Rainwater Tanks as a Means of Water Reuse and Conservation in Urban Areas

The objective of this work is to assess the potentials and requirements for grey water reuse in Jordan. The results revealed that urban, rural and dormitory grey water production rate and concentration of TS, BOD5, COD and pathogens varied between 18–66 L cap−1d−1, 848–1,919, 200–1,056, and 560–2,568 mg L−1 and 6.9E2–2.7E5 CFU mL−1, respectively. The grey water compromises 64 to 85% of the total water flow in the rural and urban areas. Storing grey water is inevitable to meet reuse requirements in terms of volume and timing. All the studied grey waters need treatment, in terms of solids, BOD5, COD and pathogens, before storage and reuse. Storage and physical treatment, as a pretreatment step should be avoided, since it produces unstable effluents and non-stabilized sludge. However, extensive biological treatment can combine storage and physical treatments. Furthermore, a batch-fed biological treatment system combining anaerobic and aerobic processes copes with the fluctuations in the hydrographs and pollutographs as well as the present nutrients. The inorganic content of grey water in Jordan is about drinking water quality and does not need treatment. Moreover, the grey water SAR values were 3–7, revealing that the concentrations of monovalent and divalent cations comply with agricultural demand in Jordan. The observed patterns in the hydrographs and pollutographs showed that the hydraulic load could be used for the design of both physical and biological treatment units for dormitories and hotels. For family houses the hydraulic load was identified as the key design parameter for physical treatment units and the organic load is the key design parameter for biological treatment units.

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Evaluation of a portable in-house greywater treatment system for potential water-reuse in urban areas

Urban Water Journal ◽

10.1080/1573062x.2018.1457165 ◽

2018 ◽

Vol 15 (4) ◽

pp. 309-315 ◽

Cited By ~ 6

Author(s):

Shashi Kant ◽

Fouad H. Jaber ◽

R. Karthikeyan

Keyword(s):

Urban Areas ◽

Water Reuse ◽

Treatment System

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An investigation of rainwater tanks quality and sediment dynamics

Water Science & Technology ◽

10.2166/wst.2007.738 ◽

2007 ◽

Vol 56 (9) ◽

pp. 21-28 ◽

Cited By ~ 23

Author(s):

M.I. Magyar ◽

V.G. Mitchell ◽

A.R. Ladson ◽

C. Diaper

Keyword(s):

Urban Areas ◽

Sediment Resuspension ◽

Pilot Scale ◽

Transport Processes ◽

Full Scale ◽

Quality Of Water ◽

High Concentrations ◽

Future Work ◽

Supply Systems ◽

Rainwater Tanks

Rainwater tanks are being introduced into urban areas in Australia to supplement centralised potable supply systems. A pilot scale tank study and a full-scale field tank study found that heavy metal concentrations in water samples taken from the tank's supply point can, in some cases, exceed levels recommended by guidelines. Both studies also found very high concentrations of heavy metals in the sediments accumulated at the base of rainwater tanks. Laboratory experiments are underway to investigate sediment transport processes within a full-scale tank. Preliminary results demonstrate the effect of sediment resuspension on the quality of water released from the tank outlet. Improved tank designs that reduce sediment resuspension and mitigate impacts on water quality are the focus of future work.

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Revisiting Soil Aquifer Treatment: Improving Biodegradation and Filtration Efficiency Using a Highly Porous Material

Water ◽

10.3390/w12123593 ◽

2020 ◽

Vol 12 (12) ◽

pp. 3593

Author(s):

Joshua Brooks ◽

Noam Weisbrod ◽

Edo Bar-Zeev

Keyword(s):

