Somehow, terminations need to be built for these systems, like meters. The static pressure will not calculate in a domestic water system, and something like an "Automatic Transfer Switch" has 2 power sources. You might be able to add a connector (on the incoming side) and set up the connector similar to the existing one, so long as it doesn't affect the total building loads. I'm not too keen on this part of revit yet, let us know if you find something.
You will have to create another surface for the connector (the connectors automatically snap to the center point of the surface they are placed on). I forgot that there isn't in out-going connector on that stuff, it is set up similar to a panel. Just add a new Electrical Connector and make the settings the same as the original (the original would be the incoming power service, from the generator or other). add a connector description to help you know what you are connecting to.