Integration of sUAS into Hydrogeophysical Studies

The small unoccupied aircraft systems (sUAS) sector is advancing rapidly through:

• miniaturization of aircraft and sensors;
• reduction in system purchase costs;
• increased performance, reliability, and stability; and
• easing of FAA flight restrictions.

This combination of factors is enabling increased use of sUAS as accessible, cost-effective, and safe tools for low-altitude deployment of scientific sensors.

Potential Value to Hydrogoelogic Field Studies

Integration of sUAS into groundwater studies will expand USGS capabilities to collect and use hydrologic information to improve our understanding of groundwater availability and quality:

• sUAS operations enable data collection in areas that might otherwise be difficult or impossible to access, such as unstable stream banks.
• Site reconnaissance with sUAS enables field personnel to quickly assess site conditions to inform placement of equipment or location of sampling and monitoring activities.
• sUAS surveys often can be conducted more rapidly than similar data collection on foot, potentially saving time and costs.
• Structure from Motion can generate high-resolution geo-referenced site imagery and 3D elevation models to inform and improve site conceptual, geophysical, and numerical models.
• Automation of georeferenced sUAS flights makes it easy to collect data from multiple sensors along the same transects and to conduct repeat observations of changing conditions over time.
• The lowercost of sUAS operations compared to traditional helicopter and plane surveys allows for collection of airborne data that might otherwise have been economically unfeasible for a given study.
• sUAS surveys can often provide more timely and higher resolution data than satellites.
• Deployment of sensors via sUAS rather than by foot, boat, or traditional aircraft may decrease USGS personnel exposure to hazardous field conditions.

Evaluation and Integration of sUAS

Thermal infrared image collected using a drone. In the image, the large yellow area in the upper left half is a stream, and the blue areas in the lower right are wetlands. The red area in the center of the image along the edge of the stream is relatively cooler groundwater discharging into the stream. The dark blue square is a ground control point, where the exact location is known and can be used to more accurately georeference the thermal imagery.

There is significant interest in the application of sUAS-borne scientific sensors to USGS hydrogeologic studies, especially groundwater/surface-water exchange studies. USGS is evaluating the potential for cost-effective, operationally feasible integration of sUAS-borne sensors into USGS hydrogeophysical studies.

Initial efforts are focusing on evaluation and demonstration of hydrogeologic data collection with natural color, multispectral, and thermal imaging sensors on small quadcopters. Longer term efforts include assessment of new and emerging sUAS geophysical sensors, such as ground-penetrating radar for bathymetry.

Policy and Background Information

Sensors and aircraft used by USGS must be approved for use by the USGS UAS Project Office and Department of Interior (DOI) Office of Aviation Services. USGS remote pilots are carded for operations by the Department of Interior and certified Remote Pilots under the Federal Aviation Administration's Part 107.

Photo of ground-penetrating radar (GPR) system (the white object mounted below the drone) being flown over a river in May 2019. The small multirotor drone used for the survey is also undergoing testing for the Department of Interior.

(Credit: John W. Lane, USGS. Public domain.)

Resources

USGS National Unmanned Aircraft Systems Project Office

U.S. Department of Interior Operational Procedures Memorandum (OPM) – 11: DOI Use of Unmanned Aircraft Systems (UAS)

U.S. Department of Interior/ Federal Aviation Administration Unmanned Aircraft Systems Certificate of Waiver or Authorization (COA): Operation of small Unmanned Aircraft System(s) weighing less than 55 lbs., in Class G airspace at or below 400 feet Above Ground Level (AGL) under the provisions of this authorization (2016-CSA-185-COA REV 1)

Federal Aviation Administration Unmanned Aircraft Systems