Who to ask for network information in my organization?

As a utility, you could ask for network information to:

Hydraulic modeling team: ask them for an EPANET hydraulic model. They may use InfoWater, WaterCAD, WaterGEMS, EPANET or another hydraulic modeling software.
GIS or asset management team: they will be able to give you more insights about the available network information - whether hydraulic model or GIS dataset.
Consultants or contractors you worked with: a hydraulic model may have been created for you by a consultant as part of your water master plan, and they should be able to provide a copy for you.

information sources network contacts network data missing data