Uncertainty-aware geospatial system for mapping and visualizing underground utilities

Underground utility lines being struck is a long-standing problem worldwide, causing public service disruptions, project delays, cost overruns, property damage, injuries, and fatalities that cost billions of dollars each year. Utility strikes are attributed to two main causes: the lack of reliable data regarding the true locations of underground utilities and the lack of an effective means to communicate the inherent uncertainties associated with utility location data to end-users (e.g., excavator operators). Inaccurate utility location information leads to falsely instilled confidence and potentially misleads equipment operators into unintentional utility strikes. There is a great need to map underground utilities and to model and communicate uncertainties to end-users for safe excavations. This paper presents a geospatial system for mapping and uncertainty-aware visualization of underground utilities. Ground penetrating radar (GPR), global positioning system (GPS), and geographical information system (GIS) are integrated into a total 3G system for geospatial utility data collection. Field experiments are conducted to assess the locating accuracy of the system and reveal the patterns of positional errors. Three-dimensional (3D) probabilistic uncertainty bands that enclose the true utility line with specific probabilities are developed to handle the positional uncertainties of underground utilities. Multipatch surface models are adopted to visualize the 3D uncertainty bands in GIS to communicate both the locations of utilities and the associated uncertainties to end-users. The geospatial 3G system, together with the proposed 3D probabilistic uncertainty bands, enables the mapping and visualization of some underground utilities in a non-destructive and uncertainty-aware manner to avoid disastrous utility strikes and promote safe excavations. (C) 2015 Elsevier B.V. All rights reserved.