Water

443 KiB

Open AccessArticle

by Momi Dahan and Udi Nisan

Water 2011, 3(4), 1174-1196; https://doi.org/10.3390/w3041174 - 16 Dec 2011

Cited by 2 | Viewed by 6535

We use two separate quasi-natural experiments to explore the relative importance of information and administrative costs in explaining non-take-up of water subsidy. The first “experiment” shows that the take-up rate of a household with lower administrative costs is not significantly different from otherwise [...] Read more.

We use two separate quasi-natural experiments to explore the relative importance of information and administrative costs in explaining non-take-up of water subsidy. The first “experiment” shows that the take-up rate of a household with lower administrative costs is not significantly different from otherwise identical households. In contrast, using the same program, the second “experiment” reveals that the take-up rate of a household that is more likely to be informed is substantially higher compared to otherwise identical households. These findings support the idea that information plays a major role in explaining non-take-up of water subsidy. Full article

(This article belongs to the Special Issue Water Policy)

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4504 KiB

Open AccessArticle

The 2011 Brisbane Floods: Causes, Impacts and Implications

by Robin C. Van den Honert and John McAneney

Water 2011, 3(4), 1149-1173; https://doi.org/10.3390/w3041149 - 09 Dec 2011

Cited by 221 | Viewed by 98357

Abstract

On 13th January 2011 major flooding occurred throughout most of the Brisbane River catchment, most severely in Toowoomba and the Lockyer Creek catchment (where 23 people drowned), the Bremer River catchment and in Brisbane, the state capital of Queensland. Some 56,200 claims have [...] Read more.

On 13th January 2011 major flooding occurred throughout most of the Brisbane River catchment, most severely in Toowoomba and the Lockyer Creek catchment (where 23 people drowned), the Bremer River catchment and in Brisbane, the state capital of Queensland. Some 56,200 claims have been received by insurers with payouts totalling $2.55 billion. This paper backgrounds weather and climatic factors implicated in the flooding and the historical flood experience of Brisbane. We examine the time history of water releases from the Wivenhoe dam, which have been accused of aggravating damage downstream. The dam was built in response to even worse flooding in 1974 and now serves as Brisbane’s main water supply. In our analysis, the dam operators made sub-optimal decisions by neglecting forecasts of further rainfall and assuming a ‘no rainfall’ scenario. Questions have also been raised about the availability of insurance cover for riverine flood, and the Queensland government’s decision not to insure its infrastructure. These and other questions have led to Federal and State government inquiries. We argue that insurance is a form of risk transfer for the residual risk following risk management efforts and cannot in itself be a solution for poor land-use planning. With this in mind, we discuss the need for risk-related insurance premiums to encourage flood risk mitigating behaviours by all actors, and for transparency in the availability of flood maps. Examples of good flood risk management to arise from this flood are described. Full article

(This article belongs to the Special Issue Flood Risk Management)

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510 KiB

Open AccessArticle

The Role of Attached and Free-Living Bacteria in Biodegradation in Karst Aquifers

by Roger Painter, Tom Byl, Lonnie Sharpe, Ahmad Kheder and Justin Harris

Water 2011, 3(4), 1139-1148; https://doi.org/10.3390/w3041139 - 08 Dec 2011

Cited by 6 | Viewed by 6558

Abstract

Natural attenuation of groundwater contamination occurs at some level for all aquifers impacted with organic contaminants. The issues regarding natural attenuation are whether it takes place at a sufficient rate to be protective of human health and the environment. Implementation of a Monitored [...] Read more.

