Water Cycle Management Research Articles

Aitsu Marine Station, Center for Water Cycle, Marine Environment and Disaster Management (CWMD), Kumamoto University

Aitsu Marine Station, Center for Water Cycle, Marine Environment and Disaster Management (CWMD), Kumamoto University

Co-developing evidence-informed adaptation actions for resilient citywide sanitation: Local government response to climate change in Indonesia

Already climate-related hazards are impacting sanitation systems in Indonesia and elsewhere, and climate models indicate these hazards are likely to increase in frequency and intensity. Without due attention, to maintain existing progress on Sustainable Development Goal 6’s target 6.2 and to increase it to meet ambitions for 2030 will be difficult. City governments need new forms of evidence to respond, as well as approaches to enable them to consider sufficient breadth of strategies to adapt effectively. This paper describes a co-production research process which engaged local governments in four cities in Indonesia experiencing different climate hazards. Local government engagement took place across three stages of (i) inception and design, (ii) participation as key informants and (iii) joint analysis and engagement on the findings. We adapted and simplified a risk prioritisation process based on current literature and employed a novel framework of a ‘climate resilient sanitation system’ to prompt articulation of current and proposed climate change adaptation response actions. In contrast to many current framings of climate resilience in sanitation that focus narrowly on technical responses, the results paint a rich picture of efforts needed by city governments across all domains, including planning, institutions, financing, infrastructure and management options, user awareness, water cycle management and monitoring and evaluation. Local government commitment and improved comprehension on the implications of climate change for sanitation service delivery were key outcomes arising from the co-production process. With strengthened policy and capacity building initiatives from national level, this foundation can be supported, and Indonesian city governments will be equipped to move forward with adaptation actions that protect on-going access to sanitation services, public health and the environment.

Measuring operational and quality-adjusted efficiency of Chilean water companies

The path to a sustainable management of the urban water cycle requires the assessment of both operational and quality-adjusted efficiency in a unified manner. This can be done by the use of non-radial Data Envelopment Analysis models. This study used Range Adjusted Measure models to evaluate the operational, quality-adjusted, and operational & quality-adjusted efficiency (O&QAE) scores of the Chilean water industry including water leakage and unplanned interruptions as undesirable outputs. It was found that on average water utilities presented large O&QAE scores over time. The mean O&QAE score was 0.964 which means that water utilities could further reduce costs and undesirable outputs by 3.6% on average, while trying to expand the scale of operation. This finding suggests that excellent quality-adjusted efficiency at an efficient expenditure could be feasible. It was also evidenced that customer density, mixed water resources, and ownership influenced the O&QAE of Chilean water companies.

Analysis of Kenya’s Atmospheric Moisture Sources and Sinks

Abstract Achievement of the United Nations Sustainable Development Goals (SDGs) is contingent on understanding the potential interactions among human and natural systems. In Kenya, the goal of conserving and expanding forest cover to achieve SDG 15 “Life on Land” may be related to other SDGs because it plays a role in regulating some aspects of Kenyan precipitation. We present a 40-yr analysis of the sources of precipitation in Kenya and the fate of the evaporation that arises from within Kenya. Using MERRA-2 climate reanalysis and the Water Accounting Model 2 layers, we examine the annual and seasonal changes in moisture sources and sinks. We find that most of Kenya’s precipitation originates as oceanic evaporation but that 10% of its precipitation originates as evaporation within Kenya. This internal recycling is concentrated in the mountainous and forested Kenyan highlands, with some locations recycling more than 15% of evaporation to Kenyan precipitation. We also find that 75% of Kenyan evaporation falls as precipitation elsewhere over land, including 10% in Kenya, 25% in the Democratic Republic of the Congo, and around 5% falling in Tanzania and Uganda. Further, we find a positive relationship between increasing rates of moisture recycling and fractional forest cover within Kenya. By beginning to understand both the seasonal and biophysical interactions taking place, we may begin to understand the types of leverage points that exist for integrated atmospheric water cycle management. These findings have broader implications for disentangling environmental management and conservation and have relevance for large-scale discussions about sustainable development.

