 About 13.7% of families and 21.5% of the population were below the poverty line, including 24.0% of those under age 18 and 11.6% of those age 65 or over.Williamsport operates on a "Strong Mayor" form of government, meaning the mayor is given almost total administrative authority and a clear, wide range of political independence with the power to appoint and dismiss department heads without council approval and little need for public input.The mayor is Derek Slaughter.