Natural attenuation of groundwater contamination occurs at some level for all aquifers impacted with organic contaminants. The issues regarding natural attenuation are whether it takes place at a sufficient rate to be protective of human health and the environment. Implementation of a Monitored Natural Attenuation (MNA) remedial alternative for groundwater requires parties responsible for the contamination to demonstrate to regulators and the public that MNA is protective at a given site. Analysis of MNA for remediation of karst aquifers is hampered by a lack of understanding of biodegradation in karst environments. The lack of studies examining biodegradation in karst aquifers may in large part be due to the widespread perception that contaminants are rapidly flushed out of karst aquifers resulting in insufficient residence times for contaminants to biodegrade. In highly developed and well-connected conduit systems, the rate of contaminant migration is perceived to be much faster than the rate of biodegradation. This perception of contaminant transport is largely incorrect. Tracer studies for karst aquifers often indicate that these aquifers are characterized by diverse flow regimes and storage capabilities. Additionally, it is also believed that if bioremediation in bedrock aquifers is dependent upon contact between surface-attached bacteria and contaminants, then bioremediation would be limited by the low surface-area-to-volume ratio (SA/V) of karst aquifers. A quantitative basis, however, for accepting or rejecting the assumption that attached bacteria dominate the biodegradation process in karst conduits has not been shown. The objective of this research was to determine if free-living karst bacteria from contributed as much to toluene biodegradation as attached bacteria. This is an important area of research. Research indicates bacteria are both attached and free-living in karst aquifers and it is unrealistic to think that only the attached bacteria facilitate biodegradation. The groundwater use in all tests was taken from a karst aquifer know to be impacted by BTEX. The resulting first-order rate constants were computed to be 0.014 per hour for the open system and 0.0155 per hour for the packed reactor system. Biodegradation of toluene in flow-through laboratory karst systems of varying SA/V indicated that the observed biodegradation of toluene was attributable to free-living karst bacteria and not limited by low SA/V in karst. This was evidenced by the fact that the systems with five-fold variation in SA/V were shown to have observed pseudo first order reaction rate constants that differed by only 7.0%. If attached bacteria were primarily responsible for biodegradation and limiting, a proportional difference in the observed rates relative to the difference in surface area would be expected. Full article

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530 KiB

Open AccessArticle

Disinfection of Treated Wastewater and its Reuse in the Irrigation of Golf Grass: The Case of Plant M’zar Agadir-Morocco

by Hind Mouhanni, Abelaziz Bendou and Salah Er-Raki

Water 2011, 3(4), 1128-1138; https://doi.org/10.3390/w3041128 - 08 Dec 2011

Cited by 7 | Viewed by 6294

Abstract

The treated wastewater of Agadir M’zar plant has a good physico-chemical quality and it contains important nutrients (NPK: nitrogen, phosphorus, potassium). However, the reuse of this water, without disinfecting it, for irrigating the golf grass in the Agadir region, revealed the presence of [...] Read more.

The treated wastewater of Agadir M’zar plant has a good physico-chemical quality and it contains important nutrients (NPK: nitrogen, phosphorus, potassium). However, the reuse of this water, without disinfecting it, for irrigating the golf grass in the Agadir region, revealed the presence of a bacterial load that can hinder the quality and suitability of spaces for a population that is very demanding. Among the various methods of water disinfection, chlorination with bleach is the least expensive and the most systematically simple. Its effectiveness depends only on the pH of the waters to be disinfected. This study reports the results of disinfection of M’zar plant wastewater with a solution of sodium hypochlorite (bleach), and their reuse for irrigating the golf grass. For this purpose, we carried out a monitoring protocol for germination and growth parameters (number of tillers and leaf length) in order to study and compare the effect of disinfected treated wastewater (DTWW) and groundwater (GW) on the plant turf. The obtained result showed that the disinfection with bleach increased the salinity of the treated wastewater and can affect the permeability of soils and crops. Full article

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247 KiB

Open AccessArticle

Irrigation of Castor Bean (Ricinus communis L.) and Sunflower (Helianthus annus L.) Plant Species with Municipal Wastewater Effluent: Impacts on Soil Properties and Seed Yield

by Michalis K. Chatzakis, Vasileios A. Tzanakakis, Duncan D. Mara and Andreas N. Angelakis

Water 2011, 3(4), 1112-1127; https://doi.org/10.3390/w3041112 - 24 Nov 2011

Cited by 16 | Viewed by 9021

Abstract

The effects of plant species (castor bean (Ricinus communis L.) versus sunflower (Helianthus annus L.)) and irrigation regime (freshwater versus secondary treated municipal wastewater) on soil properties and on seed and biodiesel yield were studied in a three year pot trial. [...] Read more.

