Local authorities and their partners must provide detailed specifications for their drinking water supply system and their waste water management system.
This is no easy task for local authorities, as they face the following key problems:
NETWORK KNOWLEDGE
Specifications are expected to include:
The specifications must be compiled and updated every year, indicating any work carried out on the network and data collected during the year.
NETWORK PERFORMANCE
As well as providing these inventories, local authorities are required to ensure that the pipelines are kept in good condition. According to environmental laws, if the network’s yield falls below a certain threshold, the public services responsible for water distribution must implement an action plan before the end of the following term.
NETWORK MAINTENANCE PLANNING
In particular, the action plan involves an annual follow-up check regarding network yield and, where applicable, a programme to implement a series of network improvements over several years.
In accordance with the action plan, the detailed specification for the drinking water supply network should be kept up-to-date, identifying the sections that have been subject to water loss inspections and any subsequent repairs carried out.
DRINKING WATER SUPPLY SYSTEM FIGURES
which means all the pipelines will be replaced after : 170 years
The above figures highlight the need to maintain and renew the water pipeline network in France, both for economic and environmental reasons. Furthermore, the longer it takes to make this investment, the higher the eventual cost is likely to be for future generations.
Based on the inventory, a more ambitious renewal project must be put in place – one that corresponds with the lifespan of the networks. According to industry observers, the average national rate of renewal should be more along the line of 1.25% per year.
WATER NETWORK RENEWAL AS PART OF A SUSTAINABLE DEVELOPMENT PROGRAMME
Recent French legislation has set in motion a move towards sustainable management of the pipe network estate. The required inventory includes elements that are essential for determining a hierarchy of investment for network repairs and renewals.
It only takes a few numbers to understand the reality of the situation and the urgent need to invest in the rehabilitation of the water networks. Of the 906,000 km of drinking water supply pipes, 50% date back to before 1972. The four pipe materials – steel, galvanised iron, PVC and asbestos cement – are the cause of breakages and leaks, and account for around 60% of the estate that needs replacing. Leaks may equally have been caused by damage to the land where the pipes are located, for example sinking or vibrations.
According to the latest Water and Sanitation survey by the Department of Ecology, the network extension is progressing at a rate of 3,750 km per year, whereas network renewals were only 5,041 km per year. At the current rate of investment, it will take nearly two centuries to replace the pipelines. This means that a drinking water supply pipeline will not be replaced for 170 years (906,000 km per year divided by 5,041km), although its estimated lifespan is just 50 to 60 years, depending on the type of pipe. The average renewal rate is therefore 0.6% per year. Economies achieved by reducing water leaks could allow for the renewal of an additional 1,500 to 6,000 km of network.