Assessment of Peak Water Usage among Residential Consumers across Several Drinking Water Service Areas

Abstract

Public drinking water service providers must comprehensively understand and effectively characterise user demands, especially during peak hours, which not only impact the maximum demand within the distribution network but also determine the dimensions of interior networks within buildings. Residential consumers show different consumption patterns based on socioeconomic factors, spatial location, climatic conditions and the consistency and quality of service delivered by public service providers. This study focused on assessing 1,317,584 users distributed across four distinct service areas in Bogotá, Colombia. To achieve this, a stratified random sampling of 1233 residential subscribers was conducted and 320 reference digital Y290 Aquabus micro-meters were installed to characterise the four service areas. The installations were grouped into sets of 320 users until the entire sample of 1233 subscribers was encompassed. The results demonstrated that the rational method provided the most accurate fit for estimating the probable maximum flow rates compared to the values measured and, consequently, is the most suitable method for application within the region of interest. However, whereas the Hunter Unal method displayed a reasonable fit, it tended to underestimate the size of internal networks within buildings. The remaining methods, such as the British, square root, simultaneity, Hunter, NTC 1500 Hunter and Chilean methods, did not yield significant adjustments and tended to overestimate the probable maximum flow rates as well as the internal networks within buildings. The results indicate that, depending on the method used to calculate the probable maximum flow or design flow of the internal network, there can be a deviation factor when compared to the actual peak flow measured (real maximum flow). This deviation factor ranges from 0.79 (calculated less than measured) to 3.77 (calculated greater than measured). Additionally, a sizing case study was conducted, which involved applying all methods to a scenario involving a residential user. This study aimed to determine the variation expected in the estimation of the diameter of the supply pipe to the internal network when using the flow results from different methods. This analysis serves to conclude the research.