The application is misrepresenting land elevations. Those should be elevation above sea level not the elevation above a body of water. For example, the eleven Finger Lakes in upstate New York USA are at very different elevations above sea level ( over 1,000’ to 280’) but those surface elevations are not shown. Between the lakes are hills that vary from one to several hundred feet above a lake. Keuka Lake at 714’ above sea level while the adjacent (about 8 miles apart) Seneca Lake is 444’ ASL. The hills between the lakes shows about 480’. We know that the hills in the immediate vicinity are about 500’ above these two lakes. The elevations of the land cannot be equated to two lakes to which they abut.
I suggest reconciling land elevations to sea level and including sea level notations for lake surfaces.