1. A method comprising: receiving, using one or more computing devices, a plurality of data points via one or more sensors, each data point representing a position and elevation of a surface; determining, using the one or more computing devices, a first set of data points based on one or more positions of the plurality of data points; determining, using the one or more computing devices, a plurality of portions of the surface wherein the positions of a plurality of the data points of the first set are located in each portion; identifying, for each portion of the surface and using the one or more computing devices, a data point associated with a lowest relative elevation of the set of first data points located in the portion; and generating, using the one or more computing devices, an elevation map wherein the elevation of each portion is based on at least the identified data point associated with the lowest relative elevation of the portion.