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NUPO 2012 Research Missions


Monitor River Impacts During Removal of Elwha and Glines Dams

Olympic National Park in Washington
GoPro Hero2 image of Lake Aldwell taken by a UAS at 200 feet
GoPro Hero2 image of Lake Aldwell taken by a UAS at 200 feet

The Elwha River Restoration Project, led by the National Park Service (NPS), was established to produce a scientifically sound technical narrative describing what happened to the fish, reservoir sediment, and reservoir topography, and vegetation during and following dam removal. This restoration project is unique since the removal of the Elwha and Glines Canyon Dams represents the largest controlled release of sediment in the history of North America and encompasses an entire watershed. This entire area includes 320 square miles, from Olympic Mountains to the Strait of Juan de Fuca, of predominantly pristine wilderness that is also historically home to all runs of Pacific Northwest salmon. Fully understanding the physical and biological responses of this river system to dam removal will provide invaluable information needed for other dam removal river restoration projects, as well as any dam operations undergoing Federal Energy Regulatory Commission (FERC) relicensing.

As part of this restoration effort a sUAS mission was performed along the Elwha River as a collaborative effort between the USGS, the Bureau of Reclamation, and the NPS. The focus of this mission, which occurred in June and September 2012, was the use of repeated sUAS surveys to acquire data that, once orthorectified, would provide information about the rates and patterns of change that occur during this large scale river restoration. Since this is the first dam removal on such a large scale, there are uncertainties about how rapidly, and in what patterns, sediment will erode from the reservoirs and move downstream. The hope is that many of these uncertainties can be addressed by using remotely sensed data to monitor changes in the reservoirs and river channel. It was believed that the resolution of imagery, and if available Ku band radar imagery, collected from sUAS technology would be highly valuable for monitoring sediment volumes eroded from the reservoir and deposited downstream, where the mobile sediment can potentially affect salmon habitat and flood-stage elevation.

Rectified Orthomosaic generated from UAS acquired data
Rectified Orthomosaic generated from UAS acquired data
Elevation Model generated from UAS acquired data
Elevation Model generated from UAS acquired data

After the imagery data was acquired, it was used in a systematic process of geometric correction and three-dimensional reconstruction to generate a river model over the Lake Aldwell area. Specific data processing steps included selecting, loading and aligning the images, point cloud creation with horizontal and vertical derivations, elevation modeling and draping of the images, and export of the geographic products. As a result of this processing an orthorectified imagery base of the reservoir, showing the restored river basin with the rapid change in sediment movement and infill, was created. Combining this base imagery with other remotely sensed data types, provides a multi-layered historical collection of data over the area that can be used to evaluate sediment movements. Documenting this information will also benefit future efforts since what is learned from the Elwha River changes can be used as a guide during other dam removal projects in the Pacific Northwest and nationwide.

Study Points of Contact:
Douglas R. Clark, Ph.D., Bureau of Reclamation, TSC
drclark@usbr.gov

Andrew Ritchie, U.S. Geological Survey
aritchie@usgs.gov

Abandoned Mine Lands (AML) Inspections

Coal Basin Mine in Putkin County Colorado
Elevation model and 500 foot contours derived from UAS collected GoPro Hero2 imagery
Elevation model and 500 foot contours derived from UAS collected GoPro Hero2 imagery

Abandoned mines can pose serious health and safety hazards, such as landslides, erosion, surface instability, and burning coal refuse, which is why the government is required to inspect Abandoned Mine Land (AML) sites and identify any needed remediation. This means that State and Federal AML departments must spend significant amounts of time and money driving to remote sites through rough terrain in order to perform these inspections. Therefore, in September 2012 a proof of concept mission was performed to determine if the Raven sensors could be used to record the area and identify any AML features, such as portals and other dangerous openings. The ability to use Raven data to perform thorough site inspections would significantly decrease the time and expense needed, as well as help inspectors determine the best course for any needed remediation.

This mission was performed by the USGS National UAS Project Office, in cooperation with the Office of Surface Mining, at the Coal Basin mining operation, Pitkin County, Colorado. The topographic basin where the mine facilities were located covers 236 acres and is on the divide that separates the North Fork of the Gunnison watershed from the Crystal River watershed, and drainage from the east side of Huntsman Ridge flows through several tributaries into Coal Creek. All mine portals and surface facilities in the basin are located in Pitkin County, primarily within the White River National Forest, with some interspersed private lands. The underground mine areas extended to the west under Huntsman Ridge into Gunnison County.

Mining of the Coal Basin deposits began in 1895 and continued until 1908, and then in 1956 the Mid-Continent Resources began producing coking coal at this location. The Coal Basin Mine consists of five adjacent underground mines, a rock tunnel entry, a preparation plant, two coal waste piles, one development waste pile, an extensive road system and numerous ancillary facilities. There were five drift mines, driven from the outcrop down-dip through the western flank of Coal Basin and under Huntsman Ridge, that were all interconnected. Coal, men and equipment were brought to the surface through one bore of the rock tunnel. The Coal Basin area also has diverse climate characteristics caused by its precipitous rise in elevation, the lowest point was the coal preparation plant at 8,000 feet, while the highest point is along Huntsman Ridge at 11,852 feet. As a result, temperature, precipitation, and wind conditions are quite variable throughout the disturbed area.

During this mission a GoPro Hero 2 camera mounted on the Raven was used for the first time. After successfully acquiring this new imagery, it was later evaluated for use in 3D photogrammetric modeling software. As a result it was determined that this type of image data provided a better way to use structure from motion techniques.

Overall, this mission successfully demonstrated the value of utilizing sUAS technology with mounted cameras to assist in the extremely vast and difficult job of monitoring and inspecting AML areas. Several technical advances were also shown as part of this mission including the ability to use a retrofitted camera on a Raven and the ability to fly at elevations above 10,000 feet, which is very important to support the many high elevation DOI lands in the western United States.

Study Point of Contact:
Sandy Brown, Senior Environmental Protection Specialist
Colorado Division of Minerals and Geology
sandy.brown@state.co.us