Water and Drainage
Water Supply Information
Water Off and Pressure Reduction Notices
Water Supply – Sources
Approximately 98% of water distributed in Dún Laoghaire Rathdown County Council is supplied from Dublin City Council treatment works at Roundwood (Vartry), Ballymore Eustace (Liffey) and Ballyboden (Dodder).
The remaining 2% is supplied from a number of small treatment plants within the County.
The current overall daily consumption in the Dún Laoghaire Rathdown county area is 51 mega litres (11 million gallons).
See Supply Areas and Sources for an indication of the source of water in your area.
See Dublin’s Water at the ENFO site for a history of water supplies in Dublin.
Water Supply – Safety and Wholesomeness
How safe and wholesome is the drinking water in my tap?
Do I need a water filter?
Is bottled water more wholesome than tap water?
Is there a hazard from lead in my water supply?
We are increasingly concerned at the safety of our food and, in recent years, a perception has arisen that the public water supply is suspect. Is this true?
Sanitary Authorities, including Dún Laoghaire Rathdown County Council, are required to ensure that all water supplied in a public drinking water supply meets with strict standards.
Water samples must be taken regularly throughout the water distribution network and tested for a wide range of parameters in accordance with EU regulations [Council Directives 98/83/EC and 2000/60/EC of the European Parliament as effected by European Communities (Drinking Water) (No. 2) Regulations, 2007 - S.I. No. 278 of 2007].
Testing is carried out at Dublin City Council’s Central Laboratory which is accredited by the National Accreditation Board to undertake and certify these tests.
Water supplied in this county routinely achieves a compliance in excess of 99% and is among the highest quality in the country.
Results of water quality testing are submitted annually to the Environmental Protection Agency who summarise them in their annual publication Provision & Quality of Drinking Water - 2007/2008 
(pdf - 1.94MB)
Monthly results of compliance for the main parameters for each water service area are available here: Latest Drinking Water Test Results.
There are no lead watermains in the Dublin area. However, houses built before 1970 may have lead piping from the public watermains to the house.
See Lead in Water Supply for further information.
The strict regime of testing and reporting ensures that the water at your tap is wholesome to drink. If you have a particular reason to believe your water may not be wholesome, please contact the Council’s Water Section for attention.
Water Supply – Taste and Sediment
While the wholesomeness of the drinking water is assured, the more subjective qualities of taste and appearance can be an issue.
In some parts of the network, there can be a taste or smell of chlorine at times.
The actual concentration of chlorine is never remotely high enough to cause health concerns and the taste can be eliminated by allowing the water to stand for a while e.g. by keeping a jug of water in the fridge.
On rare occasions, the water may contain some sediment or appear cloudy.
This is usually caused by work on the network raising sediment in the pipes or entraining air.
Unfortunately it is impossible to avoid this, especially in older parts of the network.
Neither effect is harmful to health and the water normally clears quickly.
Water Supply – Leakage
Is it true that nearly half the water in the network is lost in leakage?
It used to be. However, in 1998 the Dublin Regional Water Conservation Project undertook the major task of tackling leakage in the thousands of kilometres of watermains in the Dublin area. A dedicated leakage team continually audits water flow and leakage in Dún Laoghaire Rathdown County Council is now at around 22%. This is amongst the lowest in the country, despite having one of the oldest supply networks.
Water Supply – Hardness
Other than a small area around Glencullen, the water supplied throughout the county is soft and is unlikely to require further softening for dishwashers or other normal uses. Typical hardness values are as follows:
| Details | Water Hardness |
|---|---|
| Clarke or English Degrees | 3.5 degrees equating to 50ppm Calcium Carb |
| German Degrees | 2.8 |
| French | 5 |
| American | 50 |
Water Supply – Storage
From time to time water supplies must be interrupted, either for planned maintenance or because of a burst in a watermain.
It is our normal practice to advise customers of planned interruptions but it is wise to be prepared for unplanned interruptions; watermains can burst for a number of reasons including ground heave or ground diggers.
Most supply failures will be remedied within 24 hours, so a minimum of 24 hours usage is a prudent amount of storage to provide, see table below for recommended storage quantity.
Very occasionally, it will take more than 24 hours to restore supplies, so consider the economics of providing additional storage if this is a concern. A lost days business might be a high price to pay for skimping on water storage.
| Building or Use | Minimum Cold Water Storage for New Developments Using Low Flush & Dual Flush WC's |
|---|---|
| Dwelling House or Apartment (up to 3 Bedrooms without Power Shower | 227 litres / 50 gal |
| Dwelling House or Apartment (4 Bedrooms or single Power Shower) | 317 litres / 70 gal |
| Dwelling House or Apartment (having 2 full bathrooms) | 682 litres / 151 gal |
| Additional Water Storage per shower en-suite in the above | 90 litres / 20 gal |
| Factory (Staff Use) | 45 litres per each head of staff |
| Offices and Shops | 45 litres per head |
| Restaurants and Canteens | 7 litres per meal |
Burst Pipes
If a pipe bursts in a private residence this is a matter for the householder.
In this instance they would require a plumber.
The Council does not provide a service for effecting repairs on private property.
The Housing Maintenance Department effects repairs to burst pipes in rented Council accommodation.
Air Locks
For advice on Air Locks and how to remove them, please click on the following link Air Locks
( pdf - 100kb)
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