Water Services National Training Group Best Practice in the Management of Drinking Water

Water Conservation Lar Spain Senior Engineer Fingal County Council

Water Conservation - Context Financial – Treatment, Pumping, etc. Leakage Control pays for itself. Service to customer improves. Ecological – Waste of resources, Sustainability. Public Health – WTP’s overstretched

What is Water Conservation/Leakage Control? ??

What is Leakage Control?  Is it this….

What is Leakage Control? Or This….

What is Leakage Control?  Or is it this…

What is Leakage Control?  Active Leakage Control  Leak finds you – Easy.  You find leak – Hard.  70% to 80% of Active Leakage Control is spent gathering and refining data.  DATA IS THE KEY!

Spot the Difference….. Both are Leaks. LHS Service Leak – RHS a 150 mm Burst. LHS “Reported” – RHS “Unreported”.

Active Leakage Control - DMA’s Looking for unreported bursts/leaks in a county is like looking for needles in a field of haystacks. DMA’s - tell you which haystacks (DMA’s) have needles and which don’t. Allows you to target your resources. Subdivide county into District Metered Areas (DMAs) and measure flow into each DMA. Try to have no more than 1,000 properties in each DMA (Urban Areas – Rural dictated by geography).

Benefits of DMA’s Identify unreported bursts and leaks. Reduce leakage runtime. Prioritisation of target areas for leakage inspectors. Can tell you number of Service Leaks and/or Mains Bursts that you have to find. Network performance can be monitored. Data available for design, planning and forecasting.

District Meter Areas District Meter Areas are: Metered Areas feed by a single supply (not always). Designed to accommodate a maximum of 1,000 properties (Domestic and Non Domestic – Urban/Rural differences). Connected to the regional Telemetry Network or logged to enable remote monitoring. Fingal has: 111 DMA’s County wide 3 New DMA’s will be created every year for the next 5 years Typical DMA Meter

Water Audits DMA Inflow - Domestic Demand - Non-Domestic Demand - Customer Losses - Operational Usage Net Distribution Losses (UFW) Leakage is part (most) of UFW

Domestic Demand Has to be estimated – we use 148 l/person/day. The Per Capita Consumption (PCC) Figure can be exceeded (>148 l/person/day) – makes UFW increase (in hot weather for example). Accurate Population Figure also needed.

Non-Domestic Demand Meter error. Meters being bypassed. Unmetered Non-domestics (should be gone). Illegal tappings off mains. Mobile Vehicles eg. Road sweepers/commercial tankers filling from hydrants. Fire Flows.

Losses and Usage Customer Losses l/prop/day (average) Operational Usage – 1.2 l/person/day (fire hydrants, flushing mains, road sweepers etc. by the Local Authority)

Leakage Team - Tasks Tracking house counts/population. Better estimates for PCC. Gathering Meter Readings – question. Metering missed Non-Domestics. Chasing new Non-Domestics. Chasing as-built drawings. Confirming/correcting record drawings.

Leakage Team - Tasks Drop-Testing DMA’s – to check for integrity and/or breaches. Checking Boundary Valves. Drop-Testing Reservoirs. Installation/Retrieval of Loggers. Step Testing. Sounding. Correlating.

Leakage Team - Training Large commitment to Training required. Can take some time to “get up to speed”. Issue when staff changes – particularly Engineer. WSNTG – existing training courses – being updated – ready Spring 2009.

Network Management & UFW Network Management - understanding Network - where water is being used. Identifying Unaccounted-for Water (UFW) - big challenge. Achieved by undertaking a series of analytical steps: Water Audits (Trunk and Distribution Mains). Water Supply Area (WSA) and District Meter Area (DMA) Audits. Commercial Audits. Domestic Usage Audits (Per Capita Consumption).

Locating Leaks Audits confirm a leak as the reason for the UFW. Locate the Leak(s) Step Testing - Breaking a DMA into sections to narrow down where the leak may be. Leak Location – Aural Sounding using listening sticks (Traditional Method) or using electronic acoustic equipment to identify the leak Mains Burst The most important activity in this process is to EXPEDITE the leak repair. Mains Burst when identified should be repaired within 24 hours.

Operational Barriers Operational Barriers (UFW Show Stoppers) Lack of clear as-laid information on new infrastructure constructed by others Quality of Workmanship Standard of Materials used Boundary Breaches – operational changes. Getting repairs done quickly. Recent Example of Qualtiy of Workmanship: In 5 NEW Estates in Balbriggan [2,000 Houses] – 111 Leaks were located. All of these were down to the Quality of Workmanship

Pressure Management Pressure Management: Is a proactive method of protecting vulnerable infrastructure. Extends the asset life of the pipe network. Reduces burst frequency. Also Reduces amount of Leakage. Fingal has: 29 PRV’s County wide 10 Further Locations under consideration Typical Cast Iron Pipe Sample

Pressure Management Glen Ellen, Swords Before : Flow m 3 /hr Pressure - 52m After : Flow – 25.8m 3 /hr Pressure - 35m Reduction Flow – 41% Pressure – 46%

Pressure Management Day/Night Controllers Day/Night Controller on trial in Donabate DMA. Night-time pressures (0:00 to 06:00) reduced from 28m to 20m. Reduced flows by 10m3/hr for this period. Total saving over 6 hrs =60m3 =approx. daily water supply for 130 houses.

Fingal DMA’s

Typical DMA

Fingal’s Leakage Team 1 Leakage Engineer (Exec). 1 Leakage Supervisory Inspector. 4 Leakage Inspectors. 1 General Operative. All DMA meters connected to Regional Telemetry System. Repairs by Maintenance Crews.

Example - Savings Example: River Valley DMA 16 No. Leaks Detected between 19 th Sept. – 3 rd Oct No. Leaks repaired between 22 nd Sept. – 17 th Oct 2006 Compare flows into DMA before leaks detected (5 th – 8 th Sept.) v’s after leaks repaired (12 th – 15 th Dec.) Saving of approx. 25 m 3 /hr at 4am = 500 m 3 /day = daily usage for 1,100 houses.

Leaks Found Nov 07 – Oct 08 Nov 0717 Dec 0712 Jan 0832 Feb Mar 0840 Apr 0857 May 0836 Jun 0827 Jul 0812 Aug 0815 Sept 0819 Oct 0820 Total = 395

Leaks Found by Type Leak on Main12 (3.0%) Leak on Fitting (hydrant, stopcock,valve, etc.) 141 (35.6%) Leak on Meter Box24 (6.1%) Leak on Communication Pipe 160 (40.4%) Private side leaks59 (14.9%)

Summary Active Leakage Control – the only way. Accurate data is the key – continue to refine. Leakage Teams need long-term support. Water Conservation is not a “Project” – it’s never ending. Resources need to be committed for the long term.