ALP 3

Contents
The plankton net funnel retained the vast majority of water while serving as a non -rigid structure
in effort to minimize any injuries associated with insertion. Two large plastic cups (without
bottoms) were stacked inside the bell mouth to improve its accessibility and increase its diameter
to where the bottom portion of the plankton net funnel (4.5 in) was slightly smaller than the
diameter of the modified bell mouth (5 in). To insert the fish embryos, a 10 ft x 1 in clear acrylic
hose was inserted several feet into the air bleeder valve port and the other end into the sample
bucket through the spout of the 5 -gal bucket lid. Cupping your hand over the spout and hose and
then blowing hard into the bucket through a small opening between your hand and the hose
created a reverse siphon and a water to water transfer of the rainbow trout embryos into the
reservoir discharge pipe. All groups of test specimens were inserted through the bell -mouth `y'
port starting with the smaller test fish, then larger test fish, and lastly the rainbow trout embryos.
Sleeve Valve Operation
Inserting the test sample is not possible while the discharge pipe is under pressure from the water
column of the reservoir. Prior to inserting the test sample, the 48 in butterfly valve immediately
upstream of the sleeve valve was placed in the closed position and then the sleeve valve was
opened slightly to release the pressure inside of this downstream section of the discharge pipe.
Therefore, the discharge pipe had to be depressurized to insert the test sample then slowly re-
pressurized once the sample was inside the discharge pipe. A 4 in steel pipe with two successive
4 in butterfly valves spaced about 2.5 ft apart connected the bottom of the discharge pipe
upstream of the butterfly valve to the bottom section of the discharge pipe upstream of the sleeve
valve and was used to slowly equalize water pressure between the two chambers. After the test
sample was inserted, the upstream 4 in butterfly valve was fully opened and then the downstream
butterfly valve slightly opened to where the pressurization became audible (figure 11).
Figure 11. Four inch steel pipe with two successive 4 in butterfly valves used to slowly equalize
water pressure between the two chambers.
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