Circular economy and payment for ecosystem services: A framework proposal based on water reuse

Water scarcity forces the use of non-conventional water sources, to satisfy water demand, such as the effluent of wastewater treatment plants (WWTPs). Water reuse helps to close the urban water cycle and reduce pressure on available water resources, providing a bases for circular economy in the water sector. Under an ecosystem services (ES) point of view, if water reuse is considered the best management option in water scarcity areas, WWTPs are responsible for the ES of provisioning. One of the main requirements for the ES of provisioning is to guarantee the reclaimed water quality due to this water being discharged back into the ecosystem. Hence why removing pollutants, such as pharmaceutical and personal care products (PPCPs), is necessary to reduce the environmental impact of reused water. Considering the lack of legislation about PPCPs in effluents, this study proposes the use of the Payment for Ecosystem Services (PES) approach as an innovative solution to provide reclaimed water without PPCPs considering both the environmental and institutional context and the importance of WWTPs as non-conventional water sources. This study contributes to consider the PES as a water cycle management tool and its suitability to be used to remove PPCPs is highlighted, with the purpose of promoting water reuse in water scarcity areas under circular economy approach.

Full-Scale Odor Abatement Technologies in Wastewater Treatment Plants (WWTPs): A Review

The release of air pollutants from the operation of wastewater treatment plants (WWTPs) is often a cause of odor annoyance for the people living in the surrounding area. Odors have been indeed recently classified as atmospheric pollutants and are the main cause of complaints to local authorities. In this context, the implementation of effective treatment solutions is of key importance for urban water cycle management. This work presents a critical review of the state of the art of odor treatment technologies (OTTs) applied in full-scale WWTPs to address this issue. An overview of these technologies is given by discussing their strengths and weaknesses. A sensitivity analysis is presented, by considering land requirements, operational parameters and efficiencies, based on data of full-scale applications. The investment and operating costs have been reviewed with reference to the different OTTs. Biofilters and biotrickling filters represent the two most applied technologies for odor abatement at full-scale plants, due to lower costs and high removal efficiencies. An analysis of the odors emitted by the different wastewater treatment units is reported, with the aim of identifying the principal odor sources. Innovative and sustainable technologies are also presented and discussed, evaluating their potential for full-scale applicability.

IMPACT OF INTENTION TO USE REUSED WASTEWATER FOR COMMUNITY SATISFACTION IN VIETNAM

The paper aims to evaluate factors according to the planned behavioral theory of the community’s intentional attitude towards wastewater reuse. A huge amount of domestic wastewater will deplete water resources if not treated and reused. The survey results from more than 1000 households in the three major cities of Vietnam (Hanoi, Ho Chi Minh, and Da Nang) show that the community’s intention is good and all have a positive impact on the people’s satisfaction and water cycle management performance. All five factors: emotion, fairness, health risk, subjective norm, trust, have a positive impact on intention to use reused wastewater. Different from other studies, this research assesses the impact of intention to reuse wastewater on community satisfaction. Previous research showed that health risk negatively influenced intention; this study showed that health risk positively influenced intention and community satisfaction.

Assessing socio-economic value of innovative materials recovery solutions validated in existing wastewater treatment plants

Cost benefit analysis (CBA) and social impact assessment are well established methodologies to systematically estimate the viability of investments on technologies as well as the benefits for the society. However, there is a limited application of these assessment methods in the wastewater sector especially for resource recovery to deliver circularity objectives within urban water cycle management. In this regard, the Horizon 2020 SMART-Plant Innovation Action aimed to evaluate holistic impacts of wastewater-based resource recovery by applying and adapting cost benefit and social analysis on innovative technologies (SMARTechs). The SMARTechs were implemented and validated in real wastewater treatment plants (WWTPs) across Europe and Mediterranean basin where potential impacts in terms of carbon, material and energy efficiency, recovery and safe reuse were defined. Sixteen bottom-up SMARTech scenarios were analysed for the estimation of technical, economic and social impacts using CBA, social life cycle assessment (S-LCA) and social readiness level (SRL) methods. Overall, the SMARTechs created benefits both from an environmental and social point of view, with a maximum relative total economic value up to +23% compared to baseline scenario (without any SMARTech implementation). In terms of social benefits, the S-LCA highlighted a global positive impact of all the SMARTechs in terms of technical characteristics and social acceptance. Specifically, SMARTech 1 (cellulose recovery) was the most socially accepted solution thanks to its high performance and simplicity. Finally, based on the SRL assessment, most of the SMARTechs were positioned within the SRL range of 6–7, which implies a good societal acceptance and adaptation potential.

