Borax Lake is a small alkali lake

Lake

A lake is a body of relatively still fresh or salt water of considerable size, localized in a basin, that is surrounded by land. Lakes are inland and not part of the ocean and therefore are distinct from lagoons, and are larger and deeper than ponds. Lakes can be contrasted with rivers or streams,...

 in the arid Pueblo Valley of southeastern Oregon

Oregon

Oregon is a state in the Pacific Northwest region of the United States. It is located on the Pacific coast, with Washington to the north, California to the south, Nevada on the southeast and Idaho to the east. The Columbia and Snake rivers delineate much of Oregon's northern and eastern...

, United States

United States

The United States of America is a federal constitutional republic comprising fifty states and a federal district...

 near Fields, Oregon

Fields, Oregon

Fields is a small unincorporated community in Harney County, Oregon, United States, located south of Burns.In 2000, the community had a population of 86, including 17 students through grade 8. The average age was 38; the average household size was 2.53 persons; the average household income was...

. The lake is fed by an underground geothermal

Geothermal

Geothermal is related to energy and may refer to:* The geothermal gradient and associated heat flows from within the Earth- Renewable technology :...

 well with a temperature of around 190°C. The lake contains high concentrations of sodium borate (hence the name) and arsenic

Arsenic

Arsenic is a chemical element with the symbol As, atomic number 33 and relative atomic mass 74.92. Arsenic occurs in many minerals, usually in conjunction with sulfur and metals, and also as a pure elemental crystal. It was first documented by Albertus Magnus in 1250.Arsenic is a metalloid...

, the latter fatal to humans, and has a mean temperature of around 30°C. Despite this, it is home to a unique species of chub, known as the Borax Lake chub

Borax Lake chub

The Borax Lake chub Gila boraxobius is a rare cyprinid fish found only in outflows and pools around Borax Lake, a small lake of the Alvord basin, Harney County, Oregon....

. The species is threatened by nearby development of geothermal power

Geothermal power

Geothermal energy is thermal energy generated and stored in the Earth. Thermal energy is the energy that determines the temperature of matter. Earth's geothermal energy originates from the original formation of the planet and from radioactive decay of minerals...

resources. The lake, along with its surrounding wetlands, are sufficiently warm enough so that they do not freeze during the winter. This makes the lake an important bird habitat year-round.