Meramec River

The Meramec River is one of the longest free-flowing waterways in Missouri, draining 3,980 square miles (10,300 km2) while wandering 218 miles (351 km) through six Missouri Ozark Highland counties: Dent, Phelps, Crawford, Franklin, Jefferson, and St. Louis, before it empties into the Mississippi River at Arnold and Oakville, Missouri. Between its source and its mouth, it falls 1,025 feet (312 m). The Meramec watershed covers portions of eight additional counties—Maries, Gasconade, Iron, Washington, Reynolds, St. Francois, Ste. Genevieve, and Texas—totaling approximately 3,980 square miles (10,300 km2). Year-round navigability begins above Meramec Spring, just south of St. James. The Meramec's size increases at the confluence of the Dry Fork, and its navigability continues until the river enters the Mississippi at Arnold, Missouri.