America saw off the challenge of Finnish favourite Heikki Sorsa to take a 1-2-3 of medals and add to the gold won by Kelly Clark in the women's event.
Powers, 22, took gold with a best score of 46.1 achieved on the first of his two runs.
That was enough to edge out team-mate Danny Kass to silver.
Nineteen-year-old Kass also got his best of 42.5 at his first attempt.
High-lights of his display came in the shape of a corkscrew turn and his famed "Kasserole spin" - two upside-down twists while grabbing the board.
Jarret Thomas, saved his best until last as he helped the US complete their first Winter Games clean sweep since 1956 by storming in for the bronze.
Lying ninth after his first round, Thomas, also known as JJ, had the crowd whooping their appreciation with his second run played out to the strains of Madonna's Material Girl.
His score of 42.1 pushed Italian Giancomo Kratter out to fourth with Japan's Takaharu Nakai in fifth.
Sorsa, sporting a distinctive Mohican hairstyle, eventually finished a disappointing seventh.
After clinching his gold, Powers also praised the superpipe used at Park City for creating a thrilling spectacle for the 30,000 spectators.
With its 4.9 metre-high walls the pipe is one of the highest on the international circuit.
"The superpipe has changed the riding. People go for more amplitude now and are going for it a little more," he said.