Potable water use of residential consumers in the Cape Town metropolitan area with access to groundwater as a supplementary household water source

An object based household water cycle model has been developed using Matlab (Simulink) in the WaND (Water Cycle Management for New Developments) project to facilitate the development of an optioneering tool. The aim of the tool is to allow the assessment of options for conventional and innovative water management over the long term. Benefits of this approach include flexibility, easy expansion and transferability. An object is defined as a generic abstraction of micro-components which have similar functionalities in a household water use context. Following this concept, four kinds of objects are employed - water source, water use, treatment and sink. Each object has a generic interface which indicates its main attributes and functionality. Micro-components which belong to the same object share the same generic interface. An object can be easily implemented by specifying the associated property table and Matlab file. This forms a system - objects - micro-components - database hierarchical architecture. This paper describes the model development so far and includes initial model runs to demonstrate the power and performance of the approach.

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Drought response impacts on household water use practices in Cape Town, South Africa

Water Policy ◽

10.2166/wp.2020.169 ◽

2020 ◽

Vol 22 (3) ◽

pp. 483-500 ◽

Cited By ~ 2

Author(s):

Phikolomzi Matikinca ◽

Gina Ziervogel ◽

Johan P. Enqvist

Keyword(s):

Water Use ◽

Water Conservation ◽

Water Demand ◽

Demand Management ◽

Management Strategies ◽

Cape Town ◽

Qualitative Understanding ◽

Household Water ◽

Depth Interviews ◽

Water Use Practices

Abstract Cape Town recently endured a record-breaking drought which nearly ended in disaster for the city's water supply. Municipal authorities introduced several measures to curb water demand using both monetary and other incentives, but little is known about how effective these measures were at encouraging people to save water. Previous literature shows no consensus as to which types of measures are most effective for managing residential water demand. Using information obtained through semi-structured, in-depth interviews with 20 individuals living in houses where they paid their water bills, this study provides insights on how respondents interpreted and responded to these mechanisms. Results show that price mechanisms were considered to be ineffective and did not encourage people to save water in their households. Non-price mechanisms were seen as having more impact on respondents, encouraging water conservation behaviour; especially when it comes to household indoor water use activities related to hygiene. While previous studies primarily provide quantitative data to measure the effectiveness of water demand management strategies, this paper adds a qualitative understanding of how and why households' water use practices change in response to these measures.

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Water use and acute diarrhoeal illness in children in a United States metropolitan area

Epidemiology and Infection ◽

10.1017/s0950268810000828 ◽

2010 ◽

Vol 139 (2) ◽

pp. 295-301 ◽

Cited By ~ 5

Author(s):

M. H. GORELICK ◽

S. L. McLELLAN ◽

D. WAGNER ◽

J. KLEIN

Keyword(s):

Surface Water ◽

Water Use ◽

Metropolitan Area ◽

Water Source ◽

Bottled Water ◽

Well Water ◽

Source Surface ◽

Water Type ◽

Gastrointestinal Complaint ◽

Water Users

SUMMARYWe examined the association between water exposures and acute diarrhoeal illness (ADI) in children under non-outbreak conditions in a major US metropolitan area. We used a nested case-control study of children seen in an urban/suburban emergency department. Cases were those seen for a complaint of diarrhoea, while controls were age-matched children with a non-gastrointestinal complaint. Parents of subjects completed a validated water-use survey. Stratum-specific adjusted odds ratios (aOR) were calculated for the three main water effects: water source [surface vs. ground (well)], drinking-water type (tap vs. bottled), and use of water filters. Of 2472 subjects, 45% drank mostly or only bottled water. Well-water use was associated with increased odds of ADI compared to surface water [aOR 1·38, 95% confidence interval (CI) 1·01–1·87]. Use of bottled water did not affect the odds of ADI in well-water users, but increased the odds of ADI for surface-water users (aOR 1·27, 95% CI 1·02–1·57). We conclude that well-water use and bottled-water use are associated with increased odds of ADI in children.

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HOUSEHOLD WATER BALANCE AND ASSESSMENT OF WATER VOLUME FOR IRRIGATION IN AGRO LANDSCAPES OF THE KYZYLSU-YUZHNAYA BASIN

Prirodoobustrojstvo ◽

10.26897/1997-6011-2020-5-102-109 ◽

2020 ◽

pp. 102-109

Author(s):

D.KH. DOMULLODZHANOV ◽

◽

R. RAHMATILLOEV

Keyword(s):

