Peace-Athabasca Delta

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The Peace-Athabasca Delta is a large freshwater, inland delta in northeastern Alberta located where the Peace and Athabasca Rivers join the Slave River at the western end of Lake Athabasca.

Contents 1 Conservation 1.1 Influence of Bennett Dam 2 Waterways 3 References

[edit] Conservation

The marshes, lakes and mud flats of this area are an important habitat for waterfowl nesting and provides a staging area for migration.^[1] As many as one million ducks, geese and swans pass through this area in the fall. The grass and sedge meadows of this area provide habitat for several thousand Wood and Plains Buffalo. The endangered Whooping Crane migrates through the delta on its way to its nearby nesting area.

Much of this area falls inside Wood Buffalo National Park. This delta was recognized on 24 May 1982 as a wetland of international significance under the Ramsar Convention, for its undisturbed nature and for being the largest boreal delta of the world.^[2]

[edit] Influence of Bennett Dam

A significant change to the water flow through the delta occurred as a result of the construction of the W.A.C. Bennett Dam in northern British Columbia by BC Hydro, a major hydropower utility. Initial drops in water levels were mitigated by the construction of three rock-fill weirs on the Chenal des Quatre Forches, Revillon Coupé, and Riviere des Rochers, the first of which was later removed due to complaints from muskrat trappers. While the weirs restored mean open-season water levels nearly to pre-regulation levels, they had no effect on the spring ice-jam floods that play a critical role in refilling perched basins and wetlands outside of the permanently connected channels and lakes. As a result, the Peace-Athabasca Delta is substantially drier than it was prior to regulation. It should be noted, however, that climatic factors may also play a large role in this drying, since nearby areas unaffected by the Bennett Dam have also dried substantially in recent years. An ongoing lawsuit between BC Hydro and local First Nations bands relates to the effects of Bennett Dam on Delta water levels and associated traditional lifestyles.

[edit] Waterways

The Birch River flows into Lake Claire, the largest lake completely in Alberta, which is an important part of the delta. Other lakes developed in the region are Baril Lake, Mamawi Lake, Hilda Lake, Otter Lake, French Lake, Pair Lakes, Welstead Lake, Four Forks Lake, Galoot Lake, Pushup Lake, Jemis Lake, Richardson Lake, Flett Lake, Blanche Lake and Limon Lake.

The waterway connecting Lake Athabasca and the point where Peace River flows into the Slave River is called Riviere Des Roche.

Other rivers draining the wetlands through the Peace-Athabasca Delta include Swift Current Creek, Carolyn Creek, Modere Creek, Steepbank River, McIvor River, Buckton Creek, Frog Creek, Sall River, Bolton Creek, Edra Creek, Peel Creek, Alice Creek, Mamawi Creek, Embarras River, Horse Island Creek, Chilloneys Creek, Claire River, Dempsey Creek, Baril River, Peltier Creek, Scow Channel, Powder Creek, and Revillon Coupe.

[edit] References