Big Spencer Mountain is a mountain

Mountain

Image:Himalaya_annotated.jpg|thumb|right|The Himalayan mountain range with Mount Everestrect 58 14 160 49 Chomo Lonzorect 200 28 335 52 Makalurect 378 24 566 45 Mount Everestrect 188 581 920 656 Tibetan Plateaurect 250 406 340 427 Rong River...

 located in Piscataquis County

Piscataquis County, Maine

Piscataquis County is a county located in the U.S. state of Maine. In 2010, its population was 17,535, making it Maine's least-populous county. Its county seat is Dover-Foxcroft....

, Maine

Maine

Maine is a state in the New England region of the northeastern United States, bordered by the Atlantic Ocean to the east and south, New Hampshire to the west, and the Canadian provinces of Quebec to the northwest and New Brunswick to the northeast. Maine is both the northernmost and easternmost...

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Big Spencer Mtn. is flanked to the west by Little Spencer Mountain.

The southwest end of Big Spencer Mountain drains into Kidney Brook, thence into Lobster Lake, and into the West Branch

West Branch Penobscot River

The West Branch Penobscot River is a tributary of Maine's Penobscot River. The river flows from Seboomook Lake in Seboomook, Somerset County; the lake's principal inflows are the North Branch and South Branch Penobscot River...

 of the Penobscot River

Penobscot River

The Penobscot River is a river in the U.S. state of Maine. Including the river's West Branch and South Branch increases the Penobscot's length to , making it the second longest river system in Maine and the longest entirely in the state. Its drainage basin contains .It arises from four branches...

, and into Penobscot Bay

Penobscot Bay

Penobscot Bay originates from the mouth of Maine's Penobscot River. There are many islands in this bay, and on them, some of the country's most well-known summer colonies. The bay served as portal for the one time "lumber capital of the world," namely; the city of Bangor...

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The northeast end of Big Spencer Mtn. drains into Maxfield Brook, thence into Lobster Lake.
Part of the southeast side of Big Spencer Mtn. drains into Bear Brook, thence into Ragged Lake, Ragged Stream, Caribou Lake

Caribou Lake

Caribou Lake may refer to:* Caribou Lake , a lake in Temagami, Ontario, Canada* Caribou Lake , a lake in North Bay, Ontario, Canada* Caribou Lake , a lake in Northern California, USA...

, Chesuncook Lake

Chesuncook Lake

Chesuncook Lake is a reservoir in Piscataquis County, Maine, formed by the damming of the western branch of the Penobscot River in 1903 and 1916. It is approximately long and 1–4 miles wide, with a surface area of and a maximum depth of . It is the third-largest body of fresh water in Maine.In...

, Ripogenus Lake, and into the West Branch Penobscot River.
The southern part of the southeast side of Big Spencer drains into Lazy Tom Stream, thence into the Roach River

Roach River (Maine)

The Roach River is a river in Piscataquis County, Maine. From the outlet of Third Roach Pond in Shawtown , the river runs west, through Second and First Roach Ponds. The Roach River empties into Moosehead Lake, the source of the Kennebec River, in Spencer Bay .-References:**...

, and Moosehead Lake

Moosehead Lake

Moosehead Lake is the largest lake in the U.S. state of Maine and the largest mountain lake in the eastern United States. Situated in the Longfellow Mountains in the Maine Highlands Region, the lake is the source of the Kennebec River. Towns that border the lake include Greenville to the south and...

, the source of the Kennebec River

Kennebec River

The Kennebec River is a river that is entirely within the U.S. state of Maine. It rises in Moosehead Lake in west-central Maine. The East and West Outlets join at Indian Pond and the river then flows southward...

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