Frank Austin, Director of Water Services for Dún Laoghaire Rathdown County Council, delivered teh below report to the Council this evening (08/03/2010) on the water supply in the County:
Water Supply in the County
The Dublin region, consisting Dún Loaghaire-Rathdown, the other three Dublin county councils, Kildare, northern Wicklow and a small part of Co Meath, is supplied with drinking-water from one common network. Four main water-treatment plants provide the bulk of drinking water to this network.
The three plants operated by Dublin City Council are the most significant in the DLR context being Roundwood, Ballyboden and Ballymore Eustace. The fourth plant is Leixlip, operated by Fingal County Council.
The combined maximum output of these plants is 540-550 million litres per day. Under normal circumstances, the average demand in the region is 530-540 million litres per day. So, on an average day, there would be 2-4% spare capacity in the system. This means the plants are operated at 96 per cent capacity, or more, almost every day of the year.
The age of the DLR network reflects the heritage of the County with the infrastructure following development in the 19th and 20th century from the coast and the expansion of what were rural villages for example in Stillorgan and Dundrum. Of 1000km of pipework in the County over 40% are over 50 years with many km up to and even over a hundred years old.
Dún Loaghaire-Rathdown is fed from four main reservoirs of treated water:
- Church Road
The Dundrum and Stillorgan electoral area is, by and large, fed from Stillorgan and Sandyford reservoirs. The Dún Loaghaire and Blackrock area from Church Road and Stillorgan and Ballybrack from Rathmicheal, Stillorgan and Church Road. Both Church Road and Sandyford reservoirs are refilled every night by pumping from Stillorgan and Ballyboden respectively. Areas such as Killiney, Stepaside and Foxrock are supplied by means of pumping from the reservoirs. This aspect of the network is due to the topography in the county which is hilly and at many different levels. For example
Foxrock is located above Stillorgan and has a pumped supply while Blackrock is below it and fed by gravity.
The cold spell over late December 2009 and early January 2010 was a 1 in 50 year event in the Dublin region and as a consequence there was a significant disruption to the regions water supply. There were also restrictions in the Council’s independent supply in the uplands.
The pre-Christmas local demand was 59 million litres per day of which approx 29% was leakage on the public and private side. This water is delivered to 196,000 people in 70,000 households. There are approximately 3,500 non domestic customers including businesses, schools, nursing homes and hospitals. In the days leading up to the weekend of January 9th-10th, local demand on the system increased to about 62 million litres per day. Over that weekend, demand continued to rise, hitting a record 72 million litres per day on the Sunday. While this average rise is 25% across the county some of the older supply zones particularly in the east of the County increased by 50%.
Regional demand hit a record of 628 litres per day.
This was caused by a combination of extra leaks in the pipe work (caused by frost heave) and extra customer usage, possibly running taps or private side leakage.
A major emergency was not declared but the structures outlined in the DLR plan were put in place. A crisis management team staffed by senior engineers and communications and customer service staff was mobilised at the start of the crisis to oversee operations and communications and the water services staff on the ground were augmented by staff from other Departments in the Council as the situation moved from crisis to recovery. The crisis team met daily and was also in daily contact with DCC water services and DLR was represented at all regional coordinating meetings in the city. Contact was made with the HSE regionally and locally. Contact was also made with individual hospitals and nursing homes in the County.
DLR took steps across the county to restrict supplies to customers to maintain minimum levels in the treated water reservoirs as did the other Councils in the region. Pressure reductions are an essential mechanism to save water where the leakage has increased significantly since the thaw.
A designated in house call centre supplemented by the after hours service dealt with thousands of calls in January. Calls have now decreased significantly. Our seven day emergency blog updates to customers has proved especially useful in providing advance water off/pressure reduction notices. This information has also been relayed on a daily basis directly to Councillors, TDs and Senators. The media have been kept informed on a daily basis and a number of interviews have been held and broadcast on national/local radio. We have received positive feedback from customers on the blog, in particular, however in recognising that the website is not the only channel to get information out to our customers, some of whom do not have internet access, we have launched a dedicated Aertel page for DLRCC (page 630) for all television users.
The objective is to give at least partial supply to all household’s attic tanks over a 24-hour period. Priority is therefore given to restore water to those who have had interrupted supply for more than 24 hours. Repairs to burst mains are prioritised to assist with achieving the above and to repair the bursts which have the highest losses. Where this is not possible mobilisation of tankers is considered. In the first week of the crisis there were a large number of bursts in the Killiney / Dalkey area and it was necessary to mobilise static tankers. Mobile tankers were used in several other areas of the County and some nursing homes had their tanks supplemented from mobile tankers.
We have now restored minimum levels in the reservoirs although the Sandyford, Church Road and Rathmicheal reservoirs remain vulnerable to interruptions in supply. There has been a general reduction in daytime pressure throughout the County. We have moved from countywide nightly shutdowns to nightly pressure reductions, across the county, from 22.00 to 6.00 on the following day. These reductions are being incrementally relaxed.
DLR contains a high proportion of older housing stock with associated older plumbing systems. Householders living in these older houses are likely to experience delays in the restoration of full water supply and in particular the re-filling of storage tanks.
The restrictions are also impacting on some customers more severely because they may be at the end of the pipe and / or at an elevated level and not necessarily that there are undetected leaks in the vicinity.
These restrictions continued until—
(a) we recovered water in all the treated-water reservoirs in the region; and
(b) find and fix enough leaks to bring the demand down to the “normal” level.
