Question: Lake Arrowhead is an artificial lake in the towns of Waterboro and Limerick, in the state of Maine, the lake is an impoundment on the Little Ossipee River, which flows northeast to the Saco River in Limington, a town in which county, Maine, United States?

Context paragraphs:
Limington, Maine: Limington is a town in York County, Maine, United States.  The population was 3,713 at the 2010 census.  Limington is a tourist destination with historic architecture.  It is part of the Portland–South Portland–Biddeford, Maine metropolitan statistical area.

Little River (Ossipee River): The Little River is a 7.0 mi tributary of the Ossipee River in the U.S. state of Maine.  Via the Ossipee River, it is part of the Saco River watershed, flowing to the Atlantic Ocean.  The Little River flows entirely within the town of Cornish.

Dan Hole River: The Dan Hole River is a 5.1 mi long river in the town of Ossipee in eastern New Hampshire in the United States.  Its waters flow via the Beech River, Pine River, Ossipee Lake, the Ossipee River, and the Saco River to the Gulf of Maine, an arm of the Atlantic Ocean.

Broad Bay (New Hampshire): Broad Bay is a 431 acre freshwater lake located in Carroll County in eastern New Hampshire, United States, in the towns of Freedom and Ossipee.  Broad Bay is part of a chain of four lakes with identical water levels, due to a dam located downstream in Effingham Falls.  Upstream, a channel connects Broad Bay to Ossipee Lake, while a channel leads downstream through Leavitt Bay and Berry Bay to the start of the Ossipee River, which flows east into Maine and the Saco River.

Lake Arrowhead Reservoir: Lake Arrowhead is an artificial lake located in the San Bernardino Mountains on Little Bear Creek, a tributary of Deep Creek and the Mojave River.  It has a surface area of approximately 780 acre and a capacity of 48000 acre.ft .  It is surrounded by the unincorporated community of Lake Arrowhead in San Bernardino County, California.

Ossipee Lake: Ossipee Lake is located in Carroll County in eastern New Hampshire, in the communities of Ossipee and Freedom.  At 3257 acre , it is the sixth-largest lake located entirely in New Hampshire.  The lake is fed by the West Branch (entering from the north), the Bearcamp and Lovell rivers (entering from the west), and the Pine River (from the south).  Water leaves the eastern end of the lake via the Ossipee River, flowing to the Saco River in Maine.

Lake Arrowhead, Maine: Lake Arrowhead is a census-designated place (CDP) in the towns of Waterboro and Limerick in York County, Maine, United States.  The population was 3,071 at the 2010 census.  The CDP corresponds to the area covered by the Lake Arrowhead Community, a large subdivision begun in the 1960s which surrounds Lake Arrowhead, an artificial lake on the Little Ossipee River.  The community is part of the Portland–South Portland–Biddeford, Maine Metropolitan Statistical Area.

Lake Arrowhead (Maine): Lake Arrowhead is an artificial lake in the towns of Waterboro and Limerick in York County, Maine, United States.  The lake is an impoundment on the Little Ossipee River, which flows northeast to the Saco River in Limington.  Lake Arrowhead has a surface area of approximately 1100 acre .  It is surrounded by the large residential Lake Arrowhead Community.

Balch Pond: Balch Pond is a 577 acre water body located on the New Hampshire-Maine border, in the towns of Wakefield, New Hampshire, and Acton and Newfield, Maine.  A northwest portion of the lake in New Hampshire is known as Stump Pond.  Water flows from the eastern end of Balch Pond into the Little Ossipee River, a tributary of the Saco River.

Little Saco River: The Little Saco River is a 4.5 mi tributary of the Saco River in western Maine in the United States.  It begins at the junction of Haley Brook and Paine Brook in the northern part of the town of Brownfield and flows northeast, entering the town of Fryeburg just before its mouth at the Saco.

Supporting paragraphs: Lake Arrowhead (Maine) Limington, Maine
Answer: York County