Dual-Camera, High-Resolution Aerial Assessment of Pipeline Revegetation

Authors: Booth, D; Cox, Samuel

Submitted to: Environmental Monitoring and Assessment
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 9/11/2008
Publication Date: 11/7/2008
Citation: Booth, D.T., Cox, S.E. 2008. Dual-Camera, High-Resolution Aerial Assessment of Pipeline Revegetation. Environmental Monitoring and Assessment 158:23-33.

Interpretive Summary: There is a U.S. Federal backlog for environmental monitoring of land disturbed by oil and gas pipelines—a result of laborious monitoring methods and fast-paced energy development. We conducted test aerial surveys over pipeline right-of-ways (ROWS) in which we intermittently, simultaneously triggered two cameras to obtain nested (one within the other) aerial photography having resolutions of 1 and 13 mm / pixel or 2 and 20 mm / pixel. (Compare these resolutions to the 30 m / pixel of Landsat satellite photographs.) Computer-facilitated methods were use to measure ground cover from the aerial photos and that was converted to diagrams showing where reclamation does not meet the revegetation standards agreed to by the pipeline companies. The study demonstrated that aerial monitoring can collect more data faster and less expensively than can be collected using conventional ground methods; and, it provides a photographic record along the entire length of the ROW.

Technical Abstract: Energy-extraction results in significant disturbance to rangelands in Wyoming and other western US states. Although reclamation is required by law, US General Accounting Office reports from 1999 and 2005 are clear that affected government agencies have—over much of the past decade—had difficulty accomplishing environmental monitoring mandated by the increase in extraction-related disturbance. We evaluated two pipeline rights of way (ROW) using nested images (1- or 2- with 13- or 20-mm ground sample distance (GSD)) acquired during Very Large Scale Aerial (VLSA) surveys. Aerial monitoring allowed for the collection of large numbers of geocoded samples, and for subsequent cover measurements using methods with demonstrated accuracy equal to that of conventional ground-based methods. Both pipelines had vegetative-cover deficiencies relative to their Plan of Development (POD) requirements. Using bare ground and ground-cover measurements from the higher-resolution imagery, we present a spatial representation of each pipeline ROW that allows quick identification of sections of the ROW that may need further reclamation action to meet POD standards. We also present aerial monitoring costs. We recommend VLSA pipeline surveys as a means for facilitating required environmental monitoring and for addressing the monitoring backlog that has developed with increased energy-extraction activity.