More than 65 years later, David Barlas still weeps when he talks about Hiroshima and burned faces hidden under handkerchiefs.

Barlas was a master sergeant in the U.S. Army when he arrived at the demolished Japanese city, barely two months after the United States dropped the first atomic bomb there in August 1945.

“There were just three buildings left standing — city hall, the phone company and the police station — and that’s just because they were made of concrete,” Barlas said Thursday from The Watermark at East Hill in Southbury, where he lives with his wife of nearly 70 years, Ruth.

“The other buildings, I remember, were completely destroyed except for their safes, so you could tell where the stores were before the bomb.”

On Veterans Day — and plenty of other days, for that matter — Barlas stops and thinks about those who served during World War II. Many of them never made it back to Brooklyn and Queens, N.Y., his old neighborhoods.

“Everyone else,” the 93-year-old Barlas said, “gave the best years of their lives.”

Somehow, in the charred and broken nightmare of Hiroshima, Barlas and his men with the 1067th Engineering Design Group were supposed to fix a water treatment plant.

Clean water was vital to Hiroshima’s recovery, of course. But the Americans weren’t exactly welcomed with open arms after killing and wounding an estimated 150,000 people there.

“When I spoke to the water plant supervisor, I asked him for drawings of the damaged area of the plant,” Barlas said. “He gave me one — and only one — drawing of the damaged area.

“After it was translated into English and my plan to fix the damaged area was translated into Japanese, we left for the day. The next day, the plant supervisor greeted us with an armful of drawings. We had earned his trust.”

On so many levels.

For Barlas, a former Danbury resident, reconstruction after World War II wasn’t just about rebuilding cities. It was about healing the wounds of war inflicted by the United States and its Allies.

A few months before the trip to Hiroshima, Barlas and the 1067th Design Group — a collection of engineers, surveyors, draftsmen and architects — were ordered to design a 1,200-foot bridge over the Rhine River in Cologne, Germany to replace the five bridges the Allies had blown up.

The German snipers on the other side of the river, however, weren’t so keen on the idea.

So Barlas launched a rowboat at 1 a.m. with three men inside — one to row, one to measure, and one to use a flashlight to signal back to shore — to get the numbers he needed.

“It was pure triangulation,” said Barlas, who worked during an era when a transit and a slide rule were a civil engineer’s best friends.

Barlas didn’t stick around long enough to see the bridge completed with its 39-inch “meter beams,” the only steel available. After he finished his drawings, Barlas was sent to the Philippines to design an airfield on his way to Hiroshima.

Orders are orders, after all.

After the war — Barlas was honorably discharged in January 1946 — he landed a job with an “engineering construction outfit” and moved around New York City before he and his wife settled on a basement apartment in Astoria, Queens.

“We paid $30 a month,” Barlas said with a grin and a nod.

A few years later, in a 1950 edition of The New York Times, Barlas finally saw a photograph of the completed Cologne bridge. The span was built next to a bombed-out bridge, whose broken skeleton stuck out of the river like two jagged dorsal fins.

Barlas earned his civil engineering degree from Brooklyn Poly in 1952 with a transcript that included 50 credits from a year of study at Georgia Tech while he was in the Army.

He had earned his first credits more than a decade earlier.

After studying design, calculus, surveying and other high-level courses at Brooklyn Technical High School, Barlas took night classes at Brooklyn Poly before he enlisted in the Army in April 1941.

“We were generally the children of immigrants,” Barlas said. “We worked hard because that’s what our parents did. They loved their country and so did we.”

David Barlas never forgot that message, even when the Army took him to the other side of the world to repair a water plant and the ugly wounds of war.