The National Spatial Reference System (NSRS) is a set of permanent monuments that act as the foundation for many activities requiring accurate spatial information. For example, when construction workers are working near a building, they need to know where the building lies in relation to power lines. Without the NSRS, the location of the buildings and the power line are unclear. View the imags below to see the difference the NSRS can make. By comparing the coordinates for the location of the building and the power lines, the construction team will have a clear picture of where things lie and can avoid potentially dangerous situations. Animated version.