COMHAIRLE CONTAE ÁTHA CLIATH THEAS
SOUTH DUBLIN COUNTY COUNCIL
MEETING OF ENVIRONMENT SPC
Monday, January 25, 2010
HEADED ITEM NO.
HEADED ITEM: E. Services
5. Water Conservation - Discussion Initiatives
REPLY:
The Dublin region, consisting of the four 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. These four plants are at Ballymore Eustace, Leixlip, Ballyboden and Roundwood.
Three of these plants are operated by Dublin City Council, and one, Leixlip, by Fingal County Council.
The combined maximum output of these plants is 540-550 million litres(Ml) per day. Under normal circumstances, the average demand in the region is 530-540 million litres per day. So, on an average day, the region would have 2-4 per cent spare capacity.
This means the region has to operate its’ plants at 96 per cent capacity, or more, almost every day of the year.
Compare this to Paris, where water is supplied by three major treatment plants, each operating at about 50 per cent capacity.
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).
However, the region will still need further extra capacity to cater for situations like this – and to cater for a long hot summer, if we ever get one.
Dublin City Council is in the early stages of planning a new major water source for the region, but the earliest this would be operational is five to 10 years’ time, due to the procurement hurdles it will have to cross.
No matter how much rain falls and finds its way into the lakes and rivers, these water-treatment plants have a maximum capacity. Like any food factory, they can only produce a certain amount of product every day, no matter how much raw material is available.
In the days leading up to the weekend of January 9th-10th, demand on the system increased to about 570 million litres per day. Over that weekend, demand continued to rise, hitting a record 628 million litres per day on the Sunday the 10th. Demand outstripped production from the 2nd of January until the 15th of January with the shortfall initially being taken out of storage at the reservoirs and then by restricting supplies to the public.
This was due to a combination of extra leaks in the pipe network (caused by frost heave), and the fact that some people left their taps running in an effort to prevent frozen pipes.
This resulted in very low levels at the treated-water reservoirs, with demand far outstripping capacity.
As a consequence, we were left with no option but to restrict supplies to allow reservoirs to recover.
This restriction will have to continue until (a) we recover water in the treated-water reservoirs; and (b) find and fix enough leaks to bring the demand down to the “normal” level.
As the thaw has now come, we expect that people will not feel the need to run taps any more, so this element of demand should correct itself.
Fixing leaks is not a problem for South Dublin County Council or the other councils. However, contrary to popular belief, finding the leaks is the major problem.
Many leaks occur and flow away for days, weeks and even months without announcing their presence, ie where water is not showing above ground. Those that do are quickly spotted and fixed, usually within 24 hours.
Finding the backlog of leaks may take up to four months. However, we expect to have found and fixed enough of them to stabilise the situation and restore normal supplies to the region within a few week.
South Dublin County Council has made every effort to keep their customers informed of the currant situation with regular updates on their webpage at www.southdublin,ie with the times of all cut backs to supplies and the location of all burst that cause localised interruption of supplies.
Water Conservation Advice - Water Usage Figures
Water Conservation Advice - Tap Tips
Water Conservation Advice - SDCC Awareness Campaigns