The effects of plant species (castor bean (Ricinus communis L.) versus sunflower (Helianthus annus L.)) and irrigation regime (freshwater versus secondary treated municipal wastewater) on soil properties and on seed and biodiesel yield were studied in a three year pot trial. Plant species were irrigated at rates according to their water requirements with either freshwater or wastewater effluent. Pots irrigated with freshwater received commercial fertilizer, containing N, P, and K, applied at the beginning of each irrigation period. The results obtained in this study showed that irrigation with effluent did not result in significant changes in soil pH, soil organic matter (SOM), total kjeldahl nitrogen (TKN), and dehydrogenase activity, whereas soil available P was found to increase in the upper soil layer. Soil salinity varied slightly throughout the experiment in effluent irrigated pots but no change was detected at the end of the experiment compared to the initial value, suggesting sufficient salt leaching. Pots irrigated with effluent had higher soil salinity, P, and dehydrogenase activity but lower SOM and TKN than freshwater irrigated pots. Sunflower showed greater SOM and TKN values than castor bean suggesting differences between plant species in the microorganisms carrying out C and N mineralization in the soil. Plant species irrigated with freshwater achieved higher seed yield compared to those irrigated with effluent probably reflecting the lower level of soil salinity in freshwater irrigated pots. Castor bean achieved greater seed yield than sunflower. Biodiesel production followed the pattern of seed yield. The findings of this study suggest that wastewater effluent can constitute an important source of irrigation water and nutrients for bioenergy crop cultivations with minor adverse impacts on soil properties and seed yield. Plant species play an important role with regard to the changes in soil properties and to the related factors of seed and biodiesel yields. Full article

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1633 KiB

Open AccessArticle

Evaluation of Soil Sensitivity towards the Irrigation with Treated Wastewater in the Jordan River Region

by Karsten Schacht, Sven Gönster, Elisabeth Jüschke, Yona Chen, Jorge Tarchitzky, Jawad Al-Bakri, Emad Al-Karablieh and Bernd Marschner

Water 2011, 3(4), 1092-1111; https://doi.org/10.3390/w3041092 - 24 Nov 2011

Cited by 13 | Viewed by 7157

Abstract

An assessment of soil sensitivity was carried out regarding the soil suitability for wastewater reuse. This was done based on digital soil maps joined with spatial data on soil properties using Geographic Information Systems (GIS). Six major risks of primarily agricultural significance were [...] Read more.

An assessment of soil sensitivity was carried out regarding the soil suitability for wastewater reuse. This was done based on digital soil maps joined with spatial data on soil properties using Geographic Information Systems (GIS). Six major risks of primarily agricultural significance were defined in close collaboration with regional experts. The changes in particular soil and groundwater properties as a result of irrigation with low water quality were evaluated and discussed. Based on the local soil parameters, the specific sensitivity and suitability grades were assessed for the respective soil unit concerning irrigation with treated wastewater (TWW) using standard and specially developed methods. In conclusion, with regard to soil suitability criteria, sensitivity and suitability maps, including the aggregated total sensitivity, were presented for supporting sustainable irrigation practices. Full article

(This article belongs to the Special Issue Water Recycling and Reuse)

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302 KiB

Open AccessArticle

Optimal Level of Groundwater Charge to Promote Rainwater Usage for Irrigation in Rural Beijing

by Xiao Liang and Meine Pieter van Dijk

Water 2011, 3(4), 1077-1091; https://doi.org/10.3390/w3041077 - 14 Nov 2011

Cited by 2 | Viewed by 5620

Abstract

Since groundwater is diminishing rapidly in rural Beijing, rainwater harvesting for irrigation is being promoted. As the cost of pumping up groundwater is low, farmers have few incentives to use rainwater. To promote the consumption of rainwater, the Beijing Water Authority may in [...] Read more.