Porous Material ◽

Urban Areas ◽

Water Reuse ◽

Filtration Efficiency ◽

Natural Material ◽

Soil Aquifer Treatment ◽

Bacterial Phyla ◽

Custom Made ◽

Highly Porous ◽

Highly Porous Material

Soil aquifer treatment (SAT) is an established and sustainable wastewater treatment approach for water reuse that has been gaining increased attention in various countries around the world. Increasing volumes of domestic wastewater and escalating real estate prices around urban areas emphasize the urgent need to maximize the treatment efficiency by revisiting the SAT setup. In this study, a novel approach was examined to increase biodegradation rates and improve the quality of SAT topsoil effluent. Experiments with midscale, custom-made columns were carried out with sand collected from an operational SAT and a highly permeable natural material with high internal porosity, tuff, which was maturated (i.e., buried in the SAT infiltration basin) for 3 months. The filtration efficiency, biodegradation rates of organic material, microbial diversity, and outflow quality were compared between the operational SAT sand and the tuff using state-of-the-art approaches. The results of this study indicate that biodegradation rates (9.2 µg C g−1d−1) and filtration efficiency were up to 2.5-fold higher within the tuff than the SAT sand. Furthermore, the biofilm community was markedly different between the two media, giving additional insights into the bacterial phyla responsible for biodegradation. The results highlight the advantage of using highly porous material to enhance the SAT filtration efficiency without extending the topsoil volume. Hence, infusing a permeable medium, comprising highly porous material, into the SAT topsoil could offer a simple approach to upgrade an already advantageous SAT in both developed and developing countries.

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Semi-centralised supply and treatment systems for (fast growing) urban areas

Water Science & Technology ◽

10.2166/wst.2007.021 ◽

2007 ◽

Vol 55 (1-2) ◽

pp. 349-356 ◽

Cited By ~ 18

Author(s):

B. Weber ◽

P. Cornel ◽

M. Wagner

Keyword(s):

Water Supply ◽

Rapid Growth ◽

Urban Areas ◽

Water Reuse ◽

The Other ◽

Optimal Size ◽

Local Supply ◽

The One ◽

Sanitation Systems ◽

Mega Cities

Mega cities with rapid growth are challenged by two main problems concerning water supply and sanitation. One is water scarcity because local demand exceeds local supply. The other is that the infrastructure for water supply and the collection and treatment of wastewater cannot keep up with the rapid growth of the mega cities. The transfer of conventional centralised water and wastewater systems from industrialised countries to mega cities does not seem appropriate, because of the rapid and almost unpredictable growth in mega cities on the one hand and the regional shortage of water which requires an economical use and reuse wherever possible on the other hand. The transition from centralised to semi-centralised supply and treatment systems (SESATS) may be one method of resolution to the grave discrepancy between the rapid growth of cities and the provision of supply and treatment infrastructure. One important aspect of planning semi-centralised wastewater collection and treatment infrastructure including intra-urban water reuse is the assessment of the optimal size. Therefore, factors and indicators, which have an effect on the scale of semi-centralised sanitation systems, have to be developed. Beside the introduction in SESATS some of these factors, criteria and indicators and their effects on the system's scale will be introduced in this paper.

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Decentralised urban water reuse: The implications of system scale for cost and pathogen risk

Water Science & Technology ◽

10.2166/wst.2002.0690 ◽

2002 ◽

Vol 46 (6-7) ◽

pp. 281-288 ◽

Cited By ~ 25

Author(s):

S.A. Fane ◽

N.J. Ashbolt ◽

S.B. White

Keyword(s):

Urban Areas ◽

Water Reuse ◽

Large Scale ◽

Economies Of Scale ◽

Sewage Treatment ◽

Urban Water ◽

Waterborne Disease ◽

Potable Reuse ◽

Effluent Reuse ◽

Wastewater Systems

The non-potable reuse of treated sewage in urban areas provides significant conservation of potable supplies beyond that available through water use efficiency. Effluent reuse is also an inevitable requirement in novel decentralised wastewater systems. At present, urban water reuse, where pursued, usually involves large-scale schemes based on new or existing centralised sewage treatment plants. This is despite the diseconomy of scale inherent in pipe networks that balances economies of scale in sewage treatment and negates any cost advantage for wastewater systems with more than around 1,000 connections. In light of this, the theoretical relationship between effluent reuse system scale and pathogen risks was examined at various effluent qualities. Waterborne disease was seen to be a significant factor when reusing effluent in urban areas and smaller systems were found to pose a lower risk of waterborne infection, all other things being equal. Pathogen risks were then included within an economic analysis of system scale. It was concluded that with the inclusion of pathogen risks as a costed externality, taking a decentralised approach to urban water reuse would be economically advantageous in most cases. This conclusion holds despite an exact evaluation of increased waterborne disease due to effluent reuse remaining problematic.

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