- 15 - 



causes of these shortages have been severe ice conditions, beaver 

 activity, and miscommunication. 



On-demand releases have been made as requested during the ten-year 

 period. Inability to accurately control small releases from Cookson 

 Reservoir has occasionally resulted in an extension of the requested 

 release period. With the exception of 1981, when two consecutive 

 releases were made, each year' s on-demand release has been requested and 

 made in April or May of the following year. 



Figure 7 shows the recorded flow of the East Poplar River as compared to 

 the combined minimum flow and on-demand release volume as given in the 

 apportionment recommendation for 1981-90. 



12.000 



to 



Ld 

 DC 

 uj 10,000 



< 



o 



Ul 



Q 



o 



00 



=> 

 o 



DC 



< 



X 



o 



CO 

 Q 

 _J 



o 



8,000 - 



6,000 - 



4.000 - 



2,000 - 



29,000 



EZl RECOMMENDED MINIMUM FLOW AND RELEASE . 

 ES RECORDED 



1981 1982 1983 1984 1985 1986 1987 1988 1989 1990 



YEAR 



Figure 7. — Recorded discharge of the East Poplar River at International 



Boundary as compared to the total minimum flow recommendation. 



