Leaks in drinking water systems waste around 1 billion m3 of water per year. About 20 % of all processed water that has been added to the system is lost in this way. Public drinking water services use around 50 % of all water resources and must therefore take responsibility for managing its use, as required by the national climate change adaptation plan issued in July 2011.
France has chosen to focus on the reduction of leaks in water systems, subject to relevant regional management, to encourage local communities distributing water to limit this wastage. These communities will now have to provide detailed descriptions of their systems and implement action plans to reduce water wastage within drinking water distribution systems (if their leak rate is higher than the level defined by the decree of January 27, 2012).
From diagnosis to action
The guide, Reducing leaks in drinking water distribution systems - Indicators and methods to define, fulfill and evaluate leak prevention policies in drinking water systems, written by Onema and Irstea (with support from ASTEE) is the result of collaboration between various water stakeholders (operators, communities, design consultancies, research institutes etc.). It aims to help local communities define targeted and effective strategies to prevent water loss.
The guide defines 4 main stages in the process:
- Pre-diagnosis of the situation: detailed description of the transport and distribution facilities for drinking water, evaluation of output and regulatory thresholds, implementation of pre-diagnostic indicators.
- Urgent actions and acquiring a minimum level of knowledge: looking for leaks, checking system linearity, compiling system knowledge.
- Diagnosis: updating system plans, collecting data, updating regional assets, implementing segmentation.
- Designing multi-year action plans: prioritizing, scheduling and evaluating the plans.
The 38 practical pages describe the various tools available to local communities for each stage of this process according to 4 key themes: improving knowledge of the system and of water loss, actively searching for and fixing leaks, managing pressure and replacing and renewing systems.
Four Irstea engineers  worked on writing the guide. The Water Infrastructure Asset Management (GPIE) team at the Irstea Bordeaux center is conducting research in water system engineering: modeling flows, water losses and the effects of aging on infrastructure. The project involves multidisciplinary research, combining water system engineering, applied mathematics, hydraulics, statistics, information and economics and complemented by management science research carried out in Strasbourg  and in the Montpellier center .
For more information
- News. Cleaner drinking water networks !
- Consult the website of the Water Management, People and Uses (G-EAU) joint research unit
- Irstea centers in Bordeaux and Montpellier
 Eddy Renaud, Julie Pillot, Aline Auckenthaler and Claire Aubrun.
 Territorial Management of Water and the Environment (GESTE) joint research unit.
 Water Management, People and Uses (G-EAU) joint research unit.