Authors: Geoffrey Fouad*, Monmouth University
Topics: Field Methods, Higher Education
Keywords: lake, bathymetry, surveying, education, New Jersey
Session Type: Paper
Start / End Time: 10:00 AM / 11:40 AM
Room: Studio 4, Marriott, 2nd Floor
Presentation File: No File Uploaded
Lake Como is a 37-acre lake next to the Atlantic Ocean in Monmouth County, New Jersey. The lake has been the source of flooding in the surrounding community. Bathymetric surveys should be conducted on a regular basis to plan dredging projects. However, professional surveys based on sonar can be expensive. A cheaper alternative would be to develop a summer field course in which students of nearby Monmouth University use tape-down measurements to map the bottom of Lake Como. The tradeoff is fewer survey points, but this may not be a problem if the bottom of the lake is relatively flat. A sonar survey of Lake Como was conducted including over 6,000 points. The survey points were progressively and randomly thinned to mimic a tape-down survey. Repeated random samples were used to generate bathymetric surfaces, estimate the volume of the lake, and conduct statistical testing. Results indicate that only 45 points distributed in a 60-m sampling grid produce volume estimates within 5% of the sonar survey at 95% confidence. The same number of points generated bathymetric surfaces with an average difference of less than 0.1 ft from the sonar-based surface. These results suggest a tape-down survey could be a reasonable substitute for a sonar survey. A summer course could be developed to teach field mapping techniques. The course would produce annual bathymetric maps of Lake Como to inform dredging projects and study sedimentation rates.