3.4 Cookson Reservoir 



3.4.1 Storage 



On January 1, 2004, Cookson Reservoir storage was 31,101 dam^ or 72% of the full supply volume. 

 The 2004 maximum, minimum, and period elevations and volumes are shown in Table 3.5. 



Spring inflows into the reservoir were well below normal in 2004. However, heavy rains during late 

 May and early June generated sufficient runoff to fill the reservoir. A release was initiated in May to 

 meet the recommended Poplar River basin demand release for the 2003-2004 apportionment year. No 

 releases were required to maintain the recommended apportionment target flow at the International 

 Boundary for the remainder of the year. 



In addition to runoff, reservoir levels were augmented by ground-water pimiping. Wells in the 

 abandoned west block mine site supplied 4,764 dam^ to Girard Creek. It is estimated that approximately 

 70% of this flow volume reached Cookson Reservoir. Wells in the soil salinity project area supplied 

 557 daml 



Table 3.5 Cookson Reservoir Storage Statistics for 2004 



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