The Methow's watershed is characterized by relatively pristine habitats, as much of the river basin is located in national forests and wildernesses.

The river was named after the Methow Native Americans (today part of the Confederated Tribes of the Colville Indian Reservation).

In 1811 David Thompson met the tribe living along the river and wrote their name as Smeetheowe.

Flowing from the west, the Twisp River drains the mountains south of Washington Pass as well as the eastern slopes of Sawtooth Ridge, a major mountain range with some of Washington state's highest peaks (such as Star Peak and Mt Bigelow).

In Robertson v. Methow Valley Citizens Council (a 1989 Stevens decision) the Rehnquist Court concluded that NEPA does not require a fully developed plan detailing what steps will be taken to mitigate adverse environmental impacts and does not require a "worst case analysis."

Translocation success was optimized by putting pairs of beavers together in man-made lodges that tended to keep them in the desired sites so that the beaver ponds would store rainwater, trap sediment and repair channel incision/erosion, serve as nurseries for salmonids and other species, and act as firebreaks in the fire-prone eastern Cascades.