A planning and consulting firm with expertise in local governments has suggested ways the town can collect fees, known as "impact fees," to help pay for certain costs associated with growth. Impact fees are "one-time payments for growth-related infrastructure, usually collected when building permits are issued," Michael Gillooly of TischlerBice out of Bethesda, Md, told the Town Council at its Jan. 13 meeting. According to DeCarlo Brown, when he was hired as South Berwick's town planner and economic development director, he was told that learning about and setting up ways to collect impact fees was a high priority.  In reviewing the town's land use ordinances, Brown found that the town is required to ask for impact fees for subdivisions, but "there wasn't any type of equation to ask for (them)," he said. Impact fees must be spelled out and related to costs resulting directly from a project and can be used only for those associated costs, according to Gillooly. For instance, if a town doubles the size of a fire station due to population growth, impact fees collected can be used only for the expansion of the station beyond its original size. The fees cannot be used for the town's existing costs, operating expenses or maintenance, but only for growth-related capital expenditures, he said. Furthermore, the fees must be expended in a timely manner and cannot be saved or "sat on." Impact fees can be calculated in three ways: to pay for past expenses that allowed for expanded services; to pay for existing infrastructure in anticipation …