Automatic water meter reading (AMR) is now the best kind of technology to supply real time information on water consumption. Complete equipment of a district metered area enables the assessment of the total consumption of a finite size population, for a time scale sometimes as short as an hour. However, its cost for generalization can generate high capital expenditures (CAPEX), unaffordable for the utility, in which case sampling techniques have to be set up. With the purpose of total consumption estimation, this article describes standard methods of survey techniques applied to water networks and proposes a methodology for implementation of an operational sample. The methodology, which includes some constraints on the estimator precision, proposes a smart AMR equipment plan of the population, while reducing CAPEX. Finally, estimation of the total consumption, in addition to the knowledge of supplied volume, enables more accurate loss assessment and potential detection of new leaks.