Water demand is a non-deterministic variable; current normative deliver different flow rates than might occur. Adaptations have been developed in different countries mainly for Hunter's method. The Hydro-Sanitary Standard 'Norma Hidrosanitaria Ecuatoriana' (NHE) 2011 in Ecuador proposes a demand calculation through a modification to the Norme Francaise NF P 40–202. This study proposes an adaptation to the Hunter’s Method using a binomial probability function, based on the disaggregation of time series of pressure and flow, during 62 consumption days, in different water meters, in academic facilities in Loja, Ecuador. Flow curves were developed based on consumption units, which gave very assertive values in relation to the maximum recorded flow rates. Also, in order to approach different estimation methods and since water consumption over time follows a Poisson distribution, synthetic series were generated using the Neyman Scott Rectangular Pulse Model (NSRPM), as this is the one that most adheres to the actual user behavior. Maximum flow rate was also determined with Water Demand Calculator (WDC) and NHE 2011 for comparison with NSRP and research results. Current research is an exploratory approach, has a methodological value for subsequent studies. Proposed Hunter's Method adaptation can provide an accurate flow estimation. Flows obtained with NHE 2011 method were closed to observed only in small facilities. NSRPM method showed an exactness high level, with only a 1.1% percentage difference compared to the measured one.