A GHG Metric Methodology to Assess Onsite Buildings Non-Potable Water System for Outdoor Landscape Use

Abstract

This paper documents a water:energy greenhouse gas (GHG) metric methodology for a decentralized non-potable water system that was developed as part of a Professional Doctorate in Engineering (DEng) research project by the first author. The project identified the need to investigate the challenges in changing the use of potable water to recycled water for landscape irrigation (LI) and for water features (WFs) at a medical facility case study (MFCS) in Abu Dhabi (AD) (the capital city of the United Arab Emirates (UAE). The drivers for the research project were based on the need for AD to decrease desalinated potable water as well as reduce the environmental impact and operational costs associated with the processing and use of desalinated water. Thus, the aim of the research discussed and presented in this paper was to measure the impact of using recycled and onsite non-potable water sources at the MFCS to alleviate the use of desalinated potable water and reduce associated energy consumption, operational costs, and GHG emissions (latterly in terms of carbon dioxide equivalent (CO 2e ), for LI and WFs. The analysis of three case scenarios at the MFCS compared different approaches to alleviate energy use, costs, and GHG impacts for the use of recycled water in LI and WFs against a baseline. The findings led to a proposed sustainable water conservation and reuse (SWC) strategy, which helped save 50% desalinated potable water for LI use by soil improvement, building water system audits, and alternate non-potable water reuse. The recommendations for this paper are to develop a SWC strategy forming the basis for a water protocol by the competent authority for regional medical facilities including an assessment methodology for building decentralized non-potable water systems to measure their energy, GHG emissions and financial impact.

Water resource management in the context of a non-potable water reuse case study in arid climate

“…In the USA, in 2002, water consumption ranged from 260 to 1128 m 3 per year per patient bed for hospitals in the 133-510 bed range (Healthcare Environmental Resource Center (HERC) 2015), which represents 0.71 to 2.21 m 3 per day per bed, respectively. Yet hospitals' water use varies widely depending on type, size, geographical location and water use equipment and practices (Seguela et al 2020). The MFCS records indicated 2.97 m 3 water consumption per patient bed per day (see Fig.…”

Non-potable Water Quality Assessment Methodology for Water Conservation in Arid Climates

“…Due to peak condensate formation occurring in summer, there is a short fall availability in winter, which is proposed to be met firstly by soil amendment [8,9], secondly by alternative non-potable water reuse and thirdly by building system audit. This is to reduce the use of potable water for outdoor use, to assess nonpotable water effect on plant growth, and to reduce building systems water and energy consumption, operation and maintenance cost and practices, and ultimately greenhouse gas emissions [10].…”

“…WATER BALANCE [6,28,51,52] SOIL:WATER STRATEGY [6,28] REUSE OF ADDITIONAL NON POTABLE WATER SOURCES [6,52] BUILDING WATER SYSTEM AUDIT [6,51] PROPOSED SUSTAINABLE WATER CONSERVATION AND REUSE (SWC) STRATEGY Non-potable water Quality Fig. 10 Summary of the water conservation protocol for a decentralized system adapted from [10] c Test the selected non-potable water generated on-site for SARw, EC, toxicity, and microbiology (the latter specifically for healthcare). d Classify the non-potable water type selected under either ultra-electrolyte water, process/industrial, or greywater type.…”

Evaluation of a Landscape Irrigation Management Strategy to Support Abu Dhabi Update Its Water-Related Standards

“…Due to peak CW formation occurring in summer, there is a shortfall in winter (established at −19,235 cubic meters per year (m 3 /year) in 2016). Water and soil data were used to develop sustainable water consumption and reuse (SWC) strategy forming the basis of a water conservation protocol [3] whereby soil improvement for the landscape is investigated as part of a mixed methods approach [4][5][6]. This strategy would enable the MFCS to address the five-month CW shortfall, reduce the outdoor use of desalinated water, and, consequently, would reduce the MFCS's building systems water and energy consumption, operation and maintenance cost and practices, and ultimately greenhouse gas (GHG) emissions.…”