Tetapaga Lake, also known as Lake Tetapaga, is a narrow east-west trending 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 Temagami region of Northeastern Ontario

Northeastern Ontario

Northeastern Ontario is the region within the Canadian province of Ontario which lies north and east of Lakes Superior and Huron.Northeastern Ontario consists of the districts of Algoma, Sudbury, Cochrane, Timiskaming, Nipissing and Manitoulin; and the single-tier municipality of Greater...

, Canada

Canada

Canada is a North American country consisting of ten provinces and three territories. Located in the northern part of the continent, it extends from the Atlantic Ocean in the east to the Pacific Ocean in the west, and northward into the Arctic Ocean...

, located at the abandoned iron

Iron

Iron is a chemical element with the symbol Fe and atomic number 26. It is a metal in the first transition series. It is the most common element forming the planet Earth as a whole, forming much of Earth's outer and inner core. It is the fourth most common element in the Earth's crust...

-bearing Sherman Mine

Sherman Mine

Sherman Mine is a large abandoned open pit mine in Temagami, Ontario, Canada. It was a major producer of iron ore. The mine was the source of a multi-ton boulder of banded iron formation and was mined from 1967 until 1990 by Cleveland-Cliffs Iron Company...

. A gravel road crosses the central portion of the lake, splitting it into two small lakes. The eastern half of Tetapaga Lake is somewhat green in colour due to acid mine drainage

Acid mine drainage

Acid mine drainage , or acid rock drainage , refers to the outflow of acidic water from metal mines or coal mines. However, other areas where the earth has been disturbed may also contribute acid rock drainage to the environment...

 water flowing into the lake. The acid mine drainage water results from water seeping through the abandoned iron ore of Sherman Mine along its eastern shore. Its western half is relatively uninfected where very little waste from Sherman Mine exists.