Water

The wastewater sector paradigm is shifting from wastewater treatment to resource recovery. In addition, concerns regarding sustainability during the operation have increased. In this sense, there is a need to break barriers (i.e., social, economic, technological, legal, etc.) for moving forward towards water resource recovery facilities and demonstration case studies can be very effective and insightful. This paper presents a new water resource recovery case study which is part of the Horizon 2020 EU Project “Achieving wider uptake of water-smart solutions—Wider Uptake”. The final aim is to demonstrate the importance of a resource recovery system based on the circular economy concept. The recovery facilities at Palermo University (Italy) are first presented. Afterwards, the resource recovery pilot plants are described. Preliminary results have underlined the great potential of the wastewater treatment plant in terms of resources recovery and the central role of the University in fostering the transition towards circular economy. The fermentation batch test highlighted a volatile fatty acids (VFAs) accumulation suitable for polyhydroxyalkanoates (PHAs) production. The results of static adsorption and desorption tests showed that the highest amount of adsorbed NH₄⁺ was recorded for untreated and HCl-Na treated clinoptilolite. Full article

Severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) was detected in Wuhan, China. The clinical manifestation of COVID-19 varies from asymptomatic to severe infection. The World Health Organization has reported over 248 million cases and more than 5 million deaths worldwide due to COVID-19. Additionally, developing countries are still struggling to achieve the rapid diagnosis of suspected cases to break the chain of transmission of COVID-19. There may be undiagnosed or missing cases in these countries. Various studies have reported that the SARS-CoV-2 can be discharged in the stool and other bodily fluids. Moreover, it is possible that SARS-CoV-2 can be transmitted in the environment via municipal wastewater. In developing countries, such as Nepal, the molecular-based diagnosis of SARS-CoV-2 for the entire population is not practical owing to insufficient diagnostic material and budgetary constraints. Wastewater-based epidemiology (WBE) is a promising public health surveillance tool for the early warning of disease outbreaks and the understanding the prevalence of viruses for the development of intervention measures. This study highlights the importance of the utilization of WBE as an alternative tool for the mass detection of SARS-CoV-2 RNA in wastewater. Full article

This study identified summer and annual drought events using the Standard Precipitation Index (SPI) for 107 stations across Nepal from 1977 to 2018. For this, frequency, duration, and severity of drought events were investigated. The SPI4 and SPI12 time scales were interpolated to illustrate the spatial patterns of major drought episodes and their severity. A total of 13 and 24 percent of stations over the country showed a significant decreasing trend for SPI4 and SPI12. Droughts were recorded during El Niño and non-El Niño years in Nepal. Among them, 1992 was the worst drought year, followed by the drought year, 2015. More than 44 percent of the locations in the country were occupied under drought conditions during these extreme drought events. Droughts have been recorded more frequently in Nepal since 2005. The areas of Nepal affected by extreme, severe, and moderate drought in summer were 8, 9, and 18 percent, while during annual events they were 7, 11, and 17 percent, respectively. Generally, during the drought years, the SPI and Southern Oscillation Index (SOI) have a strong phase relation compared to the average years. Full article

Hydropower, as a renewable energy resource, has become an important way to fit for Chinese long-term energy policy of energy transformation. Engineering–procurement–construction (EPC) has been increasingly adopted for improving hydropower project delivery efficiency in the utilization of water resources and generation of clean energy, where design plays a critical role in project success. Existing studies advocate the need to use partnering for better solutions to designs in EPC hydropower projects. However, there is a lack of a theoretical framework to systematically address design-related issues considering different participants’ interactions. This study coherently examined the causal relationships among partnering, design management, design capability, and EPC hydropower project performance by establishing and validating a conceptual model, with the support of data collected from a large-scale EPC hydropower project. Path analysis reveals that partnering can directly promote design management and design capability and exert an effect on design capability through enhancing design management, thereby achieving better hydropower project outcomes. This study’s contribution lies in that it theoretically builds the links between intra- and inter-organizational design-related activities by systematically mapping EPC hydropower project performance on partnering, design management, and design capability. These findings also suggest broad practical strategies for participants to optimally integrate their complementary resources into designs to achieve superior hydropower project performance. Full article