A reduction in the current demand for water can be achieved through a combination of finding and repairing leaks that have developed over the last few weeks. DLR has deployed additional resources to the area of leak detection and repair to support those normally involved in water conservation work. This response has extended throughout the night in many cases and over the weekends since problems began.
The work is focusing on the pipes and networks for which the Council is responsible. Over two hundred leaks have been repaired since the start of the crisis. It is vital too that householders and business owners check to find and repair leaks on the private (consumer) side. It is also important for householders and businesses to play their part and conserve water.
As we located and fixed more leaks we have incrementally reduced the severity of the pressure reductions.
Many leaks occur and flow away for days, weeks and even months without announcing their presence, i.e. where water is showing above ground. Those that do are spotted and we would thank the public for reporting leaks to us (e-mail email@example.com). It’s more difficult to identify the underground leaks, particularly when the water pressure is low. The pressure and flow data from the network is analysed on a daily basis. Teams are then targeted to investigate those areas that are experiencing excessive demand. The finding of the underground leaks is an iterative process that can take some time and is often done at night.
The confirmed leaks are provided to our maintenance teams and assessed on
(1) the impact the loss of water is having on customers (i.e. are households without water as a direct result of the burst?),
(2) the volumes of water being lost, and
(3) whether the loss of water through the burst can be controlled or reduced by other methods before it can be repaired (for example, can the Council isolate that section of watermain pending repair)
Once the burst has been categorised it is then prioritised for repair as soon as possible.
Some locations may require the mains to be shutdown to facilitate repairs, crews are also attending to leaks on service pipes and maintenance work on water fittings which either require no mains shutdowns or minimal mains shutdowns. In the current situation it is not always possible to give advance warning of the repair locations to customers. There are also locations that require traffic management measures to be put in place.
The Council, along all the other local authorities in the region, continues working to restore a normal supply to everyone. Finding the backlog of leaks may take a number of weeks.
The Council are asking the public to conserve water and thanks the people who have made sacrifices to ensure that supply can continue to be available to the community.
Due to the severe shortage of water people are asked to STOP using water for washing driveways, cars, footpaths and non essential uses and also follow the water conservation tips on www.taptips.ie
The measures required in the future are
- To increase the available supply by expansion of the treatment capacity.
- Reduce demand on the system by rehabilitating older parts of the networks and encouraging the public and business to conserve water.
- Provide extra storage reservoirs and links between them to improve the resilience of the system.
There are projects at both the planning and construction stage in the region and the County to address all of the above.
- The demand increases of the past 10 years have largely been met by implementing leakage reduction measures and by expanding the supply capability of existing Dublin Region sources. To address the lack of spare treatment capacity, Dublin City Council is expanding its plant at Ballymore Eustace (which will provide extra water later this year) and Fingal County Council is about to go to tender for an expansion of its plant at Leixlip (which will provide extra water in about two years).
- Projected demand increases from 2010 to 2016 will be met by this further development of the existing water supply sources to their sustainable limits and by further reducing leakage levels through network rehabilitation initiatives in the region. This “knife-edge” approach will continue to be required until a new Major Source for the area can be identified and developed to completion.
- Provision made in the 2007 -2009 Water Services Investment Programme by DEHLG was €118 m for the Dublin Region Watermains Rehabilitation Project (DRWRP). Any individual contract must receive appropriate DEHLG approvals before proceeding so DEHLG determine programme delivery. Between works done by Contract and some direct labour by DLR 6.5 KM costing €2.8M has been rehabilitated to date funded from 2007-2009 Water Services Investment Programme and DLR funds. DEHLG are not in a position to approve any new works pending publication of 2010 -2012 Water Services Investment Programme (due for publication in weeks). We hope that DEHLG can provide funding to continue the good work over the next 3 years.
- The planning phase for rehabilitation works in Sallynoggin 10.5KM, Blackrock 2.5km and Monkstown 9.3KM are nearly complete and it is hoped that these schemes would commence on site within the next year. The works identified in DLR under this project involves the rehabilitation of 60 km ( including the above ) at a budget cost of €20.7M. Under the 2007 -2009 WSIP this was to be funded by DEHLG 90% and DLR 10%.
- The Sandyford High Level Water Supply Scheme is designed to address the water supply deficiencies in the areas surrounding Sandyford, Ballyogan, Carrickmines, Stepaside and Kiltiernan. The existing system is inadequate due to unsatisfactory security of the current supply and its inability to meet future demands. The infrastructure being provided was sized taking into account the water supply requirements of potential future development identified in the 2004-2010 County Development Plan, the Stepaside Area Action Plan, the Glenamuck/ Kiltiernan Draft Local Area Plan and the Sandyford LUTS Study update. The construction contacts for two reservoirs, two pumping stations and 7km of pipeline will be completed in the coming months. Total Scheme cost, incl contract, non-contract and advanced works, is over €20m, of which DEHLG is funding €13m, balance to be paid by DLR
- Other schemes such as the two specific recommendations on water storage at Rathmichael/Cherrywood and Ballyman contained in the Dublin Water Supplies Studies – Storage report deal with infrastructure deficiencies in the southern part of the county, together with the required ancillary infrastructure such as an upgrade of the pumps at Ballyboden and provision of a link from Rathmichael supply area to Church Road supply area. These projects are at the planning stage.
The Council is undertaking a full review of the challenges presented by the recent extreme inclement weather both locally and in conjunction with the Region and will use the outcomes to help us tackle such events in the future.
Director of Water & Waste Services