Upper Klamath Lake
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Upper Klamath Lake (sometimes called Klamath Lake) is a large, shallow freshwater lake east of the Cascade Range in south central Oregon in the United States. The largest freshwater body in Oregon, it is approximately 20 mi (32 km) long and 8 mi (12.9 km) wide and extends northwest from the city of Klamath Falls. It sits at an elevation of 4140 ft (1262 m).
The lake depth fluctates due to regulation of its water supply, ranging from 8 ft (2.5 m) to 60 feet (18 m) deep at average levels. It is fed by several streams, including the Williamson River and is drained by the Klamath River, which issues from the south end of the lake. It is connected by short channel to the smaller Agency Lake to the north. The Upper Klamath National Wildlife Refuge sits along the north edge of the lake.
History
Since 1917, the water level in the lake has been regulated by the United States Bureau of Reclamation as part of the Klamath Reclamation Project to support irrigation in the valley south of the river.
Prior to the 20th century the lake was surrounded by widespread marshes which were largely drained for cultivated land. The lake is naturally eutrophic, resulting in a high natural concentration of nutrients. In the 20th century, the augmentation of nutrients by agricultural runoff in the surrounding farming valley have caused the lake to become hypereuthrophic resulting in blue-green algae blooms over the lake ( largely Aphanizomenon flos-aquae) The algae blooms turn the water an opaque green in the summer and afford little recreational use on the lake. State standards for dissolved oxygen are routinely violated. In 1988, two formerly abundant Upper Klamath Lake fish species, the Lost River sucker and the shortnose sucker (Catostomidae), were placed on the federal endangered species list.
A drought in the summer of 2001 caused the Bureau to shut down the Klamath Project to protect the sucker population. The shutdown lead to widespread protests among the ranching community and has become a national issue concerning property rights and environmentalism.
External links
- USGS: Upper Klamath Lake nutrient study (http://or.water.usgs.gov/projs_dir/pn381/pn381.html)
- Oregon Lakes: Upper Klamath Lake (http://www.oregonlakes.org/gallery/klamath/klamath.html)
- Klamath Falls Herald and News, July 1, 2003: All Eyes on Upper Klamath Lake (http://www.propertyrightsresearch.org/articles/all_eyes_are_on_the_upper_klamat.htm)ja:アッパークラマス湖