A procedure to analyze the viability of rainwater harvesting systems in urban areas based on pre-defined diagrams

Abstract

Giving some specific precipitation regimes and technical design parameters, urban Rainwater Harvesting Systems (RWHS) may represent an alternative source to drinking water supply system promoting its conservation and rational use. The use of RWHS requires the definition of generic and simplified method for sizing RWHS accumulation tanks, which is has being considered the most expensive component of the system. Additionally, several methods have being used to define reservoir volumes leading to a wide variety of final reservoir volumes many of them over estimated. The main objective of this article is to present a new methodology to define RWHS reservoir volumes considering technical and economic viabilities of the systems. The proposed methodology was incorporated into a Decision Support System (DSS), named SARA. The method provides an alternative way to define smaller RWHS reservoir volumes once it accepts lower levels of reliabilities giving that the RWHS is considered a complimentary system, better suited for urban areas. RWHS design diagrams are built as a result of the methodology in an attempt to offer a tool to initial and rapid design of reservoir volumes for RWSH. The method was applied to different urban areas in Brazil.

Feasibility, seasonality and reliability of rainwater harvesting in buildings of a university in Campina Grande, Paraíba

“…Many other researchers that have assessed the potential use of rainwater focus on residential buildings as a study area (Chaib et al, 2015;Sampaio & Alves, 2017;Teston et al, 2018;Maykot & Ghisi, 2020). However, it is necessary to extend this knowledge to other kinds of buildings since they are also water consumers and need to have a rationalized demand, especially in regions with a semi-arid climate, where the scarcity of water resources is even more pronounced.…”

Assessment of rainwater harvesting system through continuous simulation with sub-daily data

“…After simulations of the scenarios, the performance evaluation of RWHS in runoff control was done with indicators ER V and ER Qmax (Equations 4 and 5). As to meeting demand, the RWHS was evaluated from two dimensionless indicators defined by Dixon et al (1999), and adopted by Palla et al (2017) and Sampaio & Alves (2017): water saving efficiency (E) (Equation 7) and rainwater overflow ratio (O) (Equation 8).…”

“…where: Y t (m 3 ) represents the rainwater supply (yield) at each time step t, D t (m 3 ) is the rainwater demand at each time step, O t (m 3 ) represents the rainwater exceeding the system capacity at each time step t, Q t (m 3 ) is the system inflow in the reservoir at each time step and N is the total number of simulation time steps. The indicator full reliability (FR) (Sampaio & Alves, 2017), has been also used, as per Equation 9.…”

Socioeconomic potential for rainwater harvesting systems in southern Brazilian municipalities

“…In Brazil, several studies have considered the technical evaluation of rainwater harvesting for specific buildings, normally placed in urban centres (Sampaio & Alves 2017;Geraldi & Ghisi 2018), including households (Ghisi & Oliveira 2007;Ghisi et al 2012;Marinoski et al 2018), industrial companies (Azambuja Teixeira et al 2016;Andrade et al 2017) and educational institutions (Salla et al 2013;Marques et al 2014;Amorim et al 2017;Silva et al 2019;Thomé et al 2019).…”