daily outflow (turbine dischai-ge only) from 

 March 13 through April 17 (fig. 9) was 424.4 

 c.m.s. ; the average daily inflow was 511.5 c.m.s. No 

 water was discharged through the spillway. Tliese 

 conditions resulted in gradual filling. Currents 

 were well oriented downstream at stations II and 

 III and reasonably so at station I. Downstream 

 orientation varied from 40 percent in the lower 

 part of the reservoir (station I) to 85 percent in 

 the upper part (station III). Velocities ranged 

 from zero at station I to 0.26 m.p.s. at station III. 

 Sustained minus 13.1^-m. level with spill. — The 

 reservoir was maintained near the minus 1.3.4-m. 

 level from April IS through May 22. The average 

 inflow was 731.7 c.m.s., and the mean spillway 

 discharge was 430.4 c.m.s. The rest of the inflow 



STATION 



was discharged through the turbines at Brownlee 

 Dam. 



The percentage of downstream currents at sta- 

 tions I and III increased considerably over that 

 of the pi-evious peiiod. Downstream orientation 

 increased from 4(1 to S2.fi percent at station I 

 and from 85 to 100 percent at station III (fig. 10). 

 The percentage of downstream currents at station 

 II <lecrea.sed from 68 to 49 percent. Some upstream 

 and cross- reservoir currents were also recorded at 

 this station. Velocities ranged from 0.015 m.p.s. 

 at station 1 to 0.21 m.p.s. at station III. 



Averages of curi'ents during 3 days separated 

 by 3-day intervals over a period of decreasing dis- 

 charge in 1964 are compared in figure 11. 



STATION II MILE 24 



STATION ill MILE 35 



Period 

 Pool status 

 Pool level 

 Inflow 



► Velocity m.p.s. 

 ■' Direction % of time 

 Downstream direction 



RESERVOIR CONDITION 

 May 23, 1964 

 Filling 



Minus 13.1m. 

 595 c. m.s. 



Spill discharge 371 c. m. s. 

 Total disctiarge 693 c.m.s. 



FiGUEE 11. — Direction (percentage of time, indicated by scale between center and uiiiht margin of eacli figure) and 

 average velocity (m.p.s., scale between center and lower margin) of currents recorded at .S-m. deptli in Brownlee 

 Reservoir for three 24-liour periods during rapidly decreasing di.-^charge at the 18.1-ni. level (May 23, 26, and 29, 

 1944). Direction of current reads toward iMjint of wedge. 



LIMNOLOGY OF BROWNLEE RESERVOIR 



319 



