The DWS has a potable (drinking water quality) water supply. This supply may come from several possible sources.
- Municipal water supply
- Delivered by truck
- Collected from rainwater
- Water wells
- Process water from creeks, streams, rivers, lakes, etc.
The domestic water system will consist of two basic components:
- The Inlet, Potable Water side, internal distribution system with piping/plumbing/heating
- The Outlet, Waste water side (sewage) collection and removal system.
Domestic water systems have been around since the dawn of time, when the first thinking man located his home 'domicile' next to a running water supply, streams, rivers etc., for an available running water supply of fresh water and send waste water away from his domicile.
The same system that serves as a domestic Water System in residential homes, is also seen in commercial, institutional (hospitals, schools, nursing homes) as well as many other more industrial applications.
The fresh water system side delivers clean, safe, potable water to each service point in the distribution system, DWS. It is imperative that the clean water not be contaminated by the waste water (disposal) side of the process system. The water may require additional processing prior to qualifications as potable water.
The waste water side of a water system, provides a means of receiving, connecting to and removing the waste water from the plumbing system. Sanitary, drainage, check valves, waste and vent systems exist to be physically isolate the waste water from the supply side (potable water); using air gaps, air breaks and backflow preventers, and check valves.
- An isolation valve must exist between the water source (say from the city) and the fixture (sink faucet)
- beyond the isolation valve, it is common for sinks to use flexible hosing from the pipes to the fixture, and more permanent fixtures (showers, toilets, etc) to use rigid piping. It is undetermined whether such flexible hosing is acceptable for in-wall piping, assuming it's located after an isolation valve (say for a shower faucet).
