Monday, March 20, 2017

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How Domestic Meters Help To Reduce Leakage

In his fourth article on the work of the Irish Oireachtas (Parliamentary) Committee on Water Joe Dalton takes a closer look at the usefulness of domestic meters as a water loss tool.
Having worked in several countries across the World with domestic water meters, for me it is like entering into a parallel universe when I listen to the fuss they have created back home in Ireland, both North and South. It’s amazing to think that the threat of domestic water meter installations across Northern Ireland by the British Government in 2006 is what finally forced hitherto sworn enemies, Sinn Féin and the Democratic Unionist Party (DUP) into agreeing to split power, allowing them both to block this decision. Domestic water meters – bringing Irish Republicans and Unionists together, who would have thought it back in 1969?

District Meters are a vital tool in water loss management. But the notion that District Meters are more effective than domestic meters at detecting customer side leakages, an idea that has gained traction among some in Ireland, is so at odds with reality I feel I have to spell out this point in detail.

So firstly, and with apologies for the detail, let’s assume that all 4,417 District Meters installed across the state are fully operational and provide full network and customer coverage. Then, as indicated by Jerry Grant from Irish Water, assume there are an average of 1,500 connections per District Metered Area. This will vary, with rural areas in particular having a much lower connection density.

The 4,417 District Meters will provide the very valuable information of how much water is supplied to each area. Dependent on the level of customer metering in each District Metered Area, water loss calculations will be carried out and each area will be ranked in order of priority. Where customers are not metered, usage allowances are made based on the typical usage patterns collected from similar property types where domestic meters have been installed. Based on this ranking, leak detection teams are deployed. The teams will have to survey the main side network and potentially each of the 1,500 customer connections. As they have been deployed to a prioritised area they would expect to be productive with regard to detecting leaks, including customer side leaks.

The advantages of having domestic metering is firstly, uncertainty with regard to the water loss calculations is reduced. Secondly, customer side leaks can be detected rapidly with negligible field work, including in District Metered Areas with relatively low leakage overall. Irish Water reported that 28,000 customer side leaks have thus far been repaired resulting in a water saving of 77 million litres a day, thanks to the data collected from domestic meters. Large numbers of repairs are still pending.

While the software tools available to water utilities are becoming increasingly sophisticated, the notion that these 28,000 leaks would have all been detected as quickly basely solely on District Metering is absurd.

The vast majority of leakage is not visible at the surface. When a leak occurs, time elapses before water engineers become aware of it. Then it has to be pinpointed, and finally it has to be repaired.

Leaks have been known to run for years without detection until ground subsidence finally uncovers it. Trying to minimise the leak cycle time is fundamental to what water engineers do. Domestic meters are of immense help to this. That is not to say that there has to be universal metering where this is impractical to achieve. But the notion that domestic meters are not helpful in reducing leakage is simply not true.

Active leakage control using District Metering should happen regardless of domestic metering levels, and indeed is happening and is of course crucial for detecting main side leaks. But the notion that we must choose between District and domestic metering is a fallacy. They are both immensely useful.

All the fashionable water conservation devices currently being touted by anti-water charges campaigners, such as rainwater harvesting, water butts, low flush toilets etc. make little economic sense compared to a domestic meter. The amount of water saved from these devices is dwarfed compared to the continuous discharge of a long running leak. Even a small leak left running continuously can waste a vast quantity of water over a relatively short time. Indeed, there would be little point in installing all these water conservation devices unless we are going to measure their effectiveness with a domestic meter. This would be a clear example of choosing what sounds trendy over what is the most practical and useful.

The advantages of domestic metering as a leak detection tool were clearly expressed to the Oireachtas Committee by the Group Water Scheme representatives. They were backed up by the Pubic Water Forum’s Mindy O’Brien when citing a leak detected on her own property which she would not otherwise have found. This was along with the evidence from Irish Water.

The best and most cost-effective time to install a domestic meter is when the property is first constructed. The failure to insist on domestic meters on all new-builds during the housing construction boom of the so called “Celtic Tiger”, with the cost of installation borne by the developers, was an act of appalling negligence by Irish Governments of the time.

To paraphrase Oscar Wilde “once is unfortunate, twice is careless”. I would go further and say that if having heard the evidence referenced above our politicians fail to insist on domestic meters for all new-builds, for reasons of short term political expediency, it would be an act of unforgivable self-harm.


James Quigley said...

"District Meters are a vital tool in water loss management. But the notion that District Meters are more effective than domestic meters at detecting customer side leakages, an idea that has gained traction among some in Ireland, is so at odds with reality I feel I have to spell out this point in detail."

Who said that?
Your perception of reality is somewhat skewed. Is this a case of misrepresentation?

Metering is designed to turn water into a commodity and us into 'customers' nothing more nothing less. If it was a case of leakage then talk about the 50% plus of all treated water is wasted on the network side.

Joe Dalton said...


I am not for a second suggesting to neglect water losses on the main side. I’m just highlighting that domestic meters are one of a number of tools available.

I don’t think I have misrepresented anyone. In the Committee proceedings, and in public statements, anti-water charges activists downplay the usefulness of domestic meters as a leakage tool, claiming District Meters are sufficient for this purpose.

Do I take it from your comment that you acknowledge that domestic meters are useful for detecting customer side leakage? Does the fact that they are also used as a charging mechanism mean that their use as a leakage tool is to be abandoned?