About water pressure
Pressure is the force that pushes water through pipes and it affects the flow from your tap.
The amount of pressure in your home can depend on:
- the height above your home of the service reservoir or water tower providing your supply. Properties at the top of a hill may receive lower pressure than those at the bottom
- how close you live to one of our pumps.
Pressure can also vary at various times of the day – mornings and early evenings are when there is often more demand, and this can cause low pressure.
Inside your home the water pressure can be affected by your plumbing such as:
- the width or texture of a pipe
- a pump/regulator or pump/regulator setting
- the level of water in an attic water tank.
Water flow refers to the amount of water coming out of a tap in a certain amount of time.
This can range from a trickle to a gush.
Water flow depends on the size of your water supply pipe, but it can also be affected by changing a showerhead or tap.
- Older properties: These usually have water pipes that are 15mm to 20mm in diameter. It means the flow through these pipes may only be enough to run one tap. You may experience low flow if there are several taps or appliances being used at the same time.
- Modern houses and flats: These usually have 25mm diameter water supply pipes which can give a higher flow rate – these pipes are more suitable for today’s appliances.
We are legally bound to provide all customers with a minimum pressure of 10 metres head, and a flow rate of at least nine litres per minute at the boundary of your property. This should be ideal for day-to-day use. This should be powerful enough to fill a one-gallon (4.5 litre) container within 30 seconds.
If there are several taps or appliances running at the same time, there may not be enough water for them all and the flow will be low.