Under the “Grenelle II” law, French water utilities are required to minimise losses in their distribution networks. Under the same regulations, suppliers whose loss rate exceeds a certain threshold are required to draw up dedicated loss reduction action plans. The aim of the aforementioned regulations is mainly to limit the amount of water removed from the natural environment. However, reducing losses within a network does not always mean that water resources are saved. A certain proportion of water lost through leaking pipes and other malfunctions will naturally find its way back into the water table. With this in mind, the French government and ONEMA (French national water body) asked IRSTEA (French research center) to carry out a study into water loss reduction strategies. In water-related legislation, environmental issues are addressed only in terms of the quantitative status of water bodies, whereas in reality, work carried out to conserve water resources can have environmental effects of its own, such as increased use of energy and greenhouse gas emissions. To create the most environmentally-friendly loss reduction strategy possible, these additional effects need to be properly identified. To this end, we carried out a multi-criteria analysis of the environmental impacts of loss reduction activities. Using the Life Cycle Analysis (LCA) method, we examined six types of common work carried out as part of a multi-annual loss reduction strategy. These were active leak detection (using acoustic methods), leak repair, reporting network interventions, estimation of unmetered consumption, pressure reduction, and sectorisation. Proportions for each action were estimated for a network of around 160 km of pipes with approximately 4,000 subscribers. We decided to apply our evaluation to a program of actions, rather than assessing each action individually. This is because loss reduction results from the collective effects of multiple measures. The environmental impacts examined using the LCA method result mainly from work being carried out on water networks. While such work is essential in order to repair leaks and replace defective pipe sections, doing so in an environmentally friendly way calls for a precise identification of defects. Utilities need to have up-to-date knowledge about the state and layout of their network, as well as using the correct tools to identify defective pipes. An effective pressure management strategy can also help to delay the occurrence of leaks. One challenge we face in this study is to assess how much water is likely to be saved by implementing a given action plan. These savings are difficult to estimate because they depend heavily on the characteristics of the network in question (initial performance, knowledge of the network, layout and environment). The next step will be to compare the environmental impacts of contrasted scenarios (LCA Mid Point category). A scenario represents the level of loss reduction that could be expected if a given action plan were to be implemented. Based on the results of this work, it should be possible to identify a level of network performance (context dependent) above which it is no longer environmentally beneficial to continue trying to reduce water losses.