The Liard River originates in the southern portion of the Yukon Territory (Figure 1). The river flows southeast across the British Columbia border, past the town of Liard River. Then, the Liard flows north across the Northwest Territories border to the confluence with the South Nahanni River and continues northeast, where it joins the Mackenzie River. The Kechika River comes from the south and meets the Liard 70 km upstream from the town of Liard River. Other major tributaries which are further downstream include the Fort Nelson and Petitot Rivers from the south. The Liard River is under ice from November to April.
There are three water quality monitoring stations on the Liard River (Upper Crossing in the Yukon, Lower Crossing in British Columbia, and Fort Liard in the Northwest Territories - see Figure 1). The Lower Crossing monitoring station is located at Mile 496 of the Alaska Highway at the lower Liard bridge crossing. The water quality of the other two stations is discussed in two separate reports (Jang & Pommen, 1996a & 1996b). Mining activities on the Liard are concentrated upstream near the Dease and Kechika Rivers. Forestry in the Liard River basin occurs in the Yukon and British Columbia. Plans for a hydroelectric project downstream from the town of Liard River and near the Beaver River confluence exist, but are not expected to proceed within the next twenty years (MacDonald, 1993).
Data for this report are from sampling by Environment Canada, between 1984 and 1994, and are stored under ENVIRODAT station number BC10BE0005. The water quality indicators are plotted in Figures 3 to 42. Water Survey of Canada operated a flow gauge at the water quality monitoring station (site number BC10BE001). The drainage area at the flow station is 104,000 km2. Flow data are graphed in Figure 2.