Spot metering a mid-tone (partly shaded) area of the water, the fall foliage and other parts of the tree and grass/vegetation then averaging would be better than incident. Your 30d would be metering as a reflective meter by default, and likely in evaluative metering mode (thus, the algorithm of exposure follows the procedure of the Zone System). You could try incident reading from several angles, writing down each reading from each part of the scene, then averaging them all at the end. The problem with incident is that it assumes all parts of the scene are equal in luminance, when they are not, hence the purpose of a spot meter to measure each luminance independently. I am not, at all, a fan or exponent of metering scenes with digital cameras and extrapolating the result to film because it misses valuable learning in understanding how to meter critical parts of the scene to arrive at a correct exposure (although what constitutes "correct" is up to the photographer himself).