Study of fish passage through culverts in Northeast Ohio

Written by STEM College student, Darshan Baral

A study has been carried out to analyze passage of 10 different fish species through culverts in Northeast Ohio. The goal is to determine the ratio of culverts that act as a barrier for fish passage and to identify design parameters which can be associated with passage success. The culvert data was provided by ODOT and data of discharge and stream morphology were obtained using online USGS repositories and GIS. Computer application FishXing was used to analyze passage of each fish species at 4 flow conditions (minimum average monthly flow, maximum average monthly flow, 2 year high flow, and 25% low flow). The results have shown that out of the 90 culverts, 23 culverts are partial barriers (some fish pass at some flow conditions) and 67 culverts are complete barriers (no fish pass at no flow condition). It is noteworthy that larger proportion of partial culverts was present in interstate routes as opposed to highway routes. Different standards adopted for culvert design in I-80 could be the possible reason behind this. The average slope of the partial barriers (0.6%) was found to be significantly (Student’s t-test, p < 0.05) less than the average slope of the complete barriers (1.6%). The results obtained from the study are expected to provide better understanding of the fish connectivity problem in Northeast Ohio. The employed study method is also anticipated to be usable in the future for analysis of additional culverts.