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. Typical DMA Meter Fingal has: • 111 DMA’s County wide • 3 New DMA’s will be created every year for the next 5 years 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 - 64.36 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 Glen Ellen, Swords Before : Reduction After : Pressure Management •Pressure - 52m •Pressure - 35m •Flow - 43.5m3/hr •Flow – 25.8m3/hr •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 19th Sept. – 3rd Oct 2006 16 No. Leaks repaired between 22nd Sept. – 17th Oct 2006 Compare flows into DMA before leaks detected (5th – 8th Sept.) v’s after leaks repaired (12th – 15th Dec.) Saving of approx. 25 m3/hr at 4am = 500 m3/day = daily usage for 1,100 houses. Leaks Found Nov 07 – Oct 08 Nov 07 17 Dec 07 12 Jan 08 32 Feb 08 108 Mar 08 40 Apr 08 57 May 08 36 Jun 08 27 Jul 08 12 Aug 08 15 Sept 08 19 Oct 08 20 Total = 395 Leaks Found by Type Leak on Main 12 (3.0%) Leak on Fitting (hydrant, stopcock,valve, etc.) Leak on Meter Box 141 (35.6%) Leak on Communication Pipe Private side leaks 160 (40.4%) 24 (6.1%) 59 (14.9%) Fingal UFW 2008 38% 32% 30% 2008 2007 2006 28% 26% 24% 22% 20% Jl y Au g Se pt O ct N ov D ec 18% Ja n Fe b M ar Ap r M ay Ju n Percentage 36% 34% Month 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.