After John Patrick O’Hagan treated his family to “Hamilton” a few years ago, he spent weeks thinking about the Broadway musical’s closing number, “Who Lives, Who Dies, Who Tells Your Story.”

The song explores how people’s legacies are built through the memories shared after their deaths. The message resonated with O’Hagan. So when he died last month, his daughters knew they would keep his spirit alive by telling stories about him.

Like when the lifelong Baltimorean conspired with his then-teenage daughter to write a prank letter to an unsuspecting family friend. Or how, under his leadership in the U.S. Army Corps of Engineers, the Port of Baltimore deepened its shipping channels to 50 feet. And how, in his last few years at a senior living facility, he joined theater and poetry clubs and founded a new one for the card game Hearts.

“He made it easy for everyone to be with him, because he was just a gentle, kind, joyful person,” said his oldest daughter, Mary Pat Lowe.

O’Hagan, who worked for nearly four decades in the Baltimore office of the Corps of Engineers and volunteered for local nonprofits in retirement, died Jan. 24 of complications from a fall. He was 88.

He was born July 9, 1937, the youngest of John Sr. and Mary Regina O’Hagan’s three children. His father was a cookie salesman; his mother, a homemaker. They raised their kids in Baltimore’s tight-knit Irish 10th Ward. O’Hagan spent his early years playing basketball and listening to cowboy stories on the radio, his daughters said.

He attended St. John the Evangelist Catholic School and served as an altar boy. At Baltimore Polytechnic Institute, he developed a love of engineering. But he was always more interested in the people and leadership behind the projects than the math and science.

He studied engineering at Johns Hopkins University and graduated in three years. O’Hagan was eager to start his real life — especially because he’d met his future wife, Eileen, at a square dance the summer before graduation.

After a couple years of dating, he bought a ring and proposed while she was cooking pork chops. She said yes because “he was funny, and some of the other boys she dated were just too serious,” Lowe recalled her mom saying.

Lowe was their first child, followed by a son, also named John, and another daughter, Kathy. John and Eileen often went to the movies on weekdays and shared late-night cups of tea before bed.

O’Hagan’s job kept him busy. He served as chief of the Corps’ operations division from 1971 until his retirement in 1997, overseeing dredging projects and the maintenance of dams and flood protection initiatives. He also supervised coastal construction work and ensured water resource projects followed federal guidelines.

Sandy Hanson, O’Hagan’s secretary for eight years in the 1970s and ’80s, described her former boss as a “work dad” who performed well under pressure.

O’Hagan mentored dozens of young people in the office and handed out praise readily. No one was ever scared to bring concerns to him, she said.

“He could work out solutions before the problem came to a head,” Hanson said.

Jeffrey McKee, who worked with O’Hagan for about two decades, said he was known as a diplomatic and selfless leader who built a staff diverse and capable enough to handle complex problems.

There was sometimes “controversy between what people wanted to construct in the waters of the United States versus what the Corps and the environmental agencies would allow,” McKee said. “He was very fair and even-handed in dealing with all sides.”

O’Hagan always made it home for dinner with his wife and kids. He brought his daughters to the local pool, attended their field hockey games and cheered for his son’s magic shows. Once, when his daughter Kathy was in middle school, she grew emotional over a tough algebra problem — so her dad showed her his old report card with a failing math grade.

“He had good humility,” Kathy O’Hagan Adams said. “He provided perspective and took the negatives and reframed them again.”

He loved talking about politics and history at dinner, especially if the topic was former President Franklin D. Roosevelt. He encouraged his children to share their opinions, his daughters said, and never gave unsolicited advice.

His four granddaughters called him “JP.” He played paper dolls with Mary Pat’s children and a made-up history game with Kathy’s kids.

In retirement, he tutored students at Mother Seton and St. Ignatius Loyola academies. He joined the Ignatian Volunteer Corps in 2000 and helped Baltimoreans struggling with their mortgage payments at St. Ambrose Housing Aid Center.

“People talk about lifetime learners,” said Kevin O’Reilly, a St. Ambrose volunteer. “He was always like that, asking lots of questions and trying to figure things out.”

When his wife got sick, O’Hagan was her primary caretaker and helped fulfill her wish of dying at home in 2012. O’Hagan struggled with his new normal, but he didn’t want to burden his children. He joined a bereavement group and a few years later moved to Mercy Ridge Senior Community, where the self-proclaimed “conversationalist” found new friends and hobbies. He once tried to organize a lunch with all of the men named John who lived there.

Even as his physical health deteriorated, he was “sharp as a tack” and maintained his sense of humor, O’Hagan Adams said. In 2012, he marched with his family in a St. Patrick’s Day parade for “apostrophe awareness,” as the punctuation mark was often left off his last name on his driver’s licenses.

He still traveled in old age, taking his family to see the FIFA Women’s World Cup in Montreal in 2015 and in Paris four years later. They toured an aqueduct in the south of France, and the family joked that O’Hagan was “82 and in a canoe.”

He lived a life vast enough that family and friends aren’t worried about running out of anecdotes, his daughters said. So they’ll keep sharing them — to keep his memory alive, to tell his story.

The Banner publishes news stories about people who have recently died in Maryland. If your loved one has passed and you would like to inquire about an obituary, please contact obituary@thebanner.com. If you are interested in placing a paid death notice, please contact groupsales@thebanner.com or visit this website.