WSDP: MODULE 3 TOPIC 8: WATER CONSERVATION AND WATER DEMAND MANAGEMENT STRATEGY 8. WATER CONSERVATION AND WATER DEMAND MANAGEMENT STRATEGY 8.1. WATER RESOURCE MANAGEMENT INTERVENTIONS CoCT is committed to implement the previously proposed and approved WCWDM Strategy (2007) and the newly developed WCWDM Strategy once finalised, in order to reduce the water losses within the distribution systems as follows: Description GOAL A 2011/12 Target 15.3% >15% Apparent Losses (Unbilled Unauthorised Consumption) Unauthorised Consumption 7% 6.3% 4% 1.0% 1% 1% 6.0% 5.0% 3%-4% Real Losses Leakage on Transmission and Distribution Mains 12.8% 12.71% 9.3% 9.18 8%-9% 8%-9% Leakage on Overflows at Storage Tanks 0.05% 0.10 - Leakage on Service Connections up to point of customer meter Negligible Negligible - 23.4% 20.5% >20% Water Losses GOAL D 2010/11 (Baseline) 19.8% Customer Meter Inaccuracies NRW Intervention - Meter replacement program -Meter Audits and data clean-up Conforms to International benchmarks. Water Audits would be useful in reduce and maintaining - Water Audits - Meter age analysis/Audits Meter replacement Program -Pressure Management -Leak Detection -Pipe Replacement Monitor and respond to concerns – pro-active maintenance and on demand maintenance/repairs. - Unbilled Authorised Consumption 3.61% 5.15% 2%-3% Apparent Losses (Unbilled Unauthorised Consumption) Real Losses 7% 6% 3- 4% Metering and monitoring and pro-active maintenance SAP clean up As stated in Goal A 12.8% 9.3% 8-10% As stated in Goal A 3.52 The target for 10 year Water Conservation and Water Demand Management Strategy is less than or equal to 15% by 2015/16 according to director objectives. 8.1.1. Reduction of Wastage The overall target of this goal is to reduce water wastage by consumers. A number of projects have been implemented involving promotional projects (awareness and educational campaigns); regulation and enforcement; development and implementation of equitable tariff structures; customer assistance towards efficient water usage (retro-fit programmes) and targeting inefficient use within CCT operations. 8.1.2. Water resource management interventions: Situation Assessment and Implementation progress to date The annually average water produced in 2011/12 stood at 330.04 Mm3 per year. On average, the volume of water produced has always been greater than water supplied. Nevertheless, water production steadily decreased from 336.64 Mm3 per year in 2010/11 to 330.04 Mm3 per year in 2011/12. The Water Demand Management Unit has initiated many projects with the intention of reducing the water demand. In addition, most of the maintenance activities of the Reticulation branch also have a Water Conservation/Water Demand Management impact, for example replacing a leaking water main. 8.1.3. Targets for reducing unaccounted for water and water inefficiencies Unaccounted-for water (UAW or water losses) for the period July 2011 to June 2012 stood at 15.3%. The target for 10 year Water Conservation and Water Demand Management Strategy is less than or equal to 15% by 2015/16 according to director objective (see Table 2). 3.53 8.1.4. Reducing high-pressures for residential consumers: urban Pressure reduction (Installation of smart pressure reducing valves as well as advanced pressure management). Reducing pressure in the network has an immediate effect on the leakage in the system and also aids in enhancing the life of the pipe-work infrastructure. Lower pressure reduces usage with every opening tap action in a pressure managed network which is an immediate saving. It has the added benefit of reducing the amount of apparent losses that occur as a result of meter inaccuracies. The latter is due to a smaller volume of water flowing through the meter. Overall pressure reduction reduces the overall strain and stresses on the overall system. 8.1.5. Reducing high pressures for residential consumers: rural The City has a very small rural component and reducing pressures here will result in an insignificant water saving. 8.1.6. Public information and education programmes Consumers have been made aware of the need to save water through a variety of means. Many shopping malls have been targeted in the Metro together with the Airwave media. Display stands have been set up at most events held around the City including during Local Government-, Water- and Sanitation Weeks. Education institutions and schools have also been targeted for education programmes 8.1.7. Leaks Projects The focus here was to fix leaks in domestic plumbing on private property. The following projects have been undertaken to date: Fixing of leaking infrastructure (taps, toilets, cisterns) on low-income household properties Installation of Water Management Devices to assist consumers to manage their water consumptions Plumbing in low cost housing were leaks can be least afforded remains a concern, there is a need to work close with the housing department to explore ways to improve the pluming specification, inspections and construction supervision of pluming in low cost housing. 8.1.8. Leak and meter repair programme: rural See urban. 3.54 8.1.9. Working for water programme; Removal of Alien Vegetation The CCT has an ongoing programme for the removal of alien vegetation in the catchment areas of their dams. This programme will have the effect of increasing available run-off. The CCT also contributes towards the removal of alien vegetation in DWA catchments through a catchment management charge. The City’s Integrated Aquatic Weed Control Programme aims to assist with management of alien aquatic weeds which occur in rivers, canals, wetlands, dams and treatment ponds. Depending on conditions prevailing in the target water body, mechanical, manual, chemical or biocontrol methods may be recommended. 