Occurrence and Human Health Risk Assessment of Pharmaceuticals and Hormones in Drinking Water Sources in the Metropolitan Area of Turin in Italy.

Pharmaceuticals and hormones (PhACs) enter the aquatic environment in multiple ways, posing potential adverse effects on non-target organisms. They have been widely detected in drinking water sources, challenging water companies to reassure good quality drinking water. The aim of this study was to evaluate the concentration of sixteen PhACs in both raw and treated drinking water sources in the Metropolitan Area of Turin—where Società Metropolitana Acque Torino (SMAT) is the company in charge of the water cycle management—and evaluate the potential human health risks associated to these compounds. Multivariate spatial statistical analysis techniques were used in order to characterize the areas at higher risk of pollution, taking into account the already existing SMAT sampling points’ network. Health risks were assessed considering average detected concentrations and provisional guideline values for individual compounds as well as their combined mixture. As reported in the just-issued Drinking Water Directive 2020/2184/UE, in order to establish priority substances, a risk assessment of contaminants present in raw drinking water sources is required for monitoring, identifying potential health risks and, if necessary, managing their removal. The results showed negligibly low human health risks in both raw water sources and treated water.

Indicators of climate change impacts on the water cycle and water management

Managing water is a top social and economic responsibility and is expected to become even more critical as climate change, in addition to other human activities, alters water availability and quality. Robust indicators reflecting the effects of climate change on the US and global water cycles are needed in order to appropriately manage water resources. Here, we describe a suite of seventeen water cycle and management indicators, which are based on synthesis of available datasets. These indicators include average and heavy precipitation, standardized precipitation index, annual, 7-day low and 3-day high streamflow volume, streamflow timing, snow cover, snow water equivalent, groundwater level, lake water temperature, stream water temperature, dissolved oxygen, salinity, Palmer Drought Severity Index, water withdrawals, and water use. We also identify three indicators that could be included in the suite of water cycle and management indicators with some additional, directed work: snowfall, evapotranspiration, and soil moisture. Our conceptual framework focuses on known water cycle changes in addition to potential effects on management and addresses water quantity and quality, as well as water use and related interactions with freshwater ecosystems, societal impacts, and management. Water cycle indicators are organized into three categories: (1) hydrologic processes, (2) water quality processes, and (3) water quality and quantity impacts. Indicators described here are recommended to serve as critical references for periodic climate assessments. As such, these indicators support analyses of the effects of global change on the natural environment, agriculture, energy, and water resources, among other sectors. Additionally, we identify research gaps and needs that can be addressed to advance the development of future indicators.

Optimization of Progressive Freezing on Synthetic Produced Water by Circular Moving Cylindrical Crystallizer via Response Surface Methodology

Treatment and disposal are two main approaches for water cycle management in the oil and gas industry. Freeze concentration has been identified as one of the methods to separate water from wastewater samples. The conventional method used for solution movement in progressive freezing technique is stirring by a stirrer. However, the stirrer requires frequent maintenance as it needs to be cleaned and requires longer cleaning time due to the complex structure of a stirrer. Thus, the new solution movement for progressive freezing is proposed, which is circular moving progressive freezing. This study aims to remove water from the wastewater sample (i.e., produced water). To optimize and investigate the effect of coolant temperature, freezing time and rotation speed, response surface methodology (RSM) was applied to determine the efficiency of the process and central composite design (CCD) was used to design the experiment. From the results, the optimum parameters were determined at the freezing time of 22.79 min, coolant temperature of −14.89 °C and rotation speed of 59 rpm. To evaluate the accuracy of the optimization process, a validation experiment was performed and water removal value of 89.67% was achieved.

