Question: The lake that is on the eastern boundary of the Chaubunagungamaug Reservation is also known by which name based on the town it's located in?

Context paragraphs:
Freedom, New Hampshire: Freedom is a town located in Carroll County, New Hampshire, United States.  The population was 1,489 at the 2010 census.  The town's eastern boundary runs along the Maine state border.  Ossipee Lake, with a resort and camps, is in the southwest of the town.

Lake Chaubunagungamaug: Lake Chaubunagungamaug, also known as Webster Lake, is a lake in the town of Webster, Massachusetts, United States.  It is located near the Connecticut border and has a surface area of 1442 acres.  Since 1921, the lake has also been known by a much longer name having 45 letters comprising fourteen syllables: Lake Char­gogg­a­gogg­man­chaugg­a­gogg­chau­bun­a­gung­a­maugg.

Cameia National Park: Cameia National Park is a national park in the Moxico province of Angola, located at about 1100 m above sea level.  It shares its name with the nearby municipality of Cameia.  The Cameia–Luacano road forms the northern boundary of the park with the Chifumage River forming the southern portion of the eastern boundary and the Lumege and Luena rivers the south-western boundary.  Much of the park consists of seasonally inundated plains that form part of the Zambezi river basin, with the northern half of the park draining into the Chifumage river.  There are also extensive miombo woodlands, similar to those in the Zambezi basin of western Zambia.  The park is a sample of nature not occurring elsewhere in Angola.  Two lakes, Lago Cameia and Lago Dilolo (the largest lake in Angola) lie outside the park boundaries and both have extensive reedbeds and grassy swamps that are rich in aquatic birds.

Lakeview, Mississauga: Lakeview is one of the communities in Mississauga (formerly Toronto Township), in the Region of Peel, just east of Port Credit, which amalgamated into the Town of Mississauga in 1968.  It is located in the extreme southeastern corner of the city.  Lakeview is found along the northern shores of Lake Ontario, with an eastern boundary of Etobicoke Creek north of Lake Shore Road and the property line of the former Small Arms Division of Canadian Arsenals Ltd./Marie Curtis Park south of Lake Shore Road, and a western boundary of Cooksville Creek.

Madge Lake: Madge Lake is located in eastern Saskatchewan, 18 km east of the town of Kamsack and just a few kilometres west of the province's eastern boundary.  It is centered near coordinates 51°40′ N, 101°38′ W. Road access to the lake is via Highway 57, which passes by the south shore of Madge Lake as it connects Highway 5 to Manitoba Highway 83.

Lady Robinsons Beach: Lady Robinsons Beach is the stretch of beach between the mouth of the Cooks River and the mouth of Georges River on the western shore of Botany Bay.  Originally the beach was known as "Seven Mile Beach".  The beach was renamed after the wife of the then Governor, Sir Hercules Robinson.  Isolated settlements separated from the beach by sand dunes were also given the name of "Lady Robinson's Beach" as their postal address.  Lady Robinsons Beach is the eastern boundary of the area known as the St George District.  It is also the eastern boundary of the Municipality of Rockdale and of the suburbs of Kyeemagh, Brighton-Le-Sands, Monterey, Ramsgate Beach, Sans Souci, Dolls Point and Sandringham.

Gilmanton Ironworks, New Hampshire: Gilmanton Ironworks (alternately Gilmanton Iron Works) is an unincorporated community in the town of Gilmanton in Belknap County, New Hampshire, in the United States.  It is located near the eastern boundary of the town, along a stretch of the Suncook River south of the outlet of Crystal Lake.  New Hampshire Route 140 runs through the village, leading east to Alton and west to the center of Gilmanton and then Belmont.

Chaubunagungamaug Reservation: The Chaubunagungamaug Reservation refers to the small parcel of land located in the town of Thompson, Connecticut, close to the border with the town of Webster, Massachusetts and within the bounds of Lake Chaubunagungamaug (Webster Lake) to the east and the French River to the west.  The reservation is used by the descendants of the Nipmuck Indians of the previous reservation, c. 1682-1869, that existed in the same area, who now identify as the Webster/Dudley Band of the Chaubunagungamaug Nipmuck.  Together with the Hassanamisco Nipmuc, both have received state recognition under the Massachusetts Commission on Indian Affairs.

Sagkeeng First Nation: The Sagkeeng First Nation is an Anishinabe First Nation which holds territory east of Lake Winnipeg in Manitoba, Canada 120 kilometers north of Winnipeg coordinates: 50°36′32″N 96°17′44″W.  The Sagkeeng Ojibway people are direct descendants of the Anishinabe tribes that migrated from one of the oldest settlements in North America in the Ontario Sault Ste. Marie area during the 1700s.  Sagkeeng, which was once called Fort Alexander, has a total population of approximately 7,600 registered band members with more than 1/2 of members living off reserve.  The name "Sagkeeng" is derived from the Ojibwe word "Zaagiing" meaning "at the outlet".  The Reserve is located on both North and South shores "at the outlet" of the Winnipeg River and lies adjacent to the northern border of the Rural Municipality of Alexander, which also borders the Town of Power view-Pine Falls.  The territory of Sagkeeng/Fort Alexander Reserve #3 originally, was to have commenced one mile upstream from the Fort Alexander trading post occupied by the Hudson’s Bay Company.  INAC files indicate the Chief and Council requested it be moved to its present location.  Had the boundaries not been moved the eastern boundary would have taken in all of Power-view and St. George.  The Manitoba Hydro Generating Station would also have been within this boundary.

The Long Water: The Long Water is a recreational lake in Kensington Gardens, London, England, created in 1730 at the behest of Queen Caroline.  The Long Water refers to the long and narrow western half of the lake that is known as the Serpentine.  Serpentine Bridge, which marks the boundary between Hyde Park and Kensington Gardens, also marks the Long Water's eastern boundary.

Supporting paragraphs: Chaubunagungamaug Reservation Lake Chaubunagungamaug
Answer: Webster Lake