Evaluation of statistical sampling for the assessment of residential consumption totals in water distribution networks

The paper provides insights into stratified sampling, a standard statistical technique that may beemployed to assess domestic water use in water distribution networks. The basic idea is to use onlyfew meters to provide inference on the total water consumption of a network or of a district meteredarea through the knowledge of some additional stratification variables such as household typology,size and occupants number. Since any sampling procedure assumes that the variance of the variableat stake is known, either a suitable amount of past consumption data is necessary, or a specificpreliminary survey must be carried out, in order to define the sampling plan. An application with realconsumption data from a small municipality in Sicily (Italy) shows that number of occupants for eachhousehold is sufficient to design an effective sampling plan and that the methodology can besuccessfully applied in the technical practice, thus allowing to dramatically reduce the number ofcustomer meters to be read in order to quantify total water consumption compared to standardpractice based on the reading of all meters.