Check your local water quality

DWQR Mapping Application

This application enables you to see water quality data from your local area.

Why do I need the map?

The quality of drinking water varies across Scotland depending on the source from which it is taken. The area supplied by Scottish Water is divided into water supply zones. In order to obtain the data for your area it is necessary to identify in which supply zone your property is located. If you click on where you live on the map, the map will select the data for your supply zone. In some areas, water supply zones may change from one end of a street to the other, so it may be necessary to zoom into a detailed map to select the correct zone.

How do I use the system?

You can locate your water supply zone in a number of ways. You can click on a location on the map, using the controls to zoom in. Once you have found your location, click on it and the relevant supply zone will be highlighted in red with the appropriate data displayed in a set of three tabs. You can type your postcode into the box above the map to zoom straight into your location, then click on it to highlight the supply zone. Alternatively, if you know what the supply zone is called, enter the first few letters and select it from the drop down list.

Supply zones can have complicated shapes, so if you find the system is working slowly it may help to reduce the size of the browser window. Performance should improve the more you use the system. In some locations, notably central Edinburgh and Glasgow, the supply zones are very complex and the system initially plots an approximation of the shape on the map, resolving it with time. If you find the point you are interested in does not appear to be covered by a yellow-shaded supply zone area and is coloured grey, click on each of the supply zones around it and you should find they resolve further to cover your area. If you find your location does not appear to be covered by a supply zone at all, are you sure you don't have a private water supply?

What does the data show?

Scottish Water undertake over 160,000 tests on samples taken in supply zones every year. This is in order to demonstrate that the water Scottish Water are supplying complies with the Regulations. These Regulations set a “Prescribed Concentration or Value (PCV)” or standard for a wide range of substances or parameters that may be present in the water in tiny quantities. Further information on the parameters and their significance may be found here: Ten Key Parameters. It is recommended that you read this section as it will help you to understand what the data means.

Where are these samples taken from?

The data is from samples taken from consumers’ taps at randomly selected properties throughout each zone at a frequency that varies according to the population of the supply zone. The results are taken as being representative of the water quality across the zone, however in practice certain parameters may vary significantly within a supply zone. Plumbing within the property can also affect the results, especially where lead, copper and nickel are concerned.

My supply zone has had a failure – should I worry?

The Quality of Drinking Water in Scotland is very high, but from time to time samples do fail the regulatory standard. These standards are set with a wide margin of safety, and some are concerned with the appearance or taste of the water. All failures must be investigated by Scottish Water and remedial action taken where necessary. Every failure and the associated investigation is reported to DWQR, who will also investigate where this is appropriate. Each failure is also reported to Environmental Health Officers at local authorities and Health Professionals who will take a judgement as to whether the failure has implications for public health and require action to be taken to protect consumers if necessary.

The vast majority of failures that occur are relatively minor and should not be taken as an indication that your water supply is unsafe to drink.

What else should I know about the data?

Smaller water supply zones may have relatively few samples taken for each parameter every year. When a failure does occur in these zones it can appear worse than a single failure in a larger zone where a single sample represents a smaller proportion of the total. The same effect can be seen in the year to date data where a small number of samples have been taken early in the year.

Samples do take time to analyse and report. Scottish Water are required to send all sample data for a particular month to DWQR within two months of the last sample being taken, and DWQR will aim to publish the data as soon as possible after it is received.

If anything in the data gives you cause for concern please contact us using the webform and we will try to assist you.