the Cessna 310, and later got a commercial license as well, and shared his passion for flight with students.

Doug loved spending time with family and friends, farming, hunting, riding UTVs, and boating on the Minong Flowage as the Frog Creek Minnow Captain. He had a gift for making people feel welcome and was always ready with a joke.

Doug is survived by his loving wife, Mary; children: Douglas (Tammie) Denninger and Dawn (Chad) Haakenson; grandchildren, Derek (Katie) Denninger, Amber Denninger, Taylor (Al) Goettl, and Gavyn (special friend, Kayla Boutwell) Haakenson; great-grandchildren, Carson Denninger (special friend, Zoey Wilson), Kloe Denninger (special friend, Will Holmstrom), and Lincoln Goettl; sister, Judith (Vernon) Rondeau; and brothers and sisters-in-law, Robert (Linda) Oestmann, Gary Oestmann, Jo (Steve) Hiller, Joy Serra, and Gene (Marge) Oestmann; and many nieces, nephews, and cousins.

He was preceded in death by his parents, Calvin and Gladys Denninger; and parents-in-law, Walter and Ardelle (Ehlers) Oestmann.

A celebration of life will be held on Saturday, September 6, 2025, from 11:00AM to 3:00PM at the Frog Creek Town Hall.

Last Update: Sep 04, 2025 9:05 am CDT