Lakes that are large (>10 acres), deep (> 18 feet), soft (alkalinity < 50 ppm), and drainage have both an inlet and outlet, and the main water source is from streams.
The submergent communities in soft water deep drainage lakes are quite diverse and plants are abundant. Coon-tail (Ceratophyllum demersum), common waterweed (Elodea canadensis), and fern-leaf pondweed (Potamogeton robbinsii) occur abundantly, and several other pondweeds such as large-leaf pondweed (P. amplifolius), variable-leaf pondweed (P. gramineus), and small pondweed (P. pusillus) can be found in high-quality examples where water clarity is moderate to high. These diverse assemblages of aquatic macrophytes provide excellent habitat for fish, macro invertebrates, and other wildlife. Associated fish species include northern pike, rock bass, smallmouth bass, yellow perch, and cisco in very deep lakes.
