Foreword
Water Conservation is becoming more and more important in the Council’s function of delivering a safe, secure and reliable water supply to the people of County Limerick.
Increasing demands on limited resources means the benefits of the project are clearly visible. The cost of treating, pumping, storing and delivering water to every home in the County is increasing. Water Conservation also has a major benefit to the environment, less water used, means more water stays in its natural environment.
Background
Limerick County Council’s supply network includes over 1800km of water main of various sizes and materials. The condition and age of this network varies widely also. On average, that network supplies over 55 million litres of drinking water everyday.
It is part of the Limerick County Council’s responsibility to maintain this network and to pinpoint areas for improvement going in the future. Water Supply is dependent on such factors as reservoirs, production facilities, arterial mains, distribution pipes and of course consumers.
The supply of potable water to Limerick County Council’s customers is hindered by the following, poor pressure, poor supply and Unaccounted For Water (UFW) – water lost as a result of bursts and leaks.
Water Conservation Project Timeframe
The Limerick County Water Conservation Project commenced in January 2002. The Project phases are as follows: -
Phase 1 Implementation of Water Management Systems
This includes asset data collection, mapping (GIs), modeling, bulk and district metering, telemetry and pressure control. The collecting of information to enable the computerisation of the entire County water distribution network on to a Geographical Information System (GIS), a full assets register. The project included the provision of full MapNet GIS Records, strategic planning, leak detection, training implementation and record keeping.
Phase 2 Active Leakage Control
This involves the location and repair of leaks. The systems provided at Stage 1 will allow the most problematic areas to be targeted.
Phase 3 – Rehabilitation
The leakage control strategy implemented at Phase 1 and 2 above allows the identification of areas with persistent high leakage, poor response to repair activities and level of service problems. Pipe sampling and testing can validate the condition of such mains. Investment can then be targeted on those sections yielding the best return.
Department of Environment and Local Government
It should be noted that the Limerick County Council Water Conservation Programme is fully supported by the Department of the Environment & Local Government.
“Water conservation is an integral component of the Water Services Investment Programme and is a key to the sustainable use of water resources. Apart from Environmental gains, the delivery of additional water supply through leakage control is a viable economic alternative to capital infrastructure provision. Water conservation also protects capital investment in water supplies and reduces operational costs. The Minister is anxious, therefore, that each local authority should implement and maintain an effective water conservation programme in its area.” Extract from Circular Letter L6/05.
Leak Detection
A major part of the works undertaken by the Water Conservation Project involves the detection of leaks on the network. To this end, Limerick County Council have employed project staff consisting of two leakage crews and a leakage foreman who have become highly skilled in the areas of leakage detection and pressure management. A total of 3524 (Dec 05) leaks have now been identified in the water distribution network since the project commenced in 2002. In 2005, a total of 706 leaks were identified in the network.
Active leakage control and pressure management within the County has resulted in water savings in the region of 3100m3/day (682,000 gals/day) approximately.
Unaccounted For Water (UFW)
UFW is the demand that remains once legitimate assessed non-domestic and domestic use is deducted from the overall demand in the network.
Prior to the implementation of water conservation, programme studies estimated that nationally, almost half the water being produced was Unaccounted For Water (UFW). UFW occurs for example where pipes are leaking, illegal or unknown connections and consumer negligence.
Limerick County Council has targetted UFW in an effort to reduce increase demands on resources. UFW now accounts for approximatly 30% of consumption.
Nightline
The nightline is a term used to describe the water being used in a system at the lowest demand time. This is ussually between the hours of 4am and 6am. It can be assumed that the majority of usage at this time in any given system is leakage. Leak detection uses this nightline in an attempt to target areas for active leakage control.
Economic Level of Leakage
Economic level of leakage can be defined, as that level of leakage at which any further reduction would incur costs in excess of the benefits derived from the savings. In any given system, leak detection can achieve reductions in leakage. However, in successfully reducing leakage there comes a point when the amount of time and cost required to continue to find additional leaks in a system outweighs the benefits of finding the additional leaks.
Location of Leaks and Known Water Wastage
Limerick County Council would ask for help from everyone in locating leaks and known water wastage.
Energy Conservation
As part of the brief of the Water Conservation Project, work has been carried out on the pumping times and pumping durations at Limerick County Council’s water supply plants. Direct savings have been achieved as follows:-
- leakage detection which has reduced the quantity of water pumped and the pumping duration;
- pumping times have been altered to take advantage of night time rates;
- plant equipment has been inspected and billing rates altered to increase efficiency and minimise costs.
Water Conservation is Good for the Environment
Like all natural resources, we don’t have an endless supply of water. The less water we use, the less water we have to treat; meaning more water stays in its natural environment. This website contains tips on Conserving Water in the home or garden. For tips, please see link to Water Conservation Tips.
For help and advice on how to conserve water at home, call Limerick County Council at 061 49 63 26.
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