Читать книгу The Issues and Challenges of Reducing Non-Revenue Water - Rudolf Frauendorfer - Страница 6

Facing ever-increasing urban populations and expanding service areas, many water utilities in Asia and the Pacific continue to struggle with providing clean drinking water to their consumers. Common water supply problems in Asian cities are related to the sources and use of raw water, intermittent supply, and the quality of tap water at the consumer’s end.

One of the major challenges facing water utilities is the large proportion of water loss in distribution networks

One of the major challenges facing water utilities is the high level of water loss in distribution networks. If a large proportion of water that is supplied is lost, meeting consumer demands is much more difficult. Since this water yields no revenue, heavy losses also make it harder to keep water tariffs at a reasonable and affordable level. This situation is common in many Asian cities. “Non-Revenue Water” (NRW)—defined as the difference between the amount of water put into the distribution system and the amount of water billed to consumers—averages 35% in the region’s cities and can reach much higher levels.

NRW is a good indicator for water utility performance; high levels of NRW typically indicate a poorly managed water utility. In addition, published NRW data are often problematic, suspicious, inaccurate, or provide only partial information. Some utilities invent “creative” definitions of NRW, use wrong or misleading performance indicators, and fail to quote important information, such as average pressure and supply time.

Conversely, successful utilities actively address NRW by controlling physical losses, ensuring customer meter accuracy and making all efforts to keep the number of illegal connections within limits. Taking these measures can boost revenue by increasing the amount of water that can be billed while reducing wastage of the product. This increases profitability and improves the return on investment. With larger profits, the utility can then reinvest retained earnings and improve its productivity.

While the benefits of reducing NRW are well known, decades of effort have not delivered much improvement in the developing world. While there are many explanations and excuses, much of the failure is due to underestimating the technical difficulties and complexity of NRW management, along with the potential benefits of taking action.

As long as utility owners are not sufficiently aware they are “sitting on a goldmine,” they will continually fail to incentivize or oblige their chief executive officers to take action (for example, by paying or withholding subsidies). On the other hand, if utility leaders are not sufficiently informed about the level, causes and cost of NRW, along with the potential for improvement, they will not be able to convince their owners to provide funding for NRW management activities and investments. Further, lack of support for comprehensive NRW management by utility owners and chief executive officers makes it difficult to motivate utility staff and provide them with the means (funding, training, and technology) to successfully and sustainably reduce NRW.

As a consequence, billions of cubic meters of treated water will continue to be lost, and water utilities will continue to lose a substantial amount of revenues. To meet growing demand, new resources will be developed, more water will be pumped into the leaking networks, and the vicious cycle will continue.

Physical losses are the main problem

The need for NRW management in general, and in Asia in particular, is so obvious that it is hard to understand why efforts to improve the situation have been so limited. There are, however, a few successful examples of utilities reducing NRW to below 20% (e.g., Singapore, Phnom Penh, Manila [East Zone]) and some places where serious actions have at least started. However, the vast majority of water utilities in Asia are not engaging in serious and professional NRW management.

Expanding water networks without addressing water losses will only lead to a cycle of waste and inefficiency

For many cities, reducing NRW should be the first option to pursue when addressing low service coverage levels and increased demand for piped water supply. Expanding water networks without addressing water losses will only lead to a cycle of waste and inefficiency. Also, a high rate of NRW is closely related to poor energy efficiency, since water transported in networks is “loaded” with energy through the distribution and treatment processes. Thus, energy is lost along with the water. Therefore, reducing NRW is important to overall efficiency and financial sustainability, since it provides additional revenues and reduces costs.

Figure 1Non-Revenue Water Levels of Asian Cities

Notes:

1.Data of most utilities are unaudited and may be misleading.

2.Only some of the utilities have continuous supply—in all other cases NRW would be significantly higher when the system in its current condition would be supplied on a continuous basis.

3.The figures for Phnom Penh and Singapore are unaccounted-for water (UFW). All others are NRW.

4.2009 data are estimated.

Source: Asian Development Bank and Institute of Water Policy, Lee Kuan Yew School of Public Policy. (2010). Every drop counts: Learning from good practices in eight Asian cities. Mandaluyong City, Philippines: ADB and IWP-LKYSP.

In its urban water supply projects, ADB pursues NRW reduction as a key strategy along with increasing production capacity and expanding networks. It acknowledges that reducing NRW cannot be solved through a single project. Long-term engagement and dialogue with governments and water companies are required, as institutional changes take time and pipe replacements alone will not suffice. Rather, NRW reduction requires further effort to maintain low levels once initial progress is made. While ADB promotes utilities to consider private sector involvement (e.g., through performance-based contracts), this needs to be assessed on a case-by-case basis. Along the way, it is important that utilities develop in-house capacity to deal with this core issue.

The main objective of this discussion paper is to provide the basis for a substantive dialogue on NRW between key decision makers at the municipal level, including local government officials, management of water utilities, civil society, and other stakeholders. It aims to raise awareness on key issues surrounding NRW, including the magnitude of the NRW problem in Asian cities, reasons why NRW management is often not practiced, international terminologies and methodologies for improving NRW management, and the importance of using appropriate performance indicators.