Outlet towers are found in reservoirs,
usually near to the dam. The tower sits above an outlet pipe
or tunnel used to transport water out of the reservoir.
It is built to house controls for opening and closing valves
or gates
that control the flow of water through the outlet. The controls
are normally located inside in a room at the top of the tower.
The outlet tower and shaft spillway
under construction for Roadford Dam in Devon, SW England. The
outlet tower is the one on the left.
The tunnel leading away from the
two towers houses the outlet pipe
In
a reservoir for water supply, a tower will often have a vertical
pipe inside with a number of horizontal pipes leading into it
from the reservoir. The horizontal pipes are used to draw-off
water from different levels in the reservoir. Water is let into
them by opening valves at their entrances. The vertical pipe
then connects to a horizontal pipe that takes the water away
from the tower through a tunnel to the water treatment works.
Cross-section
through an outlet tower
The vertical pipe
in the
outlet tower in Wimbleball
lake in Somerset,
SW England
Where a tower is used to control water
supply to a hydroelectric power station, there is only one inlet
for the water. These towers are called intake towers.
