Search Results (24)

The implementation of a decentralized blue–green infrastructure (BGI) is a key strategy in climate adaptation and stormwater management. However, the integration of urban trees into the multifunctional infrastructure remains insufficiently addressed, particularly regarding rooting space in dense urban environments. Addressing this gap, the BoRSiS project developed the soil-pipe system (SPS), which repurposes the existing underground pipe trenches and roadway space to provide trees with significantly larger root zones without competing for additional urban space. This enhances tree-related ecosystem services, such as cooling, air purification, and runoff reduction. The SPS serves as a stormwater retention system by capturing excess rainwater during heavy precipitation events of up to 180 min, reducing the pressure on drainage systems. System evaluations show that, on average, each SPS module (20 m trench length) can store 1028–1285 L of water, enabling a moisture supply to trees for 3.4 to 25.7 days depending on the species and site conditions. This capacity allows the system to buffer short-term drought periods, which, according to climate data, recur with frequencies of 9 (7-day) and 2 (14-day) events per year. Geotechnical and economic assessments confirm the system stability and cost-efficiency. These findings position the SPS as a scalable, multifunctional solution for urban climate adaptation, tree vitality, and a resilient infrastructure. Full article

This study assessed the status of water, sanitation, and hygiene (WASH) services at (49) selected primary schools in uMfolozi Local Municipality, which is situated in the province of Kwa-Zulu Natal in South Africa. Data were collected using an observational checklist tool and by conducting a walk-through survey to inspect the conditions of sanitary facilities, observe the hand-washing practices of the school learners, and analyse the accessibility to safe drinking water in school premises. The data were analysed with the Statistical Package for Social Science Version 29. This study revealed that there is easy access to safe drinking water in all but one school. The dependability of the water supply seemed to be one of the most urgent problems in every school, even though all of them have some kind of drinking water infrastructure on their grounds. Municipal water (n = 25, 36%) and rainwater (n = 25, 36%) were the most common type of water used in schools compared to borehole (n = 15, 22%) and tanker truck water (n = 4, 6%). Schools must have a reserved water supply because of the inconsistent supply of municipal water, and because rainwater is a seasonal harvest while borehole water may be affected by factors like load-shedding. The UNICEF-described ratio of one tap or disperser per fifty learners suggests that the water taps in the schoolyard were insufficient in some schools (n = 25, 36%). Rainwater is collected through a gutter system in the school building roofs and stored in 5000–10,000 Jojo tanks. Borehole water is pumped into Jojo tanks at an elevated position where it is stored, and learners receive the water through taps connected to the borehole tanks. During an emergency when there is no water supply from other sources, tanker trucks are hired to fill tanks that are also used to store rainwater. The borehole and rainwater quality appeared to be clear, but water treatment had not been performed, and the microbial quality was unknown. This shows that the Sustainable Development Goal (SGD) 6, clean water and sanitation, is still far from being met. According to national norms and standards for domestic water and sanitation services, people who do not use water treatment or purification techniques fall in the ‘no service’ category and contribute to the water backlog. Pit latrines (n = 46, 94%) and flush toilet (n = 3, 6%) were found to be the only convenient toilet systems used. The number of toilets is not sufficient according to the guidelines. There are (n = 46, 94%) of the schools in the study area using pit latrine due to insufficient or no water supply. In 89.8% of primary schools, sanitation facilities are in working condition in terms of repair and hygiene, while 10.2% are not usable in terms of hygiene, and these are mostly boy’s toilets. All schools (n = 46, 94%) that have flush toilets is because they received sponsorship from non-government stakeholders that funded them in achieving piped water systems that permit the functionality of flush toilets. For the purposes of this study, hygiene was evaluate based on the items found in toilets and handwashing practices. The hygiene aspects of toilets included tissues, cleanness, and toilet seat. For handwashing practices we looked the number of washing basins, the colour of water, and having soaps to use. In the schools that did provide handwashing facilities, some of the toilets were broken, there was no water, or there was no drainage system in place to allow them to function. However, according to the school act, the handwash basins should be inside the facilities. A total