At the center of the North American continent, Minnesota contains three great watersheds, areas of land from which all surface water eventually flows into a single stream. From these watersheds, water runs in three directions to three different seas: in the largest, water flows south through the Mississippi River and its tributaries to the Gulf of Mexico; from northeastern Minnesota and its St. Louis River system, water drains eastward into Lake Superior and moves through the Great Lakes to the Atlantic Ocean; and in northwestern Minnesota, water flows north by way of the Red River of the North and the Rainy River into Canada’s Lake Winnipeg and on to Hudson Bay. These three areas have very different physical features. The St. Louis River watershed is rough, hilly, and heavily wooded, with many streams that have swift currents, abound with waterfalls, and rarely overflow their steep, rocky banks. The watershed of the Red River of the North lies largely on flat prairie land, where riverbanks are low and currents sluggish. Minnesota’s north-flowing streams are especially prone to spring flooding when runoff from melting snows and warm rains in the southern part of the watershed reaches northern areas still frozen over or clogged with ice flows. The Mississippi watershed combines features of the other two: its upper portion is generally heavily forested, with rolling terrain and swift streams, while farther down currents slow as streams meander through open prairies, where they may overflow their banks in times of high water. Since 1909, state and federal agencies have been charged with regulating Minnesota’s waters, and watershed districts today oversee such activities as water supply, drainage, flood control, and pollution control to help conserve Minnesota’s abundant water resources for present and future generations.