The newly developed WRF-Hydro model is a fully coupled atmospheric and hydrological processes model suitable for studying the intertwined atmospheric hydrological processes. This study utilizes the WRF-Hydro system on the Three-River source region. The Nash-Sutcliffe efficiency for the runoff simulation is 0.55 compared against the observed daily discharge amount of three stations. The coupled WRF-Hydro simulations are better than WRF in terms of six ground meteorological elements and turbulent heat flux, compared to the data from 14 meteorological stations located in the plateau residential area and two flux stations located around the lake. Although WRF-Hydro overestimates soil moisture, higher anomaly correlation coefficient scores (0.955 versus 0.941) were achieved. The time series of the basin average demonstrates that the hydrological module of WRF-hydro functions during the unfrozen period. The rainfall intensity and frequency simulated by WRF-Hydro are closer to global precipitation mission (GPM) data, attributed to higher convective available potential energy (CAPE) simulated by WRF-Hydro. The results emphasized the necessity of a fully coupled atmospheric-hydrological model when investigating land-atmosphere interactions on a complex topography and hydrology region. Full article

Under the condition of a large dip angle between the flood discharging structure axis and the downstream cushion pool centerline, the downstream flow connection for the discharging tunnel group is poor, and the lower air pressure in high-altitude areas increases its influence on the trajectory distance of the nappe, further increasing the difficulty of predicting the flood discharge and energy dissipation layout. Based on the RM hydropower project with the world’s highest earth-rockfill dam, this paper studies the problem of a large included angle flip energy dissipation layout of a tunnel group flood discharge using the method of the overall hydraulic physical model test. The test results show that the conventional flip outlet mode has a long nappe falling point, a serious shortage of effective energy dissipation space, a large dynamic hydraulic pressure impact peak value on the bottom slab and side wall of the plunge pool, a poor flow connection between the outlet of the plunge pool and the downstream river channel, and a low energy dissipation rate. Considering the influence of a low-pressure environment, when the “transverse diffusion and downward incidence” outflow is adopted, the nappe falling point shrinks by 11 m, the energy dissipation form of the plunge pool is greatly improved, the effective energy dissipation space is increased by 159%, the RMS of the maximum fluctuating pressure is reduced by 74%, the outflow is smoothly connected with the downstream river, the energy dissipation rate is increased by 0.8%, and the protection range of flood discharge atomization is significantly reduced. This effectively solves the safety problems of large included angle discharge return channels and the energy dissipation and erosion prevention of super-high rockfill dams. Full article

Membrane systems are increasingly being used for treating water, wastewater, and reused water. However, membrane damage can decrease removal efficiency and hinder downstream applicability. Thus, the operating conditions of the membrane should be monitored. This study monitored the operating conditions of the membrane using lead zirconate titanate (PZT)-based electro-mechanical impedance (EMI) measurements in an external air pipe. Pilot-scale tests were performed to verify the performance of the proposed method. A pressure decay test (PDT) was performed using a PZT-attached air pipe, in which the pressure was measured using PZT, and a pressure gauge was employed to measure the reference pressure. The EMI signals changed according to the variations in the pressure inside the steel air pipe. To index the signal variation, the amplitude of the major peak was extracted and compared with the reference pressure. The amplitude of the major peak was inversely proportional to the pressure change. The pressure estimation equation was derived using a linear regression between the amplitudes of the major peak and the reference pressures. According to the results, the proposed monitoring system that utilizes the EMI of an external steel pipe is a potential solution to improve the sensitivity and speed of the PDT. Full article

The Ogallala Aquifer underlies 45 million ha, providing water for approximately 1.9 million people and supporting the robust agriculture economy of the US Great Plains region. The Ogallala Aquifer has experienced severe depletion, particularly in the Southern Plains states. This paper presents policy innovations that promote adoption of irrigation technology, and management innovations. Innovation in Kansas water policy has had the dual effects of increasing the authority of the state to regulate water while also providing more flexibility and increasing local input to water management and regulation. Technology innovations have focused on improved timing and placement of water. Management innovations include soil water monitoring, irrigation scheduling, soil health management and drought-tolerant varieties, crops, and cropping systems. The most noted success has been in the collective action which implemented a Local Enhanced Management Area (LEMA), which demonstrated that reduced water pumping resulted in low to no groundwater depletion while maintaining net income. Even more encouraging is the fact that irrigators who have participated in the LEMA or other conservation programs have conserved even more water than their goals. Innovative policy along with creative local–state–federal and private–public partnerships are advancing irrigation technology and management. Flexibility through multi-year allocations, banking of water not used in a given year, and shifting water across multiple water rights or uses on a farm are promising avenues to engage irrigators toward more sustainable irrigation in the Ogallala region. Full article