Water Balance ◽

River Basin ◽

Water Use ◽

Storage Systems ◽

Low Cost ◽

Field Studies ◽

Water Volume ◽

Land Productivity ◽

Household Water ◽

And Storage

The article presents the results of the field studies and observations that carried out on the territory of the hilly, low-mountain and foothill agro landscapes of the Kyzylsu-yuzhnaya (Kyzylsu-Southern) River Basin of Tajikistan. Taking into account the high-altitude location of households and the amount of precipitation in the river basin, the annual volumes of water accumulated with the use of low-cost systems of collection and storage of precipitation have been clarified. The amount of water accumulated in the precipitation collection and storage systems has been established, the volume of water used for communal and domestic needs,the watering of livestock and the amount of water that can be used to irrigate crops in the have been determined. Possible areas of irrigation of household plots depending on the different availability of precipitation have been determined. It has been established that in wet years (with precipitation of about 10%) the amount of water collected using drip irrigation will be sufficient for irrigation of 0.13 hectares, and in dry years (with 90% of precipitation) it will be possible to irrigate only 0.03 ha of the household plot. On the basis of the basin, the total area of irrigation in wet years can be 4497 ha, and in dry years only 1087 ha. Taking into account the forecasts of population growth by 2030 and an increase in the number of households, the total area of irrigation of farmlands in wet years may reach 5703 hectares,and in dry years – 1379 hectares. Growing crops on household plots under irrigation contributes to a significant increase in land productivity and increases the efficiency of water use of the Kyzylsu-yuzhnaya basin.

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Contrasting Water Use Strategies of Tamarix ramosissima in Different Habitats in the Northwest of Loess Plateau, China

Water ◽

10.3390/w12102791 ◽

2020 ◽

Vol 12 (10) ◽

pp. 2791

Author(s):

Pengyan Su ◽

Mingjun Zhang ◽

Deye Qu ◽

Jiaxin Wang ◽

Yu Zhang ◽

...

Keyword(s):

Soil Water ◽

Water Use ◽

Loess Plateau ◽

Meteoric Water ◽

Water Source ◽

Water Sources ◽

Tamarix Ramosissima ◽

Water Line ◽

Meteoric Water Line ◽

Utilization Ratio

As a species for ecological restoration in northern China, Tamarix ramosissima plays an important role in river protection, flood control, regional climate regulation, and landscape construction with vegetation. Two sampling sites were selected in the hillside and floodplain habitats along the Lanzhou City, and the xylems of T. ramosissima and potential water sources were collected, respectively. The Bayesian mixture model (MixSIAR) and soil water excess (SW-excess) were applied to analyze the relationship on different water pools and the utilization ratios of T. ramosissima to potential water sources in two habitats. The results showed that the slope and intercept of local meteoric water line (LMWL) in two habitats were smaller compared with the global meteoric water line (GMWL), which indicated the existence of drier climate and strong evaporation in the study area, especially in the hillside habitat. Except for the three months in hillside, the SW-excess of T. ramosissima were negative, which indicated that xylems of T. ramosissima are more depleted in δ2H than the soil water line. In growing seasons, the main water source in hillside habitat was deep soil water (80~150 cm) and the utilization ratio was 63 ± 17% for T. ramosissima, while the main water source in floodplain habitat was shallow soil water (0~30 cm), with a utilization ratio of 42.6 ± 19.2%, and the water sources were different in diverse months. T. ramosissima has a certain adaptation mechanism and water-use strategies in two habitats, and also an altered water uptake pattern in acquiring the more stable water. This study will provide a theoretical basis for plant water management in ecological environment protection in the Loess Plateau.

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Intensified Interspecific Competition for Water after Afforestation with Robinia pseudoacacia into a Native Shrubland in the Taihang Mountains, Northern China

Sustainability ◽

10.3390/su13020807 ◽

2021 ◽

Vol 13 (2) ◽

pp. 807

Author(s):

Wanrui Zhu ◽

Wenhua Li ◽

Peili Shi ◽

Jiansheng Cao ◽

Ning Zong ◽

...

Keyword(s):

