At some time in history a small dam was built just inside the tunnel and a pipe was placed under it to catch water. This pipe was connected to other pipelines just above Kanewai Dam #2. It is now turned off and no longer feeds the system which now only uses water from "sealed" tunnels to insure the purity of the water.
In the above photo you can see the pipe and in the one below you can see the valve that is now turned off and frozen that way.
