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The exit channel prgram outlines the dimensions of the exit channel which carries water from the sedimentation tank to the distribution tank where. Chlorine in the is added to the water at the end of the exit channel before it enters the storage tank.
The exit channel program calculates three pieces of the design. It determings the dimensions of the exit channel it self, the size of the outlet weir, which controls flow to the storage tank and the plant water level, and the size and length of the sedimentation launders.

Exit Channel Dimensions

The length of the exit channel is found first. The channel is defined to span perpendicular to the sedimentation tanks, and thus its length must always be the total width occupied by all sedimentation tanks. The equation used is listed below.

Equation 1 - L.ExitChannel

The width of the exit channel is defined to be the same as the width of the inlet channel.

The depth of the exit channel is found at the end of the program after the head loss through the sedimentation tank launders can be determined.

Exit Weir Specifications

The exit weir, which controls the flow of water leaving the plant also regulates the water heights in the plant. The weir is a large diameter pvc pipe that functions freefall overflow weir. The equation used to determine the pipe size necessary is a deriviative of the fluid dynamics sharp crested weir equation. The equation was such that the length of the weir, over which water flows is the circumference of the pipe and the equation calculated the diameter of the pipe necessary for that length. The equation used can be found below.

This component must maintain some dimensional consistency with the other components of the plant. It consists of having inlet pipes that connect to each sedimentation tank, and a circular weir in the center that will transport the water to the storage tank. It is in the weir where water will be chlorinated.
The height of the leveling tank's wall will be the same as the height, measured from the platform of the plant, as the wall for the channel and the sedimentation tank, which is 70 cm.
The water level in the PLT is the difference between the water level in the channel and the total head loss through the launders:

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