City of Tshwane Water Conservation and Demand Management

City of Tshwane: Water Conservation and Demand Management Strategy and Activities Presented by Trevor Westman November 2015

OBJECTIVE OF PRESENTATION • Present an overview of the Water Supply Value Chain • Define the major contributors to Non-Revenue Water (NRW) in the City • Key Initiatives • Investigate the challenges inhibiting effective NRW reduction in the City • Define a way forward to deal with reducing NRW and increasing Revenue in the City, taking into account budgetary constraints, latest available technology etc

WATER SUPPLY VALUE CHAIN Water Resources Water Purification (Own Plants, Water Boards) Waste Water Treatment Bulk Distribution Real losses (Leaks, pipe bursts, etc. ) Role Players: Department Water and Sanitation Bulk Storage Water Boards Municipalities Real losses (Leaks, pipe bursts, etc. ) Service Providers Waste Water Collection Reticulation Household/User Water wastage, inefficiencies Customer responsible after meter W Water meter/measuring Municipality responsible up to meter Real losses contributes 80% of total losses (NRW)

Co. T WATER SYSTEM STATISTICS JUNE 2015 Item Size or Quantity System input volume Non-Revenue Water (NRW) Total Losses per pipe length Total Losses per connection Length of Bulk and distribution Mains Storage Reservoirs Storage Towers Control Valves (PRV’s, Flow control etc) Bulk Management Meters Consumer connections 342, 2 million m 3/annum 87, 9 million m 3/annum (25, 7%) 15, 5 litre/min/km 0, 329 litre/min/connection 10 505 km of bulk and distribution mains (excluding pipes downstream of supply point to authorised zones) 165 storage reservoirs with 1 868 Ml storage 38 water towers with 13, 03 Ml storage on 29 sites 442 installations 871 495 695 (formal connections only)

WATER LOSS TERMINOLOGY (DEFINITIONS) • Apparent Losses: This is water which “disappears” through inaccurate metering, inaccurate meter accounting processes, illegal connections etc. The water is not physically lost from the system but it is never measured or accounted for, and, importantly, not paid for. • Real (physical) Losses: This is water which physically disappears from the distribution system through problems such as holes in pipes, reservoir overflows or evaporation. It is thus water which does not reach the customer and is not paid for by customers. If real losses are reduced, more water will be available for distribution to customers at much lower economic and environmental cost than augmentation of supplies. • Non-Revenue Water (NRW). All water supplied which is not billed (Free basic water is considered to be Revenue Water)

MONTHLY NRW • • • Figures depict 12 -month rolling average Increase in NRW evident over last 5 months NRW – 25, 7% (approximately 87, 9 million kl/yr = R 527, 4 mil/yr Not all NRW can be recovered due to unavoidable real losses Average NRW of SA Metros was 35% but latest reports seem to indicate an upward trend

MAJOR CONTRIBUTORS TO WATER LOSS The total loss in the City amounts to 87, 9 million m 3/annum (June 2015). • Apparent losses make up about 20% (17, 6 million m 3/annum, R 105, 6 mil/yr) of the total water losses, and as follows: - Metering 6% - Illegal connections 6% - Data errors 8% (meter reading, billing, data transfers) • Real (physical) losses contribute to approximately 80% (70, 3 million m 3/annum, R 421, 8 mil/yr) of the total water losses

Co. T NRW REDUCTION INITIATIVES The Co. T has a comprehensive 25 point Scorecard (Activities), used structure the Water Conservation/Water Demand Management strategy and to assess the potential for WC/WDM in the Co. T. Key elements of this strategy include the following: Targeting Apparent losses (20% of total water loss) (these initiatives also generally improve revenue): • Large Consumer (Commercial/Industrial) Meter Audits • Meter replacement programmes • Data purification Targeting Real losses (80% of total water loss)(these initiatives also decrease water purchases): • Pressure Management: Reduced pressure results in lower leakages • Smart Pressure Controllers: Time-based controllers are used to reduce pressure without customers being unduly affected • Pipe Replacement Program: Replacement of worn out network pipes • Visual Leak Inspections: Pro-active and low cost activity to identify unreported leaks in reticulation systems • Improve on reaction time of leak repairs • Minimum night-flow logging General • War on Leaks (Social Responsibility - Job Creation and Skills Development) • Network Sensing: Monitoring of pressures and flows to provide early warning when systems fails or when large bursts occur • Zone Investigations: Analysis of zones to study trends and identify problems in water distribution zones

