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First results and future work on a constructed-wetland/reservoir-tank system used
for rainwater harvesting in a university campus in Bogotá, Colombia
S. L. Galarza, J.A. Lara, A. Torres
Research Group Ciencia e Ingeniería del Agua y el Ambiente, Facultad de Ingeniería,
Pontificia Universidad Javeriana, Carrera 7 No. 40 – 62, Bogotá, Colombia.
Keywords: Rainwater Harvesting, Constructed Wetlands, Reservoir tank, SUDS.
Recently, increased attention has been paid to rainwater harvesting (RWH) as an alternative
source of water (Hatt et al., 2006) for uses that do not require potability: landscape
irrigation, toilet discharge, washing floors or building facades (Shuster et al., 2013; Ghimire
et al., 2012). The implementation of RWH techniques in urban areas is considered a multi-
beneficial strategy that provides urban flooding control (Fletcher et al., 2008; Van Roon,
2007) and reduces the need to use potable water for non-potable uses (Wong, 2006). It can
also help relieve pressure on urban drainage systems during strong rain events (EEA,
2012), which reduces and/or solves current water shortages and the pollution of urban
natural waterways (Fletcher et al., 2008; Van Roon, 2007). RWH is additionally recognized
as one of the specific adaptation strategies that the water sector should implement to deal
with climate change (Boelee et al., 2012). It is worth mentioning here that this technique
enjoys more public acceptance than wastewater recycling / reuse / seawater desalinisation
(Brown and Davies, 2007). Although many studies have yielded positive results, there
remains a general avoidance to adopt this technique on a wider scale primarily attributable
to the lack of information regarding RWH effectiveness (Imteaz et al., 2011).
This technique has been successfully implemented as an alternative source of water in some
countries (Lariyah et al., 2011). However, its implementation depends on answering the
following questions (Mitchell et al., 2008): “How much stormwater can be harvested?”
“How reliable is this supply source?” (Farreny et al., 2011), and “How large a storage is
required?” In recent years, studies have shown that rainwater collection and storage
systems employing sustainable urban water drainage –Water Sensitive Urban Design
(WSUD)– generate opportunities for both RWH and grey water reuse (Wong, 2006). The
Sustainable Urban Drainage Systems (SUDS) are included within the WSUD concept.
Initially, these systems were designed for flood control: collecting, storing, and treating
stormwater. They have also been designed to lessen the effects of urban infrastructure (such
as soil impermeabilization and increased water demand) and anthropic activity on water
quality (Berndtsson et al., 2006).
While some research has been done on RWH (Torres et al., 2011a; Castañeda, 2010;
Ramírez, 2009; Lara-Borrero et al., 2007; Ballén et al., 2006; Sánchez & Caicedo, 2003)
and SUDS (Torres et al., 2012; Devia et al., 2012; Álvarez & Celedón, 2012; Torres et al.,
2011b; Gómez et al., 2010; Galarza & Garzón, 2005) in Colombia, no research projects
take into account SUDS for RWH purposes. Hence, the Pontificia Universidad Javeriana
Bogotá’s (PUJB) RWH project seeks to fill the previously mention gap in Colombian
