contracts with the Clay County Fire-Rescue Department for fire and medical services. Post office A U.S. post office was established at Hibernia on June 19, 1849, but its name was changed on October 17, 1853, to Magnolia Mills, and on July 30, 1866, it was changed to Green Cove Springs. The Hibernia post office was reestablished on February 16, 1855, and remained open until May 15, 1931, when it was closed and the area assigned to Green Cove Springs. Geography Green Cove Springs is located on the eastern border of Clay County at (29.992716, –81.683786), along the St. Johns River. U.S. Route 17 passes through the center of town as Orange Avenue and leads north to downtown Jacksonville and south to Palatka. State Road 16 departs west from the center of the city and leads to Starke. SR 16 leaves eastbound from US 17 south of the city center and crosses the St. Johns River by the Shands Bridge, leading to St. Augustine to the east. By the late 2020s, the First Coast Expressway, a major toll bypass road connecting I-10 and I-95, is expected to pass to the west and south of Green Cove Springs. According to the United States Census Bureau, the city has a total area of , of which are land and , or 25.35%, are covered by water. Green Cove Springs is the Clay County seat. The Greater Green Cove Springs area consists of the unincorporated communities of Fleming Island, Black Creek, Pier Station, and Lake Asbury. Demographics As of the census of 2010, 6,908 people, 1,987 households, and 1,402 families were residing in the city. The population density was . The 2,199 housing units averaged 322.6 per square mile (124.5/km2). The racial makeup of the city was 71.55% White, 24.40% African American], 0.41% Native American, 0.54% Asian 1.38% from other races, and 1.73% from two or more races. Hispanics or Latinos of any race were 5.08% of the population. Of the 1,987 households, 28.9% had children under the age of 18 living with them, 50.2% were married couples living together, 16.2% had a female householder with no husband present, and 29.4% were not families. About 24.8% of all households were made up of individuals, and 12.3% had someone living alone who was 65 years of age or older. The average household size was 2.51, and the average family size was 2.96. In the city,