The Powell Bill Unit of the NCDOT annually distributes a fixed appropriation from the State Highway Fund to qualified North Carolina municipalities to maintain municipal streets within their corporate limits. Presently the funds are distributed by a formula allocating 75% of the money based on municipality population and 25% based on municipality street mileage. This formula does not take into account municipalities that are affected by seasonal population shifts or by the large military presence in North Carolina. However, such shifts do exist. The objectives of thsi research are to estimate seasonal population shifts of NC municipalities and to develop recommendations for Powell Bill funding allocation to reflect the impact. The research defined seasonal population as the number of visitors to a municipality who stay from one day up to six months in a given year. The research team assessed the funding distribution formulas of 50 State Departments of Transportation (DOTs) in the united States and foudn that 11 DOTs distribute funds based only on population, 6 DOTs based only on mileage, and 18 based on both reliable and feasible sources to account for seasonal population are 2010 U.S. Census data, 5-years American Community Survey, Seasonal Tourism Volumes, and July 1 Population Estimates by North Carolina Office of State Budget andManagement. A seasonal population estimation formula utilizing all the abouve 4 sources was selected to provide the most reliable and current estimates. In addition, 3 fudnign allocation strategies based on cap, group, and need approaches were develooped to better address the impact of seasonal population. An Excel based tool was provided to assist NCDOT engineers and adminstrators to modify the parameters of the proposed allocation strategies so that administration decisions can be made accordingly. Thsi research also found that military vehicles do not exert an exacerbate damage to local streets based on literature review and interviews with multiple military personnel.
