In general, the "benefit" must result directly, uniquely and specifically from the public project. For example, when water and sewer lines are installed by government units, nearby land often increases in value. Both the presence of safe drinking water and of sewer lines means that expensive wells and septic systems do not have to be installed by affected property owners. It also means the potential for contamination of ground water and surface areas from improperly treated sewage will be eliminated. Land that might have been “unbuildable” before may become "buildable" once government provided water and sewer services become available. Providing water and sewer service are situations which may adapt formerly unusable land for residential or commercial use. A storm sewer or a dam or dike may mitigate flooding and therefore the sewer, dike or dam relieves a burden, flooding.