How to add sewer data (Water Overlay)

This article is a stub.

For some use cases, it may be important to include sewer functionality in the calculation. Sewers form additional storage for water, and can either store this water indefinitely, slowly remove the water from the hydrological model, or let the water flow in a controlled fashion back onto the surface. Sewers are most relevant for non-sudden excessive water scenarios, such as heavy rainfall.

For the purpose of this use case, a simple hydrological model will be assumed. We will also assume there is an appropriate amount of water present in or added to the model for the sewer to function in a relevant capacity.