The concentration of magnesium in the waters of Buffalo Creek ranges from nearly 0 to almost 15 milligrams per liter. The concentration is close to 0 for the first third of the creek's course, but then rises to two or three milligrams per liter. The magnesium concentration reaches its peak around halfway between the source and the mouth, then steadily declines to slightly under ten milligrams per liter at the mouth. However, one of Buffalo Creek's tributaries has a magnesium concentration of nearly 35 milligrams per liter.