SUMMARY OF WATER CONSERVATION AND WATER DEMAND MANAGEMENT (WC/WDM) STRATEGY

SYSTEMS EMPLOYED: IMQS (Infrastructure Management Query Software)

SYSTEMS EMPLOYED: IMIS (Infrastructure Management Information System)

SYSTEMS EMPLOYED: ZEDNET (Web based data acquisition and display system) Unreported leak in open field on 300 mm dia. pipe resulted in flow increasing by 1000 m 3/hr, real time alerting system resulted in quick leak repair

PRESSURE MANAGEMENT • Lower Pressure = Lower Leakage • Pressure management is one the primary initiatives in high leakage zones with high pressure • Pressure management areas are continuously identified, supported by information regarding the frequency of bursts in the zones and high minimum night flows

PRESSURE MANAGEMENT: SOSHANGUVE TT Reduction of minimum night flow from 90 m 3/hr to 56 m 3/hr after intervention

METER AUDITS IN Co. T INDUSTRIAL AREAS • Audit of all connections in industrial areas (large users) • Locate un-metered connections • Identify and replace all old, broken, illegible meters • Ensure all meters are on billing system • Assess Impact

WATER METERING/MEASUREMENT • • Conventional Metering Water Management Device (WMD) Pre-Payment Advanced Metering The four fundamental drivers for a comprehensive and appropriate metering are equity, water efficiency and the environment, economic benefits and system management. It follows that accurate metering plays a pivotal role in determining the levels of Non. Revenue Water (NRW), which in its turn is interrogated in order to investigate the causes of water loss or inefficiency and thereby propose, implement and manage various interventions to improve or lower the existing levels of NRW. A cost benefit analysis needs to be done to determined the selection of the measurement system of water consumption in the City.

ADVANCED CUSTOMER METERING: CSIR

STATE OF THE WATER NETWORKS • A Pipe Replacement Program was developed to determine the condition and priority of pipes to be replaced within Co. T • Pipe Replacement Potential (PRP) is measured in % for each of the 10, 500 km pipelines • PRP is determined by multiplying the Likelihood of Failure factor with the Consequence of Failure factor. • Factors are determined by: – – – Pipe Diameter; Pressure in the pipe both static and dynamic/Infiltration volume Catalogue remaining useful life Pipe Material in combination with geology Pipe breakages/failures Master Plan item and Master Plan implementation year (when pipe should be upgraded due to capacity issues) • By using the abovementioned program the replacement of water pipes can be prioritized to replace the most critical worn out pipes.

WATER INFRASTRUCTURE PIPE CONDITIONS: COSTING IN TERMS OF REPLACEMENT CLASSIFICATION

CHALLENGE: DECREASED ABILITY TO REPAIR LEAKS ON TIME Response times trends in recent years (The norm is 70% with 48 Hours) Year % Leak Repair in 48 hours 2010 78% 2011 74% 2012 73% 2013 65% 2014 48% 2015 38%

WHERE TO FOCUS? GET THE BASICS RIGHT • The reduction or speedy repair of physical losses should be prioritised since this segment accounts for approximately 80% of the total water losses in the city. Decreased performance in leak repair activities due to constraints such as lack of resources: personnel, budget, vehicles, materials, equipment, tools, wrong routing of complaints (customer care issue) results in unnecessarily high water purchases from service providers. • Replace old and failing water infrastructure timeously: Insufficient capital budget to fund the replacement of old/failing water reticulation networks increases maintenance cost, greater reliance on maintenance staff, increases risk of failure. • Minimise zonal pressure as far as practically possible by installing pressure management systems, supplemented by pressure controllers to further reduce zonal pressure during off-peak consumption periods and at night. • Continuously monitor minimum night flows in the various reticulation systems in order to pinpoint areas of high leakage or problems with zone discreteness. This information is analysed in conjunction with the monthly water balance results for each zone. Savings achieved from focussing on the basics can be used to fund other water loss and revenue generation initiatives.

ACHIEVEMENTS OF THE Co. T REGARDING WATER LOSS REDUCTION • First prize in the Department of Water and Sanitation’s (DWS) National Water Demand Management Sector Awards for Water Demand Management in 2009, second and third prize in 2012 and 2013. The Co. T is the only metro in the RSA that has received an award in every DWS Water Demand Management competition. • The Co. T has one of the lowest percentages NRW of all Metros in the RSA • Co. T have world class water management systems in place

THANK YOU