Purchase a map that has GPS coordinates for structure, creek channels, humps, ETC marked and referenced in the index. You can pick up a hand held GPS pretty cheap these days, and use it in conjunction with the map(s). Then once you get in the general area, use your sonar to read the bottom.
We have placed cookies on your device to help make this website better. You can adjust your cookie settings, otherwise we'll assume you're okay to continue.