I'm currently working on a storm network and there's an existing network which I should connect my new network on it.The client gives me all the data I need to build this existing network in shapefile format.
My Question here, should I insert and build the existing network then design my new network? or I can just build my network and define the connection point with the existing network as an outfall? (since the client didn't ask me to analyze the existing network and give me the permission to connect my network on it )
Yes you can. But seeing as the Client has already provided you with shapefiles to create the existing network the hydraulics in this network when your network is connected to it might be worth looking into. You can create the existing network using ModelBuilder. However, it is worth knowing if the existing system is downstream of your network, then the hydraulics would be affected; but if the existing system is upstream, then you have to observe the flow vs time curve at the outfall and specify the same at the upstream manhole as your source.
Also on the other hand if you wish to only design your part of this "combined" network (existing + new) then you can make the existing network inactive and only design the active network i.e. the network you are building.
Hope this helps.
Bentley Technical Support