These lakes are less than 18' deep, have water with an alkalinity >100 ppm often causing a 'marl' or turquoise color, and have both an inlet and outlet, and the main water source is from streams.
Similar to soft water shallow drainage lakes, the submergent community of this lake type is often dominated by coon-tail (Ceratophyllum demersum), water-milfoils (Myriophyllum species), common waterweed (Elodea canadensis), and naiads (Najas species). However, muskgrasses (Chara species) that thrive in hard water are some of the most abundant species of aquatic plant in this lake type. Floating lilies (Nymphaea odorata and Nuphar variegata) are found near the shoreline in most examples. Fish species in headwater drainage lakes include northern pike, golden shiner, blacknose shiner, blackchin shiner, black bullhead, yellow bullhead, bluegill, largemouth bass, black crappie, and Johnny darter. Lowland drainage lakes within this type have these plus brook silverside, though the Johnny darter does not favor lakes that are very hard.
