Water Leakages in Public Water Supply System and How to Prevent Them

The article addresses the results of effective water losses prevention in public water supply systems, focusing on procedures for monitoring hidden leaks as the main part of losses and as the first step to control and prevent them. The described methodology has been applied based on a cross-border cooperation between twin capital cities Vienna and Bratislava in the Central Europe Region within the project deWaloP （Developing Water Loss Prevention） and adopted in Bratislava Water Company （BVS） in the Slovak Republic. The paper provides a complex of simple and easily available practices for analyses of water distribution measurements bringing essential information as to the necessity to use advanced procedures to actively reduce leakage. These practices involve minimum night flows analyses, hydrodynamic pressures analyses, pinpointing of water leakages by working with valves in the water network, the methodology of setting alarm limits for measured data, as well as use of advanced practices to obtain missing topologic data. As the water infrastructure in former socialistic countries are in bad technical condition and the lack of pertinent operational data is a significant obstacle to the application of a more sophisticated methodology based on GIS and other information systems, the procedures focus on using the most simple way to evaluate and control water losses. Finally, the introduction of described methodology in Bratislava Water Company after many years of unsuccessful effort even with expensive sophisticated leakage equipment brought positive outputs and the graph line of water losses level is finally going down. The use of expensive multi-correlating equipment together with human resources on the basis of implementing the above described leakage monitoring will subsequently become more effective, as it shall pinpoint major leakages, disclosure and removal of that shall significantly contribute to the effective reduction of water losses.

Empowering Conditions for Good Water Governance-a Sustainable Model： Vilanculos Case Study （Mozambique）

This article shows the results of the project Empowering conditions for good water governance-a sustainable model： Vilanculos case study （Mozambique）, co-financed by the European Community. This project had the aim of improving sanitary conditions and increasing economic and financial sustainability of water services for the population of Vilanculos. The project has been developed and deployed with cooperation between Acque del Chiampo （an Italian water utility, near Vicenza）, the University of Brescia and the Vilanculos public water service utility, Empresa Mo^ambicana de Agua （EMA）. The paper reports analytical praxis for water distribution measurements, capable of providing essential data about the water network performances, to assess the eventual need for actions in order to solve possible and effective problems of the water service. These practices involve flow and pressure analyses, pinpointing of the network＇s criticalities and leakages by in-situ inspections along the network, managing the valves together with water service utility, as well as the use of a water distribution model to simulate the effects of the proposed interventions and specific software to automatically register bills and payments.