Dr. Jessica Allen
Sedimentation is one of the most common types of pollution in freshwater bodies, including rivers, streams and lakes. The negative impacts of high levels of sediment to organisms in the water are numerous, including destroying habitat for small animals, preventing larger animals from seeing their prey, suffocating fish, and blocking sunlight from reaching plants. Treating water with high concentrations of sediments is expensive, and water can still be left with an off flavor.
You don’t have to travel far to see the negative impacts of sedimentation. The Spokane River has been seriously impacted by many different types of pollution over the past century, including sedimentation. One major source of sediments for the Spokane River is Latah Creek, where upstream agricultural practices are washing large quantities of silt into the waterway. While it is clear that Latah Creek is a pollutions source for the Spokane River, what is less clear is just how much sediment is moving into the Spokane River and how it is moving in that body of water once it gets there.
How exactly is it possible to see how sediment moves through such a large river system? The short answer is drones.
Drones, unmanned aerial vehicles, aren’t only for hobbyists. They are frequently used in scientific research. Drones allow easy access to a bird’s-eye-view on landscapes, where they can be used for projects like tracking forest pests and predicting flooding. Research applications in wildlife management are also extensive, as drones provide some of the most accurate counts of animal populations.
Two EWU biology professors, Dr. Camille McNeely and Dr. Paul Spruell, along with graduate student Lily Cryster, are using a drone to track sediment flow from Latah Creek into the Spokane River. The aerial images they capture are used to monitor how much sediment flows out of Latah Creek, and the path it takes as it moves downriver. They will combine these data with water quality measurements to better understand how this sediment source affects water quality in the Spokane River. The project is funded by Rose Foundation’s Mike Chappell Fund for the Spokane River. By monitoring how sediments flow from Latah Creek into the Spokane River, EWU scientists hope to find solutions for cleaner water in our local river.
Below are images of sediment flowing from Latah Creek into the Spokane River take in March, 2019. Images were captured with the DJI Phantom 4 from 200 feet altitude.