Mount Coe, ranked 22nd in height among Maine peaks, stands within the watershed of the Penobscot River, which drains into Penobscot Bay. The east side of Mt. Coe drains into a swampy area called The Klondike, then into Wassataquoik Stream, and the East Branch of the Penobscot River. The northwest and southwest sides of Mt. Coe drain into Nesowdnehunk Stream, then into the West Branch of the Penobscot River.