Delta is the largest city in Millard County, Utah, United States. Delta is located at the north eastern end of Millard County along the Sevier River and is surrounded by farm land. The population was 3,436 at the 2010 census.
Delta was originally a railroad switch called Aiken. In 1905 Aiken was renamed Melville when Millard County began plans to set up irrigation and a dam. People purchased land for 50 cents an acre as long as they agreed to develop a 40-acre lot. The name was changed again because of the similarities between Melville and Millville, another town in Utah. The name was changed on May 12, 1908 to Burtner. The name was finally changed to Delta on May 11, 1911. The name is quite fitting as the area was a delta of the Sevier River.
During World War II, after the attack on Pearl Harbor, tens of thousands of Japanese-Americans were gathered up and placed in 10 incarceration camps with the intention of protecting military installations from espionage.