The Poplar River Power Station is dependent on water from Cookson Reservoir for cooling. Power 

 plant operation is not adversely affected until reservoir levels drop below 749.0 metres. The dead 

 storage level for cooling water used in the generation process is 745.0 metres. The 2004 recorded levels 

 and associated operating levels are shown in Figure 3.19. 



2004 Cookson Reservoir 

 Daily Mean water Levels 



S 749 



Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec 



Figure 3.19 Cookson Reservoir Daily Mean Water Levels for 2004 and Median 

 Daily Water Levels, 1994-2003 



3.4.2 Water Quality 



The period from 1987 to 1993 saw very low volumes of surface-water runoff to Cookson Reservoir. 

 Consequently, total dissolved solids (TDS) in the reservoir increased steadily from approximately 780 

 mg/L to over 1,800 mg/L. Since 1993, higher runoff volumes have improved reservoir water quality. 

 Since 1997, the TDS levels in the reservoir have generally remained below 1,000 mg/L. The average 

 TDS level in Cookson Reservoir in 2004 was 967 mg/L, up slightly from the 2003 average level of 928 

 mg/L but still below past levels. 



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