Water wise – a digital water solution for smart cities and water management entities

Abstract Efficient water management of the urban water cycle is one of the current concerns with the increase of (peri) urban areas due to the population growth, economic development, and possibility of water scarcity due to climate change. To face the increase of the water demand it is imperative the creation of digital water solutions to provide a real-time monitoring, decision support system, to manage the water supply network efficiently and optimize the water-energy nexus. This paper presents a Water Wise System – W2S, results from a R&D project supported by an EU and Portuguese Government Grant. The paper provides a preliminary study of an architecture solution to Water Wise System software, focuses on the water challenges, present technology, digital water, IoT and the future of smart cities. The solution aims to support a paradigm shift in the management of water distribution networks, with predictive and analytical convergence supported in Machine Learning, Deep Learning and an integration with SCADA, GIS and EPANET.

Urban water supply automation – today and tomorrow

AbstractAutomation is a collection of a whole set of theories and methods to make a system work automatically as intended, in our case the urban water supply system. A critical feature of automation is the feedback principle: a sensor is measuring a certain variable, e.g. a concentration; a computer tests that the measurement is valid; a computer algorithm calculates and decides what should be corrected; a pump or valve or some other device transforms the decision to action. All of this is untouched by human hand. The ‘intention’, or the goal, must be provided to the controller. The key component of automation is the system that can represent any component or process in the water supply system and even the complete system. Automation technology always must be combined with a true understanding of people at all levels. Otherwise, there is a high risk for misunderstandings and failures. Three categories of problems are highlighted, where automation can contribute: uncertainty, feedback, and complexity. A key challenge is the handling of disturbances. Integrated management of the whole urban water cycle will be required in future urban areas to acquire sustainable operations. Automation is a crucial condition to make integration possible in complex systems.

Investigative monitoring of pesticide and nitrogen pollution sources in a complex multi-stressed catchment: The lower Llobregat River basin case study (Barcelona, Spain)

The management of the anthropogenic water cycle must ensure the preservation of the quality and quantity of water resources and their careful allocation to the different uses. Protection of water resources requires the control of pollution sources that may deteriorate them. This is a challenging task in multi-stressed catchments. This work presents an approach that combines pesticide occurrence patterns and stable isotope analyses of nitrogen (δ15N-NO3−, δ15N-NH4+), oxygen (δ18O-NO3−), and boron (δ11B) to discriminate the origin of pesticides and nitrogen-pollution to tackle this challenge. The approach has been applied to a Mediterranean sub-catchment subject to a variety of natural and anthropogenic pressures. Combining the results from both analytical approaches in selected locations of the basin, the urban/industrial activity was identified as the main pressure on the quality of the surface water resources, and to a large extent also on the groundwater resources, although agriculture may play also an important role, mainly in terms of nitrate and ammonium pollution. Total pesticide concentrations in surface waters were one order of magnitude higher than in groundwaters and believed to originate mainly from soil and/or sediments desorption processes and urban and industrial use, as they were mainly associated with treated wastewaters. These findings were supported by the stable isotope results that pointed to an organic origin of nitrate in surface waters and most groundwater samples. Ammonium pollution observed in some aquifer locations is probably generated by nitrate reduction. Overall, no significant attenuation processes could be inferred for nitrate pollution. The approach presented here exemplifies the investigative monitoring envisioned in the Water Framework Directive.