Soil Water ◽

Introduced Species ◽

Water Use ◽

Rainy Season ◽

Robinia Pseudoacacia ◽

Water Source ◽

Total Water ◽

Mountainous Areas ◽

Water Competition ◽

Seasonal Water Use

Understanding how soil water source is used spatiotemporally by tree species and if native species can successfully coexist with introduced species is crucial for selecting species for afforestation. In the rocky mountainous areas of the Taihang Mountains, alien Robinia pseudoacacia L. has been widely afforested into the native shrublands dominated by Ziziphus jujuba Mill var. spinosa and Vitex negundo L. var. heterophylla to improve forest coverage and soil nutrients. However, little is known about the water relation among species, especially seasonal water use sources in different microsites. We selected the soil and plant xylem samples of two opposite microtopographic sites (ridge and valley) monthly in the growth season to analyze isotope composition. The proportions of water sources were quantified by the MixSIAR model and compared pairwise between species, microsites and seasons. We found that deep subsoil water at a depth of 40–50 cm contributed up to 50% of the total water uptake for R. pseudoacacia and Z. jujuba in the growing season, indicating that they stably used deeper soil water and had intense water competition. However, V. negundo had a more flexible water use strategy, which derived more than 50% of the total water uptake from the soil layer of 0–10 cm in the rainy season, but majorly captured soil water at a depth of 30–50 cm in the dry season. Therefore, high niche overlaps were shown in V. negundo with the other two species in the dry season, but niche segregation was seen in the rainy season. The microtopographic sites did not shift the seasonal dynamic of the water source use patterns of the three studied species, but the water use niche overlap was higher in the valley than in the ridge. Taken together, the introduced species R. pseudoacacia intensified water competition with the native semi-arbor species Z. jujuba, but it could commonly coexist with the native shrub species V. negundo. Therefore, our study on seasonal water use sources in different microsites provides insight into species interaction and site selection for R. pseudoacacia afforestation in the native shrub community in rocky mountainous areas. It is better to plant R. pseudoacacia in the shrubland in the valley so as to avoid intense water competition and control soil erosion.

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The role of nature contact and connectedness to nature as determinants of household water use: A case study from Spain

Water and Environment Journal ◽

10.1111/wej.12765 ◽

2021 ◽

Author(s):

Nazaret Ibáñez‐Rueda ◽

Jorge Guardiola ◽

Francisco González‐Gómez

Keyword(s):

Water Use ◽

Connectedness To Nature ◽

Household Water ◽

Nature Contact

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FC 134WATER SAVING COMPARISON AT DIFFERENT DIALYSATE FLOWS IN EXPANDED HEMODIALYSIS

Nephrology Dialysis Transplantation ◽

10.1093/ndt/gfab137.001 ◽

2021 ◽

Vol 36 (Supplement_1) ◽

Author(s):

Alejandra Molano-Triviño ◽

Jasmin Vesga ◽

Gregorio Romero ◽

Claudio Ronco

Keyword(s):

World Health Organization ◽

Water Use ◽

Potable Water ◽

Ecological Impact ◽

World Health ◽

World Population ◽

Dialysate Flow ◽

Middle Molecules ◽

Health Organization ◽

Water Waste

Abstract Background and Aims Expanded hemodialysis (HDx) improves clearance of middle molecules as a target for uremia treatment. According to previously published results, high cut off filters have high enough clearance to allow diminishing of dialysate flow (Qd) without detrimental in HD adequacy outcomes with less water waste. According to World Health Organization (WHO), globally, almost 800 million people lack access to safe water and 2.5 billion lack access to optimal sanitation. Is our duty to search for ways to avoid water waste. Our aim is to describe the differences in water use between HDX patients receiving Qd 400 mL/min (Group 1) vs 500 ml/min (group 2) in HD patients from 10 renal clinics in Colombia as an alternative to reduce water waste in chronic HD as a strategy from Blue Planet Dialysis initiatives. Method We performed a Sub-analysis of CORHEX Study: We calculated water use at different Qd from our database: prospective, multicentre, observational cohort study of 992 adult patients undergoing chronic HD from 12 renal clinics in Colombia who were switched from high-flux HD to MCO therapy and observed for 12 months. All patients were prescribed with HDX three times a week for a minimum of 4 hours. We analysed patients with weight lower than 70 Kg at different Qd prescriptions to calculate water use at different Qd prescriptions and performed a prediction analysis, adjusting to Qd 400 mL/min, the whole potential population with weight lower than 70 Kg. Results 462 patients with weight lower than 70 Kg were analysed, 127 patients received Qd 400 mL/min. When diminishing Qd from 500 to 400 mL/min, 24 litres were saved per session per patient without detriment of middle molecule clearance. There were no differences in adequacy HD parameters between Qd prescriptions (Table 1 and 2). Conclusion HDX allows lowering of Qd to 400 mL/min without harm for patients and with remarkable savings of potable water: 24 Litres were saved in each session per patient that can be translated in almost 3500 Litres of water each year by patient which is enough for one year for 47 adults. (Based on the WHO minimum for basic health protection of at least 20 L per person/day) (2). We consider our results especially relevant since the World Health Organization estimates that within the next 5 years, over 50% of world population could reside in geographies lacking sufficient access to water. We hope that our results from the Blue Planet dialysis research group, alongside with Dr. Agar`s and Dr. Barraclough`s green nephrology initiatives, can help educate the nephrology community on the ecological impact of dialysis and can present an innovative solution to offer HD therapy even in countries suffering from limited access to potable water.

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