Julius Walker Adams was born on October 18, 1812, in Boston, Massachusetts.

He was an American civil engineer and railroad engineer. Adams was the second cousin of President John Quincy Adams. In 1830, he entered the United States Military Academy, where he studied for two years, but resigned to start working as an engineer for his uncle George Washington Whistler. From 1832 to 1844, he acted as assistant engineer on the Providence and Stonington Railroad and the Paterson and Hudson River Railroad. In 1856, he switched from railroad engineering to designing. He supervised the first large-scale urban sewerage and drainage system in the United States for Brooklyn, New York (1857-1860) and became an engineer for New Haven's water works. During the Civil War, he became a colonel of engineers and of the 67th New York Volunteers while serving in the Army of the Potomac (1861-1863). Wounded in the 1862 Battle of Seven Pines in Virginia, he resigned and returned to Brooklyn, where he was a consulting engineer in New York City. From 1869 to 1878, he served as chief engineer of the Brooklyn Board of City Works, and from 1878 to 1889, a consulting engineer of the board of public works of New York City. He co-founded the American Society of Civil Engineers in 1852 and served as its president from 1874 to 1875. Adams was an editor of the Engineering News (1881-1882) and became a member of the American Academy for the Advancement of Science and of the New York Academy of Science.

In 1835, he married Elizabeth Denison (1812-1888). He died on December 13, 1899, in Brooklyn, New York.