Tnnel 6 intake - Lake Mangaonui
Tunnel 5 outlet to Lake Mangaonui
Outley 0f Tunnel N. 3 to Lake Mangaonui

WATER LEVEL CONTROLLER


 
	Water Level Controller at inlet to canal at Lloyd Mandeno Forebay

From memory, the water level controller acts like a ballcock found in toilet cisterns.

The steel cylinder seen at the bottom of the controller floats on the surface of the canal. By a series of chains and levers it opens and closes the outlet gate from tunnel 6 to the canal leading to Lloyd Mandeno Power Station's forebay.

The water in the canal attains a reasonably constant level and thus the power station has a constant operating head.

Tunnel outlet into Lake Mangaonui

 

I am not sure which tunnel outlet this is into Lake Mangaonui.