USACE LEVERAGES DRONE TECHNOLOGY TO CAPTURE IMAGERY AFTER FLOODING IN MIDWEST

BY CAPT. MIKE GLASCH, RYAN HIGNIGHT, Omaha District Omaha District

In mid-to-late March, floodwater covered much of eastern Nebraska, western Iowa, and northern Missouri. Due to the extreme amount of water in the area, members of the U.S. Army Corps of Engineers (USACE) Omaha District had trouble getting to the more than 500 miles of compromised levees to surveil for damage, so they turned to a new option to the Omaha District: drones.

Drones, or unmanned aerial systems (UAS), offer the district the opportunity to fly over affected levees and other flooded areas without putting district employees in danger.

“Anytime we send district personnel out to survey an area, there is a chance for something to happen ... be it getting stuck in the mud, fall into the water, or be affected by other hazards,” said Jon Kragt, Omaha District chief of Surveys, Mapping, and GIS. “Surveying by unmanned aircraft offers the district an expedient and accurate option to gather data that can very quickly be transferred to our district engineers to process.”

Drone aerial footage of repair work being completed at Union Valley Dike near Valley, Nebraska, after the 2019 runoff event. The flood event was due to water runoff from unregulated tributaries, which compromised more than 500 miles of levees along the Missouri River.

In addition to surveying levees, the district’s unmanned aircraft offer direct observation capabilities, photography, videography, measurement, inspections, surveillance, and 3-D modeling.

Dam or bridge inspections are also opportunities for drone usage. The pilot will fly a multi-rotor aircraft along the face of a dam or bridge, observing for cracks or other potential issues, removing the requirement for a person to do the same. Due to the deep water at a dam’s face, it can be timely and costly for a person to set up the equipment to observe the dam face. Utilizing an unmanned aircraft removes the person from the potentially dangerous situation. The aircraft pilot can stand safely away from the water to observe, and upon completion, there is photo and video evidence for people to reference.

The Omaha District currently owns and flies multi-rotor and fixed-wing aircraft. The multi-rotor aircraft, quad-copters, allow unmanned pilots the opportunity to fly smaller, tighter areas and still complete all of the missions previously mentioned. Battery life is shorter than that of the fixed-wing aircraft, but the multi-rotor gives the pilot the ability to hover and fly backward to closely observe the mission.

The fixed-wing aircraft fly faster and longer than the multi-rotors, so missions can be planned over a greater distance. A typical flight for a fixed-wing can cover more than 100 acres in just over an hour, dependent on weather and other mitigating factors, such as the weight of a camera. Because the fixed-wing aircraft generates its own lift across the wings, the battery life is extended when compared to that of a multi-rotor. However, missions can be larger than the battery life of either aircraft because both allow battery changes mid-mission.

“Through our computer, we continually monitor the aircraft during flight, especially the battery capacity. If battery power begins to drop, we will bring the aircraft back to the home waypoint, land it, and install a new charged battery,” said Jeff Cowman, district UAS pilot and aircrew training program manager. “After the install, we relaunch the aircraft, and send it to continue the mission it was already assigned and performing.”

The Omaha District UAS section continues to develop its program but hasn’t done it alone. When the flood occurred in March, the district reached out to USACE Headquarters Aviation for assistance. It was quick to respond, and within 24 hours of receiving Omaha’s request, Headquarters sent one of its own, as well as experienced pilots from across USACE – and additional aircraft to ensure the Omaha District was able to meet the flying requirements brought about by the flood.

“HQ Aviation’s quick actions helped the Omaha District UAS program get out in front of the flood recovery effort,” said Lt. Col. James Startzell, deputy district commander. “When weather allows for unmanned flights, the products provided to the district from the UAS team add great value to the levee rehabilitation program. There is still a lot of work ahead to fully realize UAS capabilities, and our team will continue to leverage the HQ UAS team whenever the mission calls for it.”

USACE has always been a leader in the use of advanced technology to get the job done, and as we usher in a new era, USACE is both “Building Strong” and flying strong.