Today I'm working on a stormwater network in ArcGIS. I've georeferenced a copy of the Works As Executed plan under the land parcel layer. Then using the plan as a spatial reference, I created the points (storm water pits), and the lines (storm water pipes) as different feature classes, and snap them together to form a drainage network.
After the network is complete, I fill in the attributes and label the points and lines differently, highlighting their unique asset key.
In most drainage networks water flows from a high place to a low reservior or channel. In urban areas this is a constant challenge to deal with overland flow as hard surfaces allow water to drain quicker and pool in low lying areas. Sometimes if a storm water drains and detention basins overflow, then flash flooding can occur on road reserves.
Inter-allotment drainage networks are the responsibility of private land owners, whilst any water that drains out to the road reserve and parkland becomes the Local Council's responsibility.
Knowing how the system works makes it much easier to compile the data into a geographic information system. It was daunting last year as I had literally no idea what I'm doing with the data provided.