Year Established: 2019 Start Date: 2019-05-29 End Date: 2020-05-28
Total Federal Funds: $25,256 Total Non-Federal Funds: Not available
Principal Investigators: Leroy F. Heitz
Abstract: Proper management of a regionâ€™s water resources requires water managers and water resources researchers to have accurate baseline information on the geomorphological and ecological health of surface water streams in a region. It is also vital to have a detailed baseline knowledge of potential pollution sources in groundwater recharge areas. Along with this baseline information there is also a need for periodic sampling of water quality indicators to identify changes in the environmental health of streams and groundwater recharge areas. Studies such as surface and ground water supply studies, depend on this kind of long term variable information to develop the best management practices for a regionâ€™s water resources. In the past, the only means of visual monitoring of stream and groundwater recharge areas health was either with direct on-ground monitoring or the use of high altitude satellite imagery or LIDAR (Light Imaging, Detection, and Ranging) data. This imagery and data was typically accurate to about 0.5-meter resolution. Because of the expense of data gathering, these resources were not available at intervals that could be used for the continued monitoring of the environmental health of Guamâ€™s streams and recharge areas. Recent advances in commercially available sUAS (Small Unmanned Aerial Systems) technology have made lower cost, highly accurate, sub- meter resolution aerial imagery available. Commercial sUAS drones fly at elevations less than 400 ft., capable of gathering high resolution data used for the development of georeferenced imagery on these low elevation flights. The photographs can be used as detailed high resolution individual photos of streams or groundwater recharge areas or can be composited into highly accurate georeferenced photos of various areas of study. Photogrammetric procedures allow foliage cover removal from the data to develop high resolution composite ground surface digital elevation models of areas of interest. The first phase of this project will involve the Completion of the installation and calibration of the EOS Arrow Gold differential correction (RTK) base station and antenna system at WERI. The second phase of the project will involve the calibration of the base station and extensive testing to be certain that rover coordinates gathered using differential corrections from the base station match coordinates used in base maps used in WERIâ€™s GIS system. The third phase will involve the aerial data gathering and development of georeferenced orthomaps and digital elevation models of test areas in North and South Guam. The detailed georeferenced aerial data will provide baseline knowledge on the location, size, and potential pollution sources in sinkholes located in the North Guam groundwater recharge areas. In South Guam, we will be able to accurately plot stream cross sections, determine erosion potential and possible sediment loading, and other sources of environmental contamination. Phase three will involve the development of a data management scheme for the imagery and other digital data gathered by the project. The data management scheme will be compatible with WERIâ€™s existing on-line water resources data retrieval system.