Wastewater is actively used for irrigation of vegetable and forage crops in arid lands due to water scarcity and cost advantages. The objective of this review was to assess the effect of wastewater (mixture sources) reuse in irrigation on soil, crop (vegetable and forage crops), animal products, and human health. The metadata analysis of 95 studies revealed that the mean of toxic heavy metals including nickel (Ni), chromium (Cr), cadmium (Cd), lead (Pb), and zinc (Zn) in untreated wastewater were higher than the world standard limits in wastewater-irrigated regions. Although heavy metals in treated wastewater were within the standard limits in those areas, the concentration of those toxic elements (Pb, Cd, Ni, Cr, and As) exceeded the allowable limits in both soil and vegetables’ edible parts. In fact, the concentration of heavy metals in vegetables’ edible parts increased by 3–9 fold when compared with those irrigated with fresh water. Escherichia coli in wastewater-irrigated soil was about 2 × 10⁶ (CFU g⁻¹) and about 15 (CFU g⁻¹) in vegetables’ edible parts (leaf, bulb, tuber and fruit) while the mean total coliforms was about 1.4 × 10⁶ and 55 (CFU g⁻¹) in soil and vegetables’ edible parts, respectively. For human health risk assessment, the estimated daily intake (EDI) and human health risk index (HRI) ranged from 0.01 to 8 (EDI and HRI > 1.0 associated with adverse health effects). Although the mean of EDI for heavy metals from wastewater-irrigated vegetables were less than 1, the HRI for Cd and Pb were above the limits for safe consumption. Overall, heavy metal levels in wastewater that used for irrigation of agricultural crops could be within the recommended levels by the world standards, but the long-term use of this reused water will contaminate soil and crops with several toxic heavy metals leading to potential carcinogenic risks to humans. Therefore, rigorous and frequent testing (wastewater, soil, and plant) is required in cultivated farms to prevent the translocation of heavy metals in the food chain. Full article

Environmental pollution has been a major concern in recent times, and soil and groundwater pollution are areas which have received particular focus. This has led to the development of various remediation techniques such as excavation, soil vapor extraction, bioremediation, chemical oxidation, and so on. Among all remediation techniques, chemical oxidation has been proven to be the most effective and feasible technique around the world. In this study, various combinations of ozone and hydrogen peroxide were used to treat diesel-contaminated soil and groundwater in an experimental setup. Experimental soil and groundwater were prepared with properties similar to the contaminated soil. An ozone generator and a pump injection system were deployed for combining ozone and hydrogen peroxide. Five different experiment batches were prepared based on the hydrogen peroxide concentration and its ratio to the soil. The diesel concentration in the water dropped from 300 mg/L to 7 mg/L in the first hour of treatment, which dropped below the detection limit (0.01 mg/L) thereafter. Similarly, 63.9% degradation was achieved with the combined sparging of ozone and hydrogen peroxide in the soil. Ozone combined with 7% hydrogen peroxide was the most promising combination for removing the contaminants. In addition, this research explored the hydroxyl radical conversion rate of ozone and the perozone, the difference in order of magnitude is greater than one which shows that the perozone has better oxidation capacity than ozone only. The findings of this study show that combining ozone with hydrogen peroxide is a competent and feasible onsite remediation method for diesel contaminants in soil and groundwater. Thus, this method can be applied in local gas stations, accidental spillage sites, and small-scale refineries for onsite treatment in a cost-effective and technically sound way within a short time span. Full article

Advancement of modern technologies has given numerical simulations a crucial role to effectively manage irrigation. A new numerical scheme to determine irrigation depths was incorporated into WASH 2D, which is a numerical simulation model of crop response to irrigation. Based on two predicted points of cumulative transpiration—water price and quantitative weather forecast—the scheme can optimize an irrigation depth in which net income is maximized. A field experiment was carried out at the Arid Land Research Center, Tottori, Japan, in 2019, to evaluate the effectiveness of the scheme on net income and crop production compared to a tensiometer-based automated irrigation system. Sweetcorn (Zea mays L., Amaenbou 86) was grown in three water balance lysimeters per each treatment, filled with sandy soil. The scheme could achieve a 4% higher net income, due to a 7% increase in green fodder yield, and an 11% reduction in irrigation amount, compared with the automated irrigation method. These results indicate that the numerical scheme, in combination with quantitative weather forecasts, can be a useful tool to determine irrigation depths, maximize net incomes which are farmers’ targets, and avoid large investments that are required for the automated irrigation system. Full article

