John Patrick McGuire, born August 3, 1937, in the Bronx, NY, passed away peacefully in Enfield, CT, on November 24, 2025. He was predeceased by his parents, Patrick and Anne McGuire, and his beloved sister, Jeanne.

A proud graduate of MIT, John devoted his career to environmental engineering, a field he embraced with both curiosity and purpose. He founded and operated his own environmental water-testing laboratory in Tarrytown, NY, and took particular pride in his two successful businesses, Consolidated Technologies and Esarco. His work reflected his lifelong commitment to learning and using science to improve the world around him.

On March 15, 1992, John married the love of his life, Maureen McNally Lockwood McGuire, and with that union, he joyfully welcomed a family he cherished deeply. Nothing delighted him more than time spent with his grandchildren: Joseph (Melinda) Dempsey of Butler, TN; Kathleen Battle of Stuart, FL; Julien (Kenzie) Levesque of Medfield, MA; Haley Levesque of Danbury, CT; Nick (Kaycie) Villeneuve of Weare, NH; Nolan (Kate) Villeneuve of Burlington, VT; Margaret Marion of Enfield, NH; and Matthew Marion of Portsmouth, RI. Their accomplishments, visits, and stories were among his greatest joys.

John was a man whose curiosity shaped every chapter of his life, from the scientific questions that fueled his career to the conversations that filled his home. He asked thoughtful questions, pursued new ideas with enthusiasm, and encouraged others to do the same. His love of learning, his appreciation for problem-solving, and his delight in discovering how things worked remained constant throughout his years.

Services will be private.

n lieu of flowers, donations may be made to a charity of one’s choice.