The oil sands area is located in northeastern Alberta adjacent to the Canadian Shield (Fig. 1). The main drainage of the area is provided by the Athabasca-Clearwater system, the valleys of which are incised into a broad, muskeg-covered interior plain to depths of 200 to 300 feet. The tributary streams originate in three highland areas (Fig. 2): the Birch Mountains to the west of the Athabasca River which rise to about 2,700 feet, Stony Mountain south of Fort McMurray which reaches an elevation of 2,500 feet, and Muskeg Mountain to the east of the Athabasca River which rises gradually to 1,900 feet. To the southwest of the area, between Birch Mountain and Stony Mountain and north of the eastward flowing Athabasca River, is a subdued highland area with gentle slopes called the Thickwood Hills. These hills give rise to northward flowing tributaries of the MacKay River, and a few short streams flowing southward to the Athabasca.
A number of shallow lakes are located in the area, the largest and most numerous of which are located on the top of the Birch Mountains and form an interconnected chain of lakes, which flow into the Ells River. These are called Eaglenest, Gardiner, and Namur Lakes. The only lakes of any size south of Fort McMurray are Algar and Gregoire Lakes. McClelland Lake, which is located in the lowlands northeast of Bitumount, is an area of internal drainage.