Environmental analysis of servicing centralised and decentralised wastewater treatment for population living in neighbourhoods

The planning and construction of large-scale wastewater infrastructure, such as sewerage networks and wastewater treatment plants, is undertaken by the public sector or by publicly regulated monopolies. Only on smaller scales can infrastructure be managed by private companies or through local collective initiatives. Within this framework of water cycle management, there is an increasing movement of the population towards cities where economic activity is concentrated. This scenario is particularly pronounced in certain regions of the world and makes it necessary to rethink whether decentralised treatment offers a way of ensuring the servicing of wastewater treatment in new urban developments, alleviating pressure on facilities that are at the limit of their capacity.In this study four systems were evaluated: two centralised and two decentralised configurations, from an environmental and economic perspective, posing as working hypothesis how different wastewater treatment schemes influence the carbon footprint of the population living in a neighbourhood. The analysis of the results identifies that the decentralised systems present a reduction in the carbon footprint of residents of around 20–23 % depending on the technology considered. In addition, reclaimed water can meet the water quality requirements for irrigation of the green areas in the neighbourhood. Although decentralised systems have higher construction costs, they can be amortised due to lower energy consumption, so the payback time is estimated to be 8–9 years, lower than that of centralised systems. Considering the problems associated with changing and replacing existing networks, decentralised wastewater treatment systems is especially recommended for new dwelling developments, based on its environmental and economic indicators.

An Integrative Information Aqueduct to Close the Gaps between Satellite Observation of Water Cycle and Local Sustainable Management of Water Resources

The past decades have seen rapid advancements in space-based monitoring of essential water cycle variables, providing products related to precipitation, evapotranspiration, and soil moisture, often at tens of kilometer scales. Whilst these data effectively characterize water cycle variability at regional to global scales, they are less suitable for sustainable management of local water resources, which needs detailed information to represent the spatial heterogeneity of soil and vegetation. The following questions are critical to effectively exploit information from remotely sensed and in situ Earth observations (EOs): How to downscale the global water cycle products to the local scale using multiple sources and scales of EO data? How to explore and apply the downscaled information at the management level for a better understanding of soil-water-vegetation-energy processes? How can such fine-scale information be used to improve the management of soil and water resources? An integrative information flow (i.e., iAqueduct theoretical framework) is developed to close the gaps between satellite water cycle products and local information necessary for sustainable management of water resources. The integrated iAqueduct framework aims to address the abovementioned scientific questions by combining medium-resolution (10 m–1 km) Copernicus satellite data with high-resolution (cm) unmanned aerial system (UAS) data, in situ observations, analytical- and physical-based models, as well as big-data analytics with machine learning algorithms. This paper provides a general overview of the iAqueduct theoretical framework and introduces some preliminary results.

Urban water works and water cycle management: advanced approaches

Urban water works and water cycle management: advanced approaches

Evaluation on the integrated water resources management in China’s major cities -- Based on City Blueprint® Approach

Though with abundant water resources in China, unevenly geographical and temporal distribution of water resources have constantly resulted in many severe water issues in various cities, such as inundation, drought, urban flooding, water shortage, water pollution, and inaccessibility of safe drinking water, in addition to the negative impacts of climate change. Intensive industrialization, fast urbanization, and prompt modernization have aggravated the water conflicts between different stakeholders. Furthermore, nearly 60% of Chinese population is agglomerated in urban area to exacerbate the water stress in cities, especially in megacities. In order to evaluate the performance of the integrated water resources management (IWRM) in major cities in China, and to reveal the key obstacles and challenges to the IWRM in these cities for future improvement, the modified City Blueprint® Approach, in combining with the hierarchical cluster analysis (HCA), were applied to examine the efficiency, effectiveness, and capability of the IWRM in 32 selected major cities in China, including 4 municipalities directly under the Central Government, 27 provincial capitals, and Shenzhen (a fast-emerging city located on the Pearl River Delta). The City Blueprint® Approach, consisting of three complementary frameworks, is a systematic analytic and diagnostic tool to assess the major challenges to cities (Trends and Pressures Framework, TPF), to appraise the management of urban water cycle (City Blueprint Framework, CBF), and to identify the paths of water governance improvement (Governance Capacity Framework, GCF). Significant differences have been observed between various districts and different cities. For TPF, in general, environmental pressures increase as the city scale expands, where river peak discharges and urban drainage flood are two common environmental challenges encountered by all cities. Social pressures decline and the financial pressures slightly decrease as city scale enlarged, where economic pressure and education rate are dominant indicators within each city category, respectively. For CBF, all cities have realized a great achievement in providing good basic water services, in addition to excellent performance of five indicators, drinking water quality, access to drinking water, access to sanitation, wastewater treatment, and management and action plans. In contrast, nutrient and energy recovery, public participation, and solid waste recycling, are the most critical issues to be resolved by all cities. For GCF, higher score in Enabling symbolizes the good performance of governance capacity to result in well management and action plans. Unfortunately, low score in Knowing, especially in the condition of useful knowledge, has caused the poor performance of public participation. Through HCA, the similarities and disparities between cities within diverse city categories were also revealed. In order to enhance the IWRM in major cities in China, various recommendations for future improvement were then provided, accordingly.

