30 



Elevation in 

 Meters 



755 

 753 

 751 

 749 

 747 

 745 

 743 

 741 



1996 Cookson Reservoir 



Daily Mean Water Levels 



Contents in 

 Cubic Decammeters 



Full Supply Level 



1996 Recorded 



=^ 



Median Level Minimum Desired OperaBna Level 



Minimum Useable Storage Level 



43400 

 29400 

 19100 

 11400 

 5860 

 2000 



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



Figure 3.15 Cookson Reservoir Mean Daily Water Levels for 1996 and Median Monthly 

 Water Levels for 1981-1991. 



3.4.2 Water-Quality 



The 1996 spring runoff had a positive impact on Cookson Reservoir water quality. At the end of 

 1996, boron concentrations in the reservoir were about 1.9 mg/L compared to about 2.4 mg/L at 

 the end of 1995. Similarly, TDS decreased from 1400 mg/L at the end of 1995 to about 1100 

 mg/L at the end of 1996. Water-quality conditions at the end of 1996 were similar to year end 

 conditions in 1989. 



■l.S Air-Oualitv 



SaskPower's ambient SOj monitoring for 1996 recorded no violations of SERM's hourly and 24 

 hour average standards at 0.17 and 0.06 ppm, respectively. The highest hourly value was 

 recorded at 0.1608 ppm in July, 1996. 



Total suspended particulate concentrations for 1996 obtained from SaskPower's monitor did not 

 exceed SERM's 24-hour standard of 120 ug/m?. The highest recorded concentration was 116.4 

 ug/m' in May, 1996. The geometric mean for the high-volume suspended particulate sampler was 

 14.6 ug/m^. 



