The North Wales Water Authority's distribution system is a gravity system. This means that the Authority pumps water from individual sources into the NWWA water distribution system to maintain adequate tank levels. The water pressure experienced at any location within our system is solely determined by the elevation of that property relative to the elevation of our water tower.
Since NWWA relies on the force of gravity to deliver water to our customers, water pressure in a particular area depends on how far a property is located above or below the level of the water in the storage tank that serves that area. The farther a property is below the water level in the tank, the higher the water pressure will be at that location.
It is important to remember that vertical distance, or elevation, determines water pressure; physical distance from a storage tank does not. This is why customers with properties in low-lying areas experience higher water pressure than customers located on the hilltops and ridges in our service territory.
A pressure-reducing valve may be required by local plumbing codes in those areas where distribution system pressure is high.
Most low-pressure problems are created in the customer's plumbing system. In such cases, the building has adequate water service pressure, but pressure at fixtures drops off dramatically when another fixture is turned on. Usually the problem is that the water volume is lowered or restricted, therefore reducing the amount of water that comes out of the fixture. Here are some common causes of low water volume. You may have a combination of these problems.
1. Internal plumbing pipes are too small
NWWA water arrives at your business through a service line which can provide adequate volume and pressure. But in many businesses internal piping is down-sized which reduces the volume of water up to 75%, and unfortunately, can cut the pressure up to 75% as well.
2. Small pipes and a long way to go
In addition to downsized piping, the problem is worse when water has to go up more floors or travel long distances. If you're planning to remodel or expand your facilities, be sure to have the water pipe diameter increased to an adequate size.
Long runs of smaller piping reduce the volume of water that can pass through piping, regardless of supply pressure. This is the most common cause of reduced pressure problems.
3. Devices that can affect the volume
Devices such as water softeners, water filters and flow restricting fixtures can further restrict the volume of water flow.
4. Pipe "arteries" are getting clogged
Rust and minerals can build up in older cast iron and galvanized plumbing and restrict the flow of water.
5. High on a hill
If your business is at a higher elevation, your water pressure may be below average. A plumber can offer tips for increasing the volume of water through the building.
You may have one or a combination of problems. Our best advice is to talk to a reputable plumbing contractor. Use this information as a starting point and discuss each scenario. Usually your plumber can recommend solutions that can enhance your water volume.
Water pressure: the force of water pushing on a unit area, usually measured in pounds per square inch (psi).
Static water pressure: water pressure, measured in psi, at the service line when there isn't any water running.
Residual water pressure: water pressure at the service line when water is flowing.
Water volume: the amount of water that a pipe can supply. A 1/2" pipe can only deliver a certain amount of water per minute regardless of water pressure.