8.1.10. Treated Effluent Re-use Two thirds of the City’s water consumption ends up in the 27 Wastewater Treatment Works and from there the final effluent is discharged back into the environment. The opportunity for re-using the treated effluent has not yet been fully exploited. Thus far, the majority of Golf Courses in the City are using treated effluent for irrigation purposes, as do parks and sport fields. A limited number of Industries are also benefiting from the lower tariff. Currently, approximately 691.51 Ml/month (as at end of June 2012, USPC 2012_06 (08)) of treated effluent is consumed. It is important to note that the volume of treated effluent consumed does not directly translate into water demand savings, as not the full volume of treated effluent use replaces potable water demand. A portion of the use replaces ground water use or in specific cases what otherwise would be no use at all. 3.55 8.1.11. Water resource management interventions: Future trends and goals The WCWDM strategy is looking to further implement various programmes/interventions in order to conserve our water resource and reduce the consumer water demand. As the implementation of the WC/DM Strategy intensifies the assumptions will be tested and the targets reviewed either up or down depending on the accuracy of the current assumptions. District management areas will be implemented throughout the Council by installing additional district meters. Leak detection activities will be intensified and a dedicated team will soon be established. 8.1.12. Public information and education programmes The following programmes/projects will be continued: Aftercare Programmes & liaison Schools training 8.1.13. Leak and meter repair programmes: urban The following initiatives are planned for over the next two years: Further comprehensive demand projects will be identified and rolled out over the next 5 years. In Delft, the integrated leak repair project was implemented and is now complete. The Fix-It leak projects will continue in various areas. The Fix-It leak projects targets high-volume consumers in low cost areas until such a time as a comprehensive demand project is implemented. A comprehensive debt management policy has been implemented. Part of the debt management will be to introduce flow limiters (water demand management devices). The debt management policy will be implemented as part of the comprehensive demand management projects but also on an ad-hock basis for high-volume consumers in low cost areas as part of the Fix-It leak initiative. 8.1.14. Leak and meter repair programmes: rural Refer to 8.1.15 3.56 8.1.15. Funding There are a number of examples in S.A. where large industries have sponsored various WC/WDM initiatives by Councils in order to ensure a more secure supply of water. This idea can be expanded considerably and can be utilised to fund a number of the proposed WC/WDM initiatives. There are also a number of foreign programmes that offer funding opportunities. Some examples are the UN habitat programme and the African Cities Water Conservation programme. There are a number of private companies that are willing to enter into concessions or joint management contracts to manage Water Services delivery or specific key performance indicators such as the reduction of non-revenue demand. 8.2. WATER BALANCE By undertaking a water balance, WSAs can calculate the amount of water that is being lost to their systems. The non-revenue water provides an indicator of how efficiently the water supply system is being run, and provides information to the WSA on how to improve the system. Non-revenue water is a direct loss to the WSA. 3.57 Note: The calculation of the IWA water balance was performed using the best available information at present and in some cases estimation based on input from officials within Water and Sanitation. Therefore the accuracy of the IWA water balance can still be improved. Table 1: Non-Revenue Water balance according IWA balance Billed metered consumption 719.18 Billed Authorised Ml/day Consumption 719.18 719.18 Ml/day Authorised Revenue Water Billed unmetered consumption Ml/day 0 Ml/day Consumption 765.75 Unbilled Metered Consumption Ml/day Unbilled 37.08 Authorised Ml/day Consumption 46.57 Ml/day Unbilled Unmetered Consumption 9.49 Ml/day System Volume Unauthorised Consumption Input 9.04 Apparent Losses 904.22 Ml/day Water 54.56 Ml/day Ml/day Non Revenue Customer Meter Inaccuracies 185.04 45.52 Ml/day Ml/day Water Losses 138.48 Ml/day Leakage on Transmission and (20.5% of Input Distribution Mains Volume) 83.03 (15.3% of Input Volume) Ml/day Real Losses 83.91 Ml/day Leakage on Overflows at Storage Tanks 0.88 Ml/day Leakage on Service Connections up to point of customer meter Negligible 3.58 Table 2: Water Demand Growth Rate Year Percentage Water Demand Growth 07/08 2.29% 08/09 3.21% 09/10 1.65% 10/11 1.66% 11/12 -1.94% Average 1.4% Note: Expressing NRW as a percentage of the system input is not encouraged as it can be misleading as percentage figures are strongly influenced by the consumption. One of the objectives of the strategy was to have a system in place which assesses the overall water balance. There is a need to develop or set a system which will aid in accurately determining and analyses of water losses as per requirements as set out by IWA. It is important to note that currently free basic water is about half that of non-revenue water and close to the value water lost through real losses. 3.59