River contamination is due to a chemical mixture of point and diffuse pollution, which can compromise water quality. Polycyclic Aromatic Hydrocarbons (PAHs) and emerging compounds such as pharmaceuticals and antibiotics are frequently found in rivers flowing through big cities. This work evaluated the presence of fifteen priority PAHs, eight pharmaceuticals including the antibiotics ciprofloxacin (CIP) and sulfamethoxazole (SMX), together with their main antibiotic resistant genes (ARGs) and the structure of the natural bacterioplankton community, in an urbanized stretch of the river Danube. SMX and diclofenac were the most abundant chemicals found (up to 20 ng/L). ARGs were also found to be detected as ubiquitous contaminants. A principal component analysis of the overall microbiological and chemical data revealed which contaminants were correlated with the presence of certain bacterial groups. The highest concentrations of naphthalene were associated with Deltaproteobacteria and intI1 gene. Overall, the most contaminated site was inside the city and located immediately downstream of a wastewater treatment plant. However, both the sampling points before the river reached the city and in its southern suburban area were still affected by emerging and legacy contamination. The diffuse presence of antibiotics and ARGs causes particular concern because the river water is used for drinking purposes. Full article

Molluscum contagiosum (MC) and warts are common viral infections of the skin. Data regarding the prevalence of MC and verruca in swimmers are very poor and lacking in the literature. The purpose of this study was to determine the incidence of Molluscum Contagiosum (MC) and warts cases among young competitive swimmers participating in Greek swimming clubs. Of 244 swimmers enrolled in this study, 12.3% reported MC and 43% warts, during their swimming career, diagnosed and treated by dermatologists. There was no difference between sexes for MC but diagnoses of warts were higher in females. Axillae and trunk were the most common sites of primary infection for MC but warts mainly appeared on the soles. The incidence of MC and warts in swimmers who use outdoor facilities was higher. In our study, the incidence of warts and MC in Greek swimmers is considered high. Moist walking surfaces, placing towels on locker room benches, and sharing equipment are behaviors that cause infections. An early diagnosis of warts and MC lesions must be implemented in every swimmer through dermatological examination. Taking proper measures for reducing the risk of warts and MC transmission in Greek swimmers is mandatory. Full article

This paper deals with the question of unobservable heterogeneity and problems of scale in urban water demand. For this purpose, the determinants of domestic water consumption and the elasticities were estimated using a hierarchical model. For our empirical analysis, a household level data panel from Valencia (Spain) between 2009 and 2011 was available. Households were assigned to the city neighbourhoods to which they belong, which allowed us to incorporate the intra-urban scale into the analysis. In the estimate, the average price paid by each household in each bimonthly period was used due to the current tariff structure in Valencia. Regarding our results, there were differences in the consumption between the different neighbourhoods that were not independent of the average price paid by households. We found that 27% of the variability in consumption was explained by differences in household behaviour. In addition, an average price-elasticity in Valencia for all periods of −1.868 was obtained as well as a range of elasticities for the different neighbourhoods between (−1.53 and −1.21). From the results obtained, it is possible to extract relevant information for local water managers in order to apply economic instruments, prices and taxes to urban water demand. Full article

Despite growing recognition of solutions to water scarcity challenges, decision-makers across the world continue to face barriers to effective implementation of water planning, governance and management. This is evident in the cases of Lahore and Karachi in the Indus Basin in Pakistan and illustrated through the experiences of the provincial government departments and utilities. Water scarcity and associated challenges are continuing to impose significant costs on these cities, which continue to grow as water availability further declines, demand increases, water quality deteriorates, and infrastructure degrades. A team of Australian water experts was commissioned by the Australian Water Partnership to diagnose urban water challenges and identify priority actions for improved water security, in collaboration with Pakistani partners. This paper presents the outcomes of that work. This includes a synthesis of the published literature and data on the geographical, climatic, and water scarcity contexts of both Karachi and Lahore. It then identifies responses to water insecurity that have been considered or implemented in the past and the barriers that have inhibited the effectiveness of these efforts. Finally, it presents actions within five priority action areas that Pakistani stakeholders have identified as being most practical and impactful for improving water security outcomes. Full article

