STREAMSCOPE: FIXED-MOUNT LASER SCANNING INSTRUMENTATION FOR REMOTE STREAM GAUGING IN SHALLOW RIVERS WITH FREQUENTLY CHANGING GEOMORPHOLOGIES

Abstract

Accurate streamflow monitoring in shallow rivers with frequently changing geomorphology poses a unique challenge, particularly in remote and ungauged locations. This thesis presents a novel approach developed in collaboration with the United States Geological Survey (USGS) to generate real-time discharge estimates using a low-power, non-contact sensor system. StreamScope integrates a Class II 620 nm laser rangefinder with an ultrasonic sensor to remotely measure river cross-sectional geometry and develop stage–area ratings. Through onboard automation, the system captures highresolution bathymetric data, enabling continuous discharge estimation without physical contact with the stream. Laboratory experiments were conducted to evaluate the selected laser rangefinder under varying conditions of solar radiation, water turbidity, water depth, bottom substrate, and sensor height. The results demonstrated that the unit operates best under low solar radiation, is capable of obtaining measurements under low turbidity up to 20 NTU, and that the laser’s returns may serve as a proxy for turbidity. Additionally, the tests established the operational limits of the sensor. The field deployment at Falls Creek in Davis, Oklahoma, demonstrated the robustness and precision of the instrument in a dynamic, real-world environment. The data collected provided a significant improvement in resolution compared to a traditional USGS stream survey.