David Walter Fonken

David Walter Fonken passed away peacefully in his son Paul’s home in Estes on June 20, 2026, at the age of 94. He was born in Denver, Colorado on October 9, 1931 to Rev. Adelbert Anton Fonken and Mary Lois (Ward) Fonken. They initially lived in Hawk Springs, Wyoming, where his younger brother, Hillmer (Rick) was born. They moved to Fort Collins after Dave completed elementary school. He graduated from Fort Collins High School and Colorado State University (CSU). The Colorado Big Thompson project inspired him to pursue a career in civil engineering with a focus on hydrology, receiving bachelor’s and master’s degrees from CSU. On June 14, 1953, he married Shirley Marie Fonken in her hometown of Mitchell, Nebraska, after they both completed their undergraduate degrees at CSU. He served in the army from 1953 to 1955, surveying along the Koyukuk and Noatak rivers in the far north of Alaska during the summers and in California during the winters.

After completing his military service, Dave worked for Douglas Aircraft and the Bureau of Reclamation in Denver, where they had their first son, Royce. In 1958, they moved to Tucson, where their daughter, Gael, was born. Their youngest son, Paul, was born while they lived in Pakistan, where Dave was working on irrigation projects with Harza Engineering in 1961-1964.

Dave’s skills in computer modelling of large-scale irrigation projects took them to many locations over the years: Chicago, Tucson (where he earned a doctorate degree from the University of Arizona), Scottsbluff, Pakistan, Bangladesh, Egypt, and Tempe. He recalled carrying boxes of computer cards to the super-computer in Chicago’s Sears Tower to model Pakistan’s irrigation systems. He kept up with the evolution of information technology throughout his life. In his later years at Good Samaritan Village in Estes, he enjoyed armchair adventures via Google Earth and even virtually experienced trips down the alpine slide, which he could view from his window.

After all their wonderings, Dave and Shirley migrated back to their roots in northern Colorado. For many years, they spent their summers in Estes, where Paul and his wife, Erin, have been based since 1990. During Dave’s childhood, his family frequently visited Estes Park, Grand Lake and Fraser, since his father had contacts in the region after serving as the first pastor at the church in Fraser starting in 1911. Dave and Shirley loved hiking in Rocky Mountain National Park (RMNP) and spending time with family. Even at the end of his life, Dave could recite from memory the names of the peaks he could see from his “million-dollar view” at Good Sam’s. In 2009 Dave and Shirley moved to Estes full-time, enjoying the high school years of Paul and Erin’s children: Isaac, Elizabeth and Matthew. They stayed in Estes for the remainder of their lives, initially in a condo, then at Good Samaritan Village since 2018.

Shirley and David both enjoyed intellectual pursuits, even in their later years. He posted a chart about quantum physics alongside his RMNP quad map in his bedroom and loved to star-gaze at night, using his computer to name the stars. He also enjoyed photography and music and was very active with bands and choirs during his earlier years. Throughout his life he was able to recite from memory an amazing number of poems, lyrics and jingles. He also maintained some of his college relationships for his lifetime. He appreciated visits from family and interactions with the staff at Good Sam’s.

He is survived by his three children (and their spouses), seven grandchildren, four great-grandchildren, his brother and his wife, Elaine, in Fort Collins. Dave is preceded in death by his wife Shirley Marie (Gompert) Fonken who passed away on September 8, 2022 after 69 years of marriage.

A private family service will take place later. To leave messages for the family to read please visit www.allnuttestespark.com