Aerial survey is a method of collecting geomatics or other imagery by using airplanes, helicopters, UAVs, balloons or other aerial methods. Typical types of data collected include aerial photography, Lidar, remote sensing (using various visible and invisible bands of the electromagnetic spectrum, such as infrared, gamma, or ultraviolet) and also geophysical data (such as aeromagnetic surveys and gravity. It can also refer to the chart or map made by analysing a region from the air. Aerial survey should be distinguished from satellite imagery technologies because of its better resolution, quality and atmospheric conditions (which can negatively impact and obscure satellite observation). Today, aerial survey is sometimes recognised as a synonym for aero-photogrammetry, part of photogrammetry where the camera is placed in the air. Measurements on aerial images are provided by photogrammetric technologies and methods.[1]Aerial surveys can provide information on many things not visible from the ground.
Ground surveys are performed in areas where new pipeline facilities are being considered. In some cases, these surveys are conducted adjacent to existing pipeline corridors. In other cases, when new greenfield pipelines are proposed, surveys will be conducted on various route possibilities, surveying a far greater number of properties within a much wider corridor than will actually be affected by the permanent pipeline easement. There are three types of ground surveys: civil,
environmental and cultural resource surveys.