Evaluation of water quality state through regulations and physicochemical indicators for the administration of water resources in the Integrated Management District of Salto del Tequendama

Water resources are of great importance in the administration of protected areas. This is linked to the quality of surface water bodies that pro-vide different eco-systemic services, since they shelter different species of fauna and flora. In relation to Resolution 1596 of 2006 adopted by the General Direction of the CAR, which states the Management Plan for the Integrated Management District (DMI by its abbreviation in Spanish) in the area of Salto del Tequendama - Cerro Manjui, attached to the Water Cycle Management program and in relation with the "Water Quality Control" project, states the evaluation of the conditions of the different water sources in relation to water collection given by the communities as one of its objectives, and at the same time exposes the determinants of the conditions that take place in the surface water bodies. In this article, a correlation of the uses that are stated in the management plan will be performed in order to com-pare the results, which are obtained by means of the environmental monitoring that is evaluating the control and management of the "Water Quality Control". Based on the evaluation of water quality, it was possible to determine whether the uses that are defined in the Management Plan are appropriate, by linking them to the Water Quality Control program. Calculations were also made conducive to obtain indicators that would allow us to estimate the quality of the water and possible sources of pollution.

Variations in terrestrial water storage in the Lancang-Mekong river basin from GRACE solutions and land surface model

Measurement of regional water resource variations is significant for understanding water cycle and water management. This is especially true for transboundary river basins. This study investigated the terrestrial water storage dynamics of the Lancang-Mekong River basin, which has a total area of 795,000 km2 and distributed between six countries in Southeast Asia, based on the terrestrial water storage anomalies (TWSA) from the Gravity Recovery and Climate Experiment (GRACE) satellites and the Global Land Data Assimilation System (GLDAS) model. A spatial weighted centroid analysis concept from geographical information science was introduced to track the movement of terrestrial water storage centroid of the basin. And the response of terrestrial water storage dynamics to climate variations throughout the basin was examined by quantifying the correlations of TWSA with a multi-scalar drought index. Results show that during 2003 to 2016, the upstream basin (Lancang River basin) experienced slight decreasing trends (ranging from −2.45 to 0 km3/yr revealed by five different GRACE solutions), and the downstream basin (Mekong River basin) generally did not express statistically significant trends; five GRACE solutions are more consistent in the downstream basin than the upstream basin, and the mascons-based TWSA processed at Jet Propulsion Laboratory (JPL) produced quite different results with the other four solutions. Generally, there are good correlations between GRACE observations and GLDAS model. The TWSA is 1–2 month lagged correlated with precipitation, evapotranspiration, and runoff anomalies, because water from precipitation may take a long period to loss from evapotranspiration and infiltrate into the soil. In general, water storage dynamics are closely correlated with climatic dry and wet conditions at middle-long periods (6–12 months) in the basin, and the correlation coefficients in wet season are generally higher than those in dry season. However, a different pattern was found since 2010: in the 2010–2016 period, correlations between TWSA and the multi-scalar drought index in Lancang River basin reduced relative to the 2003–2009 period but became stronger in Mekong River basin after 2009. The results of this study highlight the differentiation of water storage dynamics’ response to the climate variation between upstream and downstream of Lancang-Mekong basin in the period 2010–2016 and the possibility of examining basin storage disturbed by human activities in the basin.