Les Trois Lacs (''in English: The Three Lakes'') is a body of water shared between

Les Sources Regional County Municipality Les Sources () is a regional county municipality in the Estrie region of Quebec, Canada. The seat is the city of Val-des-Sources. Before April 22, 2006 it was known as Asbestos regional county municipality, and before August 1990 it was known as ...

, in

Estrie Estrie () is an List of Quebec regions, administrative region of Quebec that comprises the Eastern Townships. ''Estrie'', a French neologism, was coined as a derivative of ''est'', "east". Originally settled by anglophones, today it is about 90 pe ...

, and

Arthabaska Regional County Municipality Arthabaska Regional County Municipality () is a regional county municipality located in the Centre-du-Québec region of Quebec. Its seat is Victoriaville. Subdivisions There are 22 subdivisions within the RCM: ;Cities & Towns (4) * Daveluyvi ...

, in administrative region of

Centre-du-Québec Centre-du-Québec (, ''Central Quebec'') is a region of Quebec, Canada. The main centres are Drummondville, Victoriaville, and Bécancour. It has a land area of and a 2016 census population of 242,399 inhabitants. Description The Centre-du- ...

. The body of water, divided into three units by points and bays, is located on the course of the

Nicolet Southwest River The Nicolet Southwest River (''in French: rivière Nicolet Sud-Ouest'') is a tributary on the west bank of the Nicolet River. It empties into the municipality of Nicolet, in the Nicolet-Yamaska Regional County Municipality (MRC), in the adminis ...

Geography

Features

The Three Lakes have an area , long and , bordered by of rives. Acting as a sedimentation basin for the

, they have experienced a decrease in their volume since 1949. In 2004, the average depth was . From 1975 to 2004, the estimated average depth loss was 20%..

Hydrography

The Trois Lacs are 88% fed by the Nicolet Sud-Ouest river, while other small rivers and streams flow into it around its shores: the Second Ruisseau, the Monfette stream, the Trout stream and the Boutin watercourse. The median flow at the outlet varies between depending on the period of the year. The Three Lakes drain a watershed of , covering the municipalities of

Val-des-Sources Val-des-Sources (), meaning "Valley of the Springs", formerly known as Asbestos (), is a town on the Nicolet River in the Estrie (Eastern Townships) region of southeastern Quebec, Canada."Asbestos" in '' The New Encyclopædia Britannica''. Chic ...

, Saint-Rémi-de-Tingwick and Tingwick, which border the plan water, but also Saint-Adrien, Ham-Sud, Weedon, Dudswell, Saint-Camille, Saint-Georges-de-Windsor, Wotton and Danville. Two thirds of the watershed is occupied by forest; agriculture occupies 30% and urban vocations about 3%. The water quality is poor, with high concentrations of

phosphorus Phosphorus is a chemical element; it has Chemical symbol, symbol P and atomic number 15. All elemental forms of phosphorus are highly Reactivity (chemistry), reactive and are therefore never found in nature. They can nevertheless be prepared ar ...

. These concentrations, as well as those of other chemical compounds in lake water, indicate that they are in an advanced process of

eutrophication Eutrophication is a general term describing a process in which nutrients accumulate in a body of water, resulting in an increased growth of organisms that may deplete the oxygen in the water; ie. the process of too many plants growing on the s ...

, accelerated by activities of human origin: drainage, urbanization, agricultural practices and deforestation.

History

The body of water appears on a map by

Joseph Bouchette Lt.-Colonel Joseph Bouchette (; May 14, 1774 – April 8, 1841) was the Canadian Surveyor-General of British North America. His book, ''Topographical Description of the Province of Lower Canada'' was published at London in 1815 and also translated ...

in 1831 under the name . The name subsequently evolved into forms that reflect its tripartite topography, namely , and . The toponym "Les Trois Lacs" was formalized by the Government of Quebec on December 12, 1968..

References

External links

* * http://ville.asbestos.qc.ca/lac-trois-lacs-protection {{DEFAULTSORT:Three Lakes Lakes of Estrie Arthabaska Regional County Municipality Lakes of Centre-du-Québec Les Sources Regional County Municipality