The Latest U.S. Census Bureau Figures Are In And Kingsport Outpaced Johnson City And Bristol Over The Past Ten Years. The Report Shows Kingsport Grew By Over 15% Compared To Bristol’s Growth Of 1.7% And Johnson City’s Increase Of 12.5%. The Model City Also Ranked As The 12th Largest Municipality In Tennessee. As For Counties, Washington County Grew The Most, Increasing In Population By 8.2%. The Combined Population Of Sullivan, Washington, Greene, Hawkins, Carter, Johnson And Unicoi Counties Is Over A Half-A-Million.