Stark Mountain stands within the watershed of Lake Champlain, which drains into the Richelieu River in Québec, the Saint Lawrence River, and then eventually into the Gulf of Saint Lawrence. On the east side of the ridge, Stark Mountain drains into Mill Brook, thence into the Mad River, the Winooski River, and into Lake Champlain. On the west side of the ridge, Stark Mountain drains into the Huntington River and into the Winooski River.