Since groundwater is diminishing rapidly in rural Beijing, rainwater harvesting for irrigation is being promoted. As the cost of pumping up groundwater is low, farmers have few incentives to use rainwater. To promote the consumption of rainwater, the Beijing Water Authority may in the future raise the cost of using groundwater by introducing a charge. Higher cost of groundwater will increase the consumption of rainwater, but can have a negative impact on farmers’ incomes. This paper aims to study how to increase rainwater consumption without discouraging farming. The relation between the cost of groundwater and the consumption of rainwater has been studied by analyzing the elasticity of groundwater demand graphically. If the cost of groundwater is lower than the elasticity threshold, farmers lack incentives to use rainwater. If the cost of groundwater is higher than the threshold, rainwater consumption increases. The elasticity threshold of groundwater can move down following a change in the characteristics of rainwater harvesting systems. With linear programming analysis it has been found that increasing subsidies and enlarging the size of rainwater harvesting systems decreases the elasticity threshold of groundwater. This results in a proposal for a realistic charge for groundwater, affecting the consumption of rainwater but also taking into account the income of the farmers. Full article

(This article belongs to the Special Issue Water Recycling and Reuse)

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1901 KiB

Open AccessArticle

Arsenic Contamination in Groundwater of Bangladesh: Perspectives on Geochemical, Microbial and Anthropogenic Issues

by Hossain M. Anawar, Junji Akai, Martin Mihaljevič, Arif M. Sikder, Golam Ahmed, Shafi M. Tareq and Mohammad M. Rahman

Water 2011, 3(4), 1050-1076; https://doi.org/10.3390/w3041050 - 11 Nov 2011

Cited by 50 | Viewed by 9978

Abstract

A groundwater, sediment and soil chemistry and mineralogical study has been performed to investigate the sources and mobilization process of Arsenic (As) in shallow aquifers of Bangladesh. The groundwater from the shallow aquifers is characterized by high concentrations of Arsenic (47.5–216.8 µg/L), iron [...] Read more.

A groundwater, sediment and soil chemistry and mineralogical study has been performed to investigate the sources and mobilization process of Arsenic (As) in shallow aquifers of Bangladesh. The groundwater from the shallow aquifers is characterized by high concentrations of Arsenic (47.5–216.8 µg/L), iron (0.85–5.83 mg/L), and phosphate, along with high electrical conductivity (EC). The groundwater has both very low oxidation-reduction potential (Eh) and dissolved oxygen (DO) values indicating reducing conditions. By contrast, the deep aquifers and surface waters (pond, canal) have very low concentrations of Arsenic ( < 6 µg/L), iron (0.12–0.39 mg/L), and phosphate along with a relatively low EC. Furthermore, the values of Eh and DO are high, indicating oxic to suboxic conditions. Arsenic is inversely correlated with Eh values in the upper aquifer, whereas no relationship in the deeper aquifer is observed. These results suggest that As mobilization is clearly linked to the development of reducing conditions. The clayey silt, enriched in Fe, Mn, Al oxides and organic matter, and deposited in the middle unit of shallow aquifers, contains moderately high concentrations of As, whereas the sediments of deep aquifers and silty mud surface soils from paddy fields and ponds contain a low content of As (Daudkandi area). Arsenic is strongly correlated with the concentrations of Fe, Mn and Al oxides in the core samples from the Daudkandi and Marua areas. Arsenic is present in the oxide phase of Fe and Mn, phyllosilicate minerals and in organic matter in sediments. This study suggests that adsorption or precipitation of As-rich Fe oxyhydroxide on the surface or inner sites of biotite might be responsible for As concentrations found in altered biotite minerals by Seddique et al. Microbially or geochemically mediated reductive dissolution of Fe oxyhydroxides is the main mechanism for As release. The reducing conditions are caused by respiratory decomposition of organic matter, either sedimentary or labile organic C. The process can be accelerated by agricultural activity and domestic organic wastes. An agricultural fertilizer can directly contribute As to groundwater as well as promote As mobilization by ion-exchange with phosphorus. Full article

(This article belongs to the Special Issue Inorganic Pollution of Water Environment)

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349 KiB

Open AccessArticle

Profitability of Nitrification Inhibitors for Abatement of Nitrate Leaching on a Representative Dairy Farm in the Waikato Region of New Zealand

by Graeme J. Doole and Upa H. Paragahawewa

Water 2011, 3(4), 1031-1049; https://doi.org/10.3390/w3041031 - 11 Nov 2011

Cited by 5 | Viewed by 7242

Abstract

Direct policies for the management of nonpoint source pollution are difficult to apply given asymmetric information, spatial and temporal variability, and uncertainty. There is increasing awareness that these limitations may be overcome where profitable mitigation practices are broadly adopted by polluters. Nitrification inhibitors [...] Read more.

