Outfall, Outlet

Outfall, Outlet

This is the outlet or terminal point to a drainage system that can connect to some open water body, such as a river or lake, or with a pipe or open channel.

The tailwater level here may control flows and water levels upstream through backwater effects.

Outfall nodes are nodes to which flows drain through a DRAINS network. They can be an outfall with a nominated tailwater level, or simply a place outside the system to which flows are directed.

If a user needs to have a tailwater level that varies with time, this can be done using an artificial channel at the outlet. The method is described in a worksheet of the DRAINS Utility spreadsheet.

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