Rob,
In ISU the following PM objects are used:
- Connection Object (functional location)
--Device Location (functional location)
--- Device (equipment)
So as an example (though there are load of different ways of doing this):
- 10 Flower Street
-- Flat 1
--- Gas Meter
-- Flat 2
--- Gas Meter
---Electric Meter
I suspect though, that you are wanting to map the water system e.g. pipes, valves, meters, etc???
PeteA