Direct policies for the management of nonpoint source pollution are difficult to apply given asymmetric information, spatial and temporal variability, and uncertainty. There is increasing awareness that these limitations may be overcome where profitable mitigation practices are broadly adopted by polluters. Nitrification inhibitors (chemicals applied to paddocks that retard the nitrification process in soils) are a rare example of a mitigation practice that reduces pollutant loads and potentially increases farm profit through promoting pasture production. This study investigates their capacity to achieve both goals to inform policy makers and producers of their potential for simultaneously improving farm profit and water quality. With an assumed 10 percent increase in pasture production in response to nitrification inhibitor application, nitrification inhibitors are a profitable innovation because greater pasture production supports higher stocking rates. Nonetheless, their overall impact on farm profit is low, even when the cost of inhibitors or their impact on subsequent pasture production is substantially altered. However, inhibitors are found to be a critical mitigation practice for farmers posed with decreasing leaching loads to satisfy regulatory requirements. These findings suggest that, despite their shortcomings for nonpoint pollution regulation, direct policies appear to be the only way to motivate producers to account for their impact on environmental values given the current lack of profitable mitigations. Full article

(This article belongs to the Special Issue Water Policy)

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385 KiB

Open AccessReview

The Impact of Ocean Acidification on Reproduction, Early Development and Settlement of Marine Organisms

by Pauline M. Ross, Laura Parker, Wayne A. O’Connor and Elizabeth A. Bailey

Water 2011, 3(4), 1005-1030; https://doi.org/10.3390/w3041005 - 07 Nov 2011

Cited by 139 | Viewed by 15065

Abstract

Predicting the impact of warming and acidifying on oceans on the early development life history stages of invertebrates although difficult, is essential in order to anticipate the severity and consequences of future climate change. This review summarises the current literature and meta-analyses on [...] Read more.

Predicting the impact of warming and acidifying on oceans on the early development life history stages of invertebrates although difficult, is essential in order to anticipate the severity and consequences of future climate change. This review summarises the current literature and meta-analyses on the early life-history stages of invertebrates including fertilisation, larval development and the implications for dispersal and settlement of populations. Although fertilisation appears robust to near future predictions of ocean acidification, larval development is much more vulnerable and across invertebrate groups, evidence indicates that the impacts may be severe. This is especially for those many marine organisms which start to calcify in their larval and/or juvenile stages. Species-specificity and variability in responses and current gaps in the literature are highlighted, including the need for studies to investigate the total effects of climate change including the synergistic impact of temperature, and the need for long-term multigenerational experiments to determine whether vulnerable invertebrate species have the capacity to adapt to elevations in atmospheric CO₂over the next century. Full article

(This article belongs to the Special Issue Impact of Ocean Acidification on Marine Organisms—Unifying Principles and New Paradigms)

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647 KiB

Open AccessArticle

Wastewater Reuse Planning in Agriculture: The Case of Aitoloakarnania, Western Greece

by Ioannis K. Kalavrouziotis, Christos Arambatzis, Dimitrios Kalfountzos and Soterios P. Varnavas

Water 2011, 3(4), 988-1004; https://doi.org/10.3390/w3040988 - 20 Oct 2011

Cited by 17 | Viewed by 7299

Abstract

In the present paper, the possibility of the treated municipal wastewater (TMWW) reuse in agriculture, produced by the Wastewater Treatment Plants of Aitoloakarnania prefecture, one of the greatest agricultural regions of Greece, has been investigated. The boundaries of agricultural soils and the irrigated [...] Read more.

In the present paper, the possibility of the treated municipal wastewater (TMWW) reuse in agriculture, produced by the Wastewater Treatment Plants of Aitoloakarnania prefecture, one of the greatest agricultural regions of Greece, has been investigated. The boundaries of agricultural soils and the irrigated crops were defined, and the water requirements of crops were calculated. Also the chemical characteristics of the TMWW were determined for the safe reuse in crop production, and for the protection of soils from potential pollution. The research conducted in this area is expected to constitute the basis for an integrated TMWW reuse planning in soils and crops, in the context of sustainable agriculture, and environmental protection. It must be mentioned that the Messolongion-Aitolikon lagoon is in the area under investigation, one of the largest wetland ecosystem of Mediterranean region, which makes the area ecologically sensitive. The ultimate scope of this study is to describe the planning of the TMWW reuse on the basis of soil characteristics, climatic factors, and irrigation water requirements of the crops, grown in this ecologically sensitive area. The volume of the effluents produced by the wastewater treatment plants of Messolonghion, Agrinion, Nafpaktos, Aitoliko and Thermo could cover 19.3%, 25.14%, >100%, 17.18 and 87.84% of the irrigation water requirements, respectively. Full article

