Help and Contact

Water Quality Guide

Our guide to keeping your water wonderful 

We have created this guide to help you with any queries you may have about the quality of the water coming from your taps. The guide will offer advice on how you can address any issues you may be experiencing and also explain what we will do if your water is anything less than WONDERFUL. 


How we keep your water safe

In the UK we have some of the highest standards of water quality and safety in the world. At Severn Trent we want to make sure all of our customers have the highest level of water quality therefore we clean, disinfect and test your drinking water thoroughly, to make sure it’s safe to use, before it leaves our treatment sites and arrives at your taps. 

Pipes and water quality you are responsible for

Our wonderful water is always on tap and we work hard to make sure it is available for you 24/7. Every day we send our water to you via pipes in the road. The pipe that links the water main in the street to the boundary of your property (often called the communication pipe) belongs to us and is our responsibility to maintain and ensure good quality water flows into your home.

The pipe that leads from the boundary of your property to the point where it enters your home is the homeowner’s responsibility along with all of the internal plumbing.

Checking and looking after your own water quality

There are lots of ways we can help you to look resolve a water quality issues you might experience.

Find out how you can diagnose and fix common problems. 

Top Tips

  • Regularly clean your household taps, including any attached fixtures or fittings, thoroughly using a dilute bleach solution ensuring that you wash inside the spout. Make sure you follow manufacturers cleaning instructions to ensure you don’t damage the tap!
  • After cleaning the tap, run the water for a few moments to remove any remaining disinfectant
  • To prevent possible contamination do not leave items such as flannels and dishcloths on the tap to dry and never allow food or animals to come into contact with taps

Water quality issues you could encounter

We strive to ensure our water quality is of the highest standard for all our customers, however we know sometimes the quality of water can change. Below are a few examples of changes to your water quality and what you should do if you encounter them.

Nothing to worry about!

If you experience any common household water quality issues, don’t worry. These are often simple to fix and you can diagnose and resolve your water quality issue at home yourself. 

If the following water quality issues persist, please contact us online or you can call 0800 783 4444 and someone will be able to support you with your query. Alternatively, you can write to us at Severn Trent, PO Box 407, Darlington, DL1 9WD.

Top Tip

Often running the tap for about 2 minutes can clear any water quality issues – give this a go at home!

Please contact us...

If you experience any of the following water quality issues, you should contact us immediately.

You can get in touch online or by calling us on 0800 783 4444 and someone will be able to support you with your query.  


For more information about these water quality issues please visit My Water Quality

What happens when you contact us about a water quality issue

Step 1 – Contact and guidance

When you contact us, our advisors will ask questions to understand a bit more about the problems you’re facing. We will then go through some simple steps to try and help you clear the issue yourself. You may have already tried this yourself but please bear with us as we want to make sure everything is sorted for you as quickly as possible.

Step 2 – Triage and diagnosis

Once our checks are complete if we find that the water quality issue has arisen due to an appliance in your home e.g. a washing machine or even your hot pipes – this is classed as a private problem and something which will be your responsibility to fix. We will of course talk you through the best way to get this fixed, however should we find that we need to do more investigation then we will take down your details and ask a specialist team to call you back to carry out the diagnosis.

We will call you back as soon as we can however please be aware that this may sometimes take up to 48 hours after your initial contact.

Step 3 – Confirmation of diagnosis

If we have been unable to diagnose the water quality issue on our first conversation, our specialist team will receive details of your initial contact and they will carry out an assessment. Once the assessment is complete they will then call you to discuss their findings.

If you’re not able to answer their call, a voicemail will be left for you and a text message will be sent detailing your assessment results. Remember we’ll only be able to send you this text if we have your mobile phone number, therefore please keep your account details up to date with your latest information.

If you have any questions about the assessment results please contact us and we will aim to have our specialist team on hand to talk you through your results.

We will send you a letter in the post to confirm what we found from our analysis.

Step 4 – Sampling (only if required)

At Severn Trent we pride ourselves on having the very best water quality for our customers. Our specialist team do their very best at diagnosing issues over the phone, however should we not be able to we may be required to carry out a further investigation at your home. We would do this by taking a sample of some of your water. If we feel sampling is required at your home we will contact you to make an appointment.

We do carry out regular spot check sampling throughout the year, however this is randomised and for more information on this please see the random sampling section in this guide

Step 5 – Visiting your property and taking a sample

Should a sampling appointment be made, we will initially agree a day with you and a morning or afternoon slot.

On the day of your appointment the sampling engineer will call you in the morning of the visit and will agree a more specific time period by phone. When they arrive they will take the sample, either from the boundary box, or from your kitchen tap. Where they take the sample depends of the type of testing required. Once the samples are taken, the sampling engineer will give you a leaflet with some water quality guidance and the sampling reference number which you can use when calling for information about your results.

If you weren’t home when the sampling engineer came to take the sample, they will arrange for you to receive a call to re-arrange your appointment.

If you weren’t home but we were able to take the sample, we will post a calling card through the door to provide information on the next steps and provide you with your sampling reference number.

If the sampling engineer notices something different to our usual standard, the sample will be fast tracked to the office.

As a result we may ask you not to drink the water until further investigation has taken place.

We will mark these investigations as highest priority and will aim to resolve as quickly as possible.

Step 6 – Receiving your results

It is important to note that bacteriological sampling results usually come back the next day, but chemical tests can take up to 10 working days. Once we have received the results our specialist team will give you a call. If you’re unable to take our call, we’ll leave a voicemail with the results.

Once all the results are in, we will also send you a letter to confirm the outcome of all the tests completed. Sometimes we need to repeat our testing, or carry out different tests, depending on the results of the initial sampling. If this happens, we will call you to book another appointment.

The types of random sampling we do

In order to continuously supply our customers with high quality water and fulfil our regulatory obligations, we take 21,000 random water samples each year. The results of these samples are then shared with the Drinking Water Inspectorate (DWI) so that we can make sure our water quality is of the highest standard.

Getting results from the random sampling

If we find there is an issue we will inform you and keep you updated. If there are no issues found we won’t automatically let you know however the results are uploaded on to the website every quarter as part of the typical water quality data for your area (which can be accessed by entering your postcode).

Proving our identity when we visit you

If you want to check that the Water Engineer at your door really does work for Severn Trent, you can check their identification card and then call our bogus caller number on 0345 604 1655.

For added peace of mind, you can join our Doorstep Password Scheme to protect you or your household from bogus callers.

How the Priority Services Register can help you and your household

We understand that sometimes you or your family members need long term support. We are able to offer you tailored support by assigning you to our Priority Services Register (PSR). This is a free service and means we can learn a bit more about you and help us understand your specific needs. Our PSR is here to support all, whether you or your family member are facing ill-health, financial worries, language barriers or physical or psychological ill-health. We are here to try and provide some support to you and your family during that period.

Find out how we can help you and your family.

More help and support

Contact us if you have any questions about your water quality

 If you have further questions about the above policy, please contact us  and someone will be able to support you with your query.

Alternatively you can write to us at Severn Trent, PO Box 407, Darlington, DL1 9WD

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