On airport layout plans and utility maps, a "dotted" or "dashed" line typically represents underground utilities or proposed/future infrastructure. Specifically, in the context of electrical or fueling systems, a dashed line often indicates a subterranean conduit or a pipe that is not visible from the surface. In broader aviation mapping (like on an Airport Diagram), a dotted line might signify a low-visibility taxi route or a boundary for a "non-movement area," which is a part of the airport where pilots can taxi without specific clearance from Air Traffic Control (ATC). If the line is specifically a "short-dashed" line along a taxiway, it often marks the "ILS Hold Short" point—a critical boundary that pilots must not cross when an aircraft is landing in poor weather, to avoid interfering with the sensitive radio signals of the Instrument Landing System. The exact meaning can vary slightly depending on the specific "legend" of the map (FAA vs. ICAO), but it almost always signifies something that is either hidden beneath the pavement or a "soft" boundary rather than a solid physical barrier.