The City of Delta is a Home Rule Municipality that is the county seat and the most populous city of Delta County, Colorado, United States. The population was 6,400 at the 2000 census. The United States Forest Service headquarters of the Grand Mesa, Gunnison, and Uncompahgre National Forests are located in Delta.
According to the United States Census Bureau, the city has a total area of 5.5 square miles (14.3 km²), of which, 5.3 square miles (13.8 km²) of it is land and 0.2 square miles (0.5 km²) of it (3.62%) is water.
There were 2,569 households out of which 31.5% had children under the age of 18 living with them, 52.1% were married couples living together, 12.3% had a female householder with no husband present, and 32.2% were non-families. 28.8% of all households were made up of individuals and 15.5% had someone living alone who was 65 years of age or older. The average household size was 2.45 and the average family size was 3.02.
In the city the population was spread out with 27.2% under the age of 18, 7.7% from 18 to 24, 24.1% from 25 to 44, 20.8% from 45 to 64, and 20.3% who were 65 years of age or older. The median age was 38 years. For every 100 females there were 89.2 males. For every 100 females age 18 and over, there were 85.5 males.
The median income for a household in the city was $27,415, and the median income for a family was $34,798. Males had a median income of $30,658 versus $20,383 for females. The per capita income for the city was $14,369. About 9.9% of families and 14.4% of the population were below the poverty line, including 22.0% of those under age 18 and 10.6% of those age 65 or over.