(This article belongs to the Special Issue Water Recycling and Reuse)

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310 KiB

Open AccessArticle

Framework for Enhancing the Supply-Demand Balance of a Tri-Supply Urban Water Scheme in Australia

by Edoardo Bertone and Rodney A. Stewart

Water 2011, 3(4), 976-987; https://doi.org/10.3390/w3040976 - 13 Oct 2011

Cited by 3 | Viewed by 6806

Abstract

Fit-for-purpose potable source substitution of appropriate water end uses with rainwater or recycled water is often essential to maintain water security in growing urban regions. This paper provides the results of a detailed supply-demand forecasting review of a unique tri-supply (i.e., [...] Read more.

Fit-for-purpose potable source substitution of appropriate water end uses with rainwater or recycled water is often essential to maintain water security in growing urban regions. This paper provides the results of a detailed supply-demand forecasting review of a unique tri-supply (i.e., potable, A+ recycled and rain water sources reticulated to household) urban water scheme located in Queensland, Australia. Despite the numerous benefits of this scheme, system efficiency (e.g., reduced demand levels, water treatment, low chemical and energy use) and economic viability (i.e., capital and operating costs per kL of supply) aspects need to be considered against derived potable water savings. The review underpinned the design of a framework to enhance the schemes supply-demand balance and reduce the unit cost of alternative source supplies. Detailed scenario and sensitivity analysis identified the possibility of a refined scheme design, whereby the A+ recycled water supply would be reticulated to the cold water input tap to the washing machine, and the rain tank that originally supplied this end use be removed from future constructed households. The refined scheme design enhances the present recycled plant utilisation rate and reduces the cost to home owners when building their dwelling due to the removed requirement to install a rain tank to indoor end uses; such actions reduce the overall unit cost of the scheme. Full article

(This article belongs to the Special Issue Water Recycling and Reuse)

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2357 KiB

Open AccessReview

Artificial Recharge via Boreholes Using Treated Wastewater: Possibilities and Prospects

by Kostas Voudouris

Water 2011, 3(4), 964-975; https://doi.org/10.3390/w3040964 - 26 Sep 2011

Cited by 19 | Viewed by 9332

Abstract

Interest in artificial recharge of groundwater using pretreated wastewater continues to increase, especially in semi-arid countries. After the artificial recharge and natural treatment, the water could be extracted through boreholes pumping for direct irrigation. The selection of suitable locations for artificial recharge should [...] Read more.

Interest in artificial recharge of groundwater using pretreated wastewater continues to increase, especially in semi-arid countries. After the artificial recharge and natural treatment, the water could be extracted through boreholes pumping for direct irrigation. The selection of suitable locations for artificial recharge should be based on hydrogeological conditions, economic evaluation and environmental considerations. Clogging of boreholes that are used for artificial recharge is a serious problem and requires proper planning to reduce it. This paper deals with the investigation of the possibilities and prospects of aquifer recharge via boreholes using treated wastewater. Firstly, the aquifer recharge techniques, the proposed criteria of waste and the clogging effect are presented. Secondly, the possibility of application of artificial recharge in the South-Eastern Mesaoria aquifer of Cyprus is examined. Based on hydrogeological results, artificial recharge using tertiary treated wastewater via boreholes is one of the options available for increasing the groundwater reserves of this aquifer. The recycled water will infiltrate through gravel pack, providing favorable conditions for ventilation and laminar flow due to small water flow velocity. The treatment works include the removal of the fat, oil and grease (FOG) and cyanides (CN⁻) content in order to meet the upper acceptable limits. Full article

(This article belongs to the Special Issue Water Recycling and Reuse)

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Water, Volume 3, Issue 4 (December 2011) – 13 articles , Pages 964-1196

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