The Iowa Department of Natural Resources is in the midst of a program to create new maps of Iowa’s lakes. D.N.R. fisheries biologist, Mike Hawkins, says the new maps use sonar and global position satellite coordinates, but are not as detailed as they could be. Hawkins says the system they’re using is a single point sonar, so they get only one point off the bottom.
The system does pulse five or six times a second, but only of the one point, and he says there is some side-scan and multi-beam sonar they are looking at that gives a bigger picture of the lake bottom. Hawkins had a chance to see the other type of sonar at work during tests on West Lake Okoboji.
He says the sonar allows you to see things, as they found an old wooden boat at the bottom of the lake, a tire and an old snowmobile. The D-N-R has completed maps of 10 lakes and has scanned 44. Hawkins hopes they can use a more detailed sonar system in the future.
Hawkins says they hope as they look at some of the bigger lakes that they can justify using some of the new technology to get a more details picture than what they get now. One of the drawbacks of the more detailed technology is that it costs more. To see the new lake maps, go to the D-N-R’s website and click on the fishing link.