1. McNary Juvenile Fish Emergency Bypass System
July, 2011
Ryan Laughery – Hydraulic Engineer
US Army Corps of Engineers
BUILDING STRONG®

2. Location of Channel
The light blue section is the flow that the fish will follow when the emergency system is used. The dark blue is where the water flows under normal operation.

3. Section of Bypass System
Light blue boxes are the emergency bypass floor panels that need to be removed at unit 1 and 7 for the emergency bypass system to work.
The red box is where the dam-boards will be installed. Gray line indicates the direction of flow down the ice/trash sluiceway.

4. Section of Bypass System
Over view of the system with elevations.
The normal operating levels of the system is shown. The channel that the orifices flow into is at elevation 327.6
The sluice way is at elevation 320
The plunge pool is elevation 295.8
The water in the channel past the emergency bypass wall is at 279.0
Then into the tailrace.

5. Entrance to Sluiceway 5-6 ft deep and 5 to 6.5 fps
There are 4 openings in the floor, each consisting of three panels for a total of 12 panels to be removed. The fish will flow through the openings at a rate of 10 fps dropping 3 to 4 ft. Then the fish pass into the sluiceway where they will be in a channel 5 to 6 ft deep and running at 5 to 6.5 fps. The maximum travel is 1200 ft.

6. Sluiceway to Downwell Over Weir to Downwell 24 ft to 11 ft drop
Plunge depth of 24 ft to 36 ft
At the end of the sluiceway they will fall into a plunge pool. The pool will be 11 to 24 ft deep and have a drop height of 24.5 to 36 ft depending on flows through the system.

7. Plunge Pool in Downwell
Vertical Velocity of 1.2 to 2 fps
In the plunge pool they will experience a vertical/downward velocity of 1.2 to 2 fps.

8. Orifice Velocity of 12 to 18 fps
The velocity will speed up as they exit the plunge pool. They will experience a water velocity of 12 to 18 fps going through a 3’ to 12’ orifice opening.

9. Chute to Tailrace 300 ft long 21 ft wide flow at 3 to 4 fps
The water velocity will be about 3 to 4 fps and 21 ft wide at a depth of 5 to 6 feet. Either exiting over the end of the weir or through the orifice they will have a 8 to 15 ft drop in to the tailrace.

10. Enter The Tailrace Final step is a 8 to 15 ft drop to the tailrace
Drop into the tail race show in red here.