ASCE has honored Kyle F. Flynn, Ph.D., P.E., M.ASCE, and Steven C. Chapra, Ph.D., F.ASCE, with the 2021 Samuel Arnold Greeley Award for the paper “Evaluating Hydraulic Habitat Suitability of Filamentous Algae Using an Unmanned Aerial Vehicle and Acoustic Doppler Current Profiler,” in the March 2020 issue of Journal of Environmental Engineering.
In the selected work, the researchers investigated the hydraulic habitat preference of the nuisance benthic alga Cladophora glomerata in a shallow river using an unmanned aerial vehicle (UAV) and acoustic Doppler current profiler (ADCP). Three separate ADCP surveys were completed over a 1-km channel segment during peak algal growth to correlate in situ velocity data with remotely sensed algal spatial cover. By pairing data from more than 60 transects and 3,500 ADCP ensembles, it was established that two distinct velocity distributions exist for Cladophora (p < 0.001). In algal-covered areas, the velocity profile averaged 0.67 m s−1, whereas it was found to be 0.41 m s−1 in uncovered locations. Groupings are considered to be optimal (former) and resource-limiting (latter) values. Corresponding shear velocities averaged 0.071 and 0.050 m s−1. An upper threshold perhaps also exists at which Cladophora will not colonize, but we were unable to quantify it in this study. Based on our findings, the integration of ADCP and remote sensing appears to be a worthwhile pairing for benthological study.
The Samuel Arnold Greeley Award is presented for papers on the design, construction, operation, or financing of water supply pollution control, storm drainage, or refuse disposal projects.