Low pressure

Low water pressure

If you have no water or low pressure in your home, this checklist may help you to fix or identify the problem.

1. Search planned or emergency work

We may be working in your area which could affect your water supply temporarily. If it’s planned work, we will let you know by letter 48 hours in advance. 

Check work in your area

If we're not working in your area, it may be an issue with your internal plumbing.

2. Test your stop tap

If you have low flow, check the condition of your internal stop tap. In most cases you’ll find the stop tap under your kitchen sink. To test whether the stop tap is fully open, turn it off (clockwise) and then back on (anti-clockwise) – repeat a few times.

3. Check your isolation valves

These may have been adjusted to reduce high pressure.

Isolation valve 

4. Look for a leak

A leak could affect your water pressure or flow. Find out how to check for a leak.

5. Try your cold water kitchen tap

If this is working fine but you have low pressure or no water elsewhere in your home, the problem is likely to be your internal plumbing. There are a range of ways to improve water pressure in your home – we suggest you contact your plumber. To find one, visit WaterSafe. 

If your plumber thinks you have a low pressure problem, please call us.

About water pressure

Water pressure is the force that pushes water through pipes and determines the flow from your tap. The amount of pressure in your home can depend on:

  • the height of the service reservoir or water tower providing your supply above your home. Properties at the top of a hill may receive lower pressure than those at the bottom
  • how much water other customers are using
  • how close you live to one of our pumps.

Pressure can also vary at different times of the day – mornings and early evenings are when there is usually more demand on the water supply and this can result in low pressure.

The water pressure inside your property can also be affected by plumbing work such as:

  • changing the width or texture of a pipe
  • using a different pump/regulator, or pump/regulator setting
  • increasing or decreasing the level of water in an attic water tank.

Understanding water flow

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. It can also be affected by changing a showerhead or taps.

Older properties: These usually have water pipes that are 15mm to 20 mm 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 pressure powerful enough to fill a 4.5 litre container within 30 seconds. That’s a minimum pressure of 10 metres head and a flow rate of at least nine litres per minute at the boundary of your property, which should be ideal for day-to-day use.

How we can help

Call us if you or your plumber have concerns about low pressure in your home:

0345 600 4 600

(Monday to Friday, 8am to 6pm; emergencies only at other times).

We will check if work in your area is the cause of low pressure. If not, we’ll arrange a visit to test the pressure at your kitchen cold tap.

We will keep you informed about the checks we are doing, explain why they are needed and provide you with written confirmation of the test results.