Filters are popularly used in municipal wastewater treatment plants (WWTPs) as the final guards against effluent solids; however, their impacts on antibiotic resistance gene (ARG) removal in the WWTPs are still unclear. In this study, metagenomic analysis was used to find out the distribution characteristics of ARGs in two WWTPs equipped with the same D-Type fiber filters. Samples of influent, activated sludge liquor, secondary clarifier effluent, and D-Type filter effluent were found to host 695, 609, 675, and 643 ARG subtypes, respectively. The detected ARGs mainly included macB (4.1–8.9%), sav1866 (1.7–3.4%), and oleC (1.6–3.8%). Co-occurrence network analysis combined with contribution analysis helped to identify the ARG-related risks in the samples. Microbacterium, Acinetobacter, Gordonia, and Streptomyces significantly correlated with more than ten kinds of ARG subtypes, implying that they are potential hosts for these resistance gene subtypes. The number of ARG subtypes in the D-Type filter was less than those in the secondary clarifier effluent, indicating the potential of D-Type filters to effectively reduce the ARGs released into the environment. However, the abundance of two pathogens, Mycobacterium and PmrA, increased after the treatment by the D-Type filter, which may reveal the adverse effects of intercepting ARGs inside the fibers. The results may help the understanding of the complex role of the D-Type fiber filter on ARG distribution in WWTPs. Full article

The interaction of waves and ice is of significant relevance for engineers, oceanographers and climate scientists. In-situ measurements are costly and bear uncertainties due to unknown boundary conditions. Therefore, physical laboratory experiments in ice tanks are an important alternative to validate theories or investigate particular effects of interest. Ice tanks use model ice which has down-scaled sea ice properties. This model ice in ice tanks holds disadvantages due to its low stiffness and non-linear behavior which is not in scale to sea ice, but is of particular relevance in wave-ice interactions. With decreasing stiffness steeper waves are required to reach critical stresses for ice breaking, while the non-linear, respectively non-elastic, deformation behavior is associated with high wave damping. Both are scale effects and do not allow the direct transfer of model scale test results to scenarios with sea ice. Therefore, the alternative modeling approach of Model Ice of Virtual Equivalent Thickness (MIVET) is introduced. Its performance is tested in physical experiments and compared to conventional model ice. The results show that the excessive damping of conventional model ice can be reduced successfully, while the scaling of the wave induced ice break-up still requires research and testing. In conclusion, the results obtained are considered a proof of concept of MIVET for wave-ice interaction problems. Full article

This study evaluated the efficiency of two biofilter systems, with and without biochar chambers installed, at degrading and removing HCH and its isomers in natural drainage water. The biochar biofilter proved to be 96% efficient at cleaning HCH and its transformation products from drainage water, a significant improvement over classic biofilter that remove, on average, 68% of HCH. Although iron- and sulfur-oxidizing bacteria, such as Gallionella and Sulfuricurvum, were dominant in the biochar bed outflows, they were absent in sediments, which were rich in Simplicispira, Rhodoluna, Rhodoferax, and Flavobacterium. The presence of functional genes involved in the biodegradation of HCH isomers and their byproducts was confirmed in both systems. The high effectiveness of the biochar biofilter displayed in this study should further encourage the use of biochar in water treatment solutions, e.g., for temporary water purification installations during the construction of other long-term wastewater treatment technologies, or even as final solutions at contaminated sites. Full article

Water policy-making requires the dedicated involvement of all stakeholders, but difficulties remain for the community sector. This study aims to examine the critical challenges of community involvement in water policy decision-making in Thailand. Both qualitative and quantitative methods used in this research project consisted of 39 interviews with informants from a variety of interested parties and 403 community members from around the East Coast River Basin in Thailand completing a survey questionnaire. The results have shown that although mechanisms to enable community involvement in decision-making, such as public consultation and water-related committees, exist, problems remain within the community sector. The critical challenges lie in the opportunities of being consulted and the sharing of power in water policy-making. Although the networks are important, at the same time, they are also obstructing the community sectors in linking their requirements to a final decision, as well as dealing with politics, policy-makers, and staff who organized the process. Therefore, the government should further develop water committee mechanisms by setting up a comprehensive yet practically easy consultation process so that new or inexperienced community members get an opportunity to practice and learn the vital elements necessary in water policy-making. Further research should be conducted in order to compare the opportunities in water decision-making between communities in rural and urban areas. Studies at the local government level should be carried out, with results used as a mechanism to enable community involvement at higher levels of water policy decision-making. Full article