The First Nation is a signatory to Treaty 9 (originally as part of the Fort Hope Band) and has reserved for itself the 831.50 hectares (2,054.7 acres) Neskantaga Indian reserve, containing the main community of Lansdowne House Indian Settlement on Attawapiskat Lake, on the west side of the lake, which is currently the community's water source.

Neskantaga is at the headwaters of the Attawapiskat River in the James Bay Lowlands, in a "pristine boreal setting known for bears, wolverines and excellent fishing" with many bodies of water and a "landscape weaving among them".

"[7] The "Attawapiskat and Otoskwin rivers surrounding Neskantaga merge into a delta with significant brackish tidal marshes" and the area was once "part of a major trade route".

[6] A 2020 CBC article described how the community members had given up their cabins, which were then demolished "for the promise of a better life at a new location with improved services, including clean running water in each house.

[12] The participation of the Neskantaga First Nation was further complicated by a forced evacuation in October 2020 caused by the community's "precarious water supply.

The lake often has a "naturally occurring “colour” from the roots of trees, plants and other organic matter" and has to be filtered before it can be used as drinking water.

[5] It is a "laborious process" in which individual households have to haul sleds several times a week to and from the local hotel to use the unreliable machine.

[14] East of Neskantaga and 90 kilometres (56 mi) west of Attawapiskat First Nation, in the Northern Ontario Ring of Fire, in the James Bay Lowlands, De Beers' Victor Diamond Mine—which was operational from 2009 until 2020 when it was decommissioned—had provided "clean water for hundreds of workers" on its open pit mining site.

[15][16] In 2016, then-Indigenous Affairs Minister Carolyn Bennett visited Neskantaga, which at that time had a population of 350, and announced that the federal government would "invest approximately $8.8 million to help upgrade the community's water treatment system, including an addition to the existing water plant with new treatment technology and additional reservoir storage capacity to meet the community's long-term needs.

"[17] In October 2020, the Neskantaga First Nation fully evacuated the reserve after test results showed high levels of hydrocarbons in the water supply,[18][19][20] caused by a faulty pump installed by Razar Contracting Services.