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research. This research stems from work done by various members of the university’s
academic community since 2007 (especially the research group
Ciencia e Ingeniería del
Agua y el Ambiente
from the same university), within the framework of the PUJB’s
Environmental Management Plan. This article presents the procedures followed and the
relevant data necessary for planning and designing the constructed-wetland/reservoir-tank
RWH system. Likewise, select results of data obtained from the implemented monitoring
system are discussed. This case study can be used to disseminate a deeper understanding of
RWH and its impacts on watershed hydrology.
The PUJB’s RWH experience was the product of a series of projects that includes the
assessment of the amount of potentially usable water, the quality of runoff and potential
water uses, among others. These projects were the fruit of a collaborative effort by the
university’s Physical Resources Office (PRO), university researchers, an expert designer
and a construction company.
The first project was related with the assessment of the economic and technical feasibilities
of RWH as an alternative for some uses. Three main aspects were developed in this project:
(i) assessment of the available rainwater volumes and the possible collection points; (ii)
preliminary quality analysis of the collected rainwater; (iii) assessment of the construction
costs for the basic infrastructure required to collect rainwater and of the monetary savings
obtained with the proposed solution (Lara-Borrero
et al.
, 2007).
Subsequently, a project was conducted to know the quality of the stormwater on the
campus and to identify potential water uses. Measurement campaigns were carried out in
March, June, September and October 2009; February, April, August, September and
October 2010; May and October 2011; October 2012. Ten sample points were chosen
according to two criteria: (i) water quantity and quality and (ii) location and proximity to
potential rainwater collection centers. The results of the raw stormwater analysis were
compared with limits set out by FAO (Food and Agriculture Organization of the United
Nations) (Pescod, 1992), EPA (US-EPA, 2004), and standards from Colombia (Ministerio
de Salud, 1984) and Japan (MLIT, 2005). The standards are for non-potable uses: landscape
irrigation, environmental and recreational uses. For each sample point, the runoff water
quality for three storm events was assessed through 25 analytical tests used to quantify
physical properties and chemical constituents.
Later it was carried out another project to assess the inventory of water uses on the campus.
This was done by means of a field study of the campus, using a site record form and the
historical monthly mean drinking water consumption on campus (2003-2010) (Torres et al.,
2011).
Subsequently, a MCDA (Multi Criteria Decision Analysis) tool (called CRIDE:
multiCRIteria DEcision support tool) for supporting the process of decision making for
RWH in PUJB campus was developed. Six scenarios were proposed for RWH and eight
criteria were suggested in order to evaluate each scenario. These scenarios emerged from an
ideal scenario were all the water harvested in the campus would be used (maximum
supply’s volume) with drinking water quality (maximum quality water). The other
scenarios were created by decreasing the water quality (less possible uses) and/or the
