Rapid urbanisation and industrialisation in Vietnam has led to a significant increase in its daily water consumption. In order to meet water demand, the country is aiming to reduce its non-revenue water rate to 15% by 2025.
Vietnam, as well as other developing countries, has a rate of non-revenue water of about 30-40%. Due to rapid urbanisation process, an expansion of the distribution network is compulsory to meet the increasing overall water demand over time. One way to solve this issue is to find a method to reduce non-revenue water and use the saved water to serve customers. This method is economic and friendly to the environment compared to construction of more plants.
Vietnam National Non-Revenue Water Reduction Programme
The National Programme was introduced, among others, to mobilise and gather resources for the activity of preventing non-revenue water. The main mission is to reduce the country’s non-revenue water rate from 30% in 2009 to 15% in 2025. The programme includes the following activities:
- Preparing record of pipe network, water meter, managing network and using water meter by Global Positioning System (GPS) and Geographical Information System (GIS)
- Preparing annual plan for inspection, replacement of pipe route and equipment on the network of water supply pipe
Currently, in Vietnam, many water supply companies have a policy to setup a GIS-based Management System in order to achieve this target.
Major challenges in non-revenue water reduction projects in Vietnam
The data needed to reduce non-revenue water come from many sources with different nature and can be divided into the following main types:
(a) the network, including model and operation information;
(b) customers and consumption volume;
(c) spatial information of the above-mentioned types and various base maps
Normally, this information is available in the water supply companies; however, it may not be standardised, sorted and referenced well in terms of geography to put into database for analysis and statistics.
Besides, due to the nature of not having an integrated database address, the complex relationship of householder and customer, the geographical reference of invoice information (for example) is very difficult. Therefore, this preparation of data is a major challenge in non-revenue water reduction projects in Vietnam.
The combination of GIS’s strength and the information system into the reduction of non-revenue water was used broadly all over the world in order to increase the efficiency of the traditional non-revenue water reduction (Work-Hard) and decrease the Economic Loss Level (ELL). This method is called “WorkSmart” in Denmark.
”WorkSmart” includes activities such as:
(a) optimal management of pressure;
(b) online monitoring of new leakage;
(c) pipe replacement planning;
(d) hydraulic model of network; and
(e) preparing IWA water balance table
The prerequisite condition to implement “WorkSmart” is the good statistics: “You can’t manage what you don’t measure!”
The construction of such a system for a water supply company is a continuous and complex process which can be divided into many phases:
(a) setting the database;
(b) design the network management system;
(c) integrating model system; and
(d) building the supporting system for non-revenue water reduction.
All the above-mentioned information will be managed and analysed by a non-revenue water reduction system in GIS-based receiving update data from SCADA, model, invoice, etc. The system will automatically produce an IWA water balance table for each District Metering Zones (DMZ).
IWA Standard Water Balance Table
Based on the water balance table, strategy of non-revenue water reduction for each DMZ area is made and this strategy can be updated, changed to be suitable with the state of that area over time. Thanks to this procedure, the non-revenue water reduction is implemented more efficiently, quickly and more targeted.
Hot spot area of leakage
Real-time leakage monitoring based on minimum night flow
“WorkSmart” was successfully applied in many places in Denmark which is a country with an average volume of non-revenue water of 6% – the second lowest in the world (European Environment Agency). In Seremban, Malaysia, this method helped to reduce the non-revenue water level from 39% to 24% in 12 months with the investment expenses returnable within 2 years by the saved non-revenue water.
The application of “WorkSmart” allows water supply companies in Vietnam to minimise investment and shorten the duration for non-revenue water reduction project in line with the country’s policy of sustainable and green development.
If the non-revenue water level of each year is reduced by 2 to 2.5%, the commercial water will increase by 25 million m3/ year equivalent to the construction of a new water supply system with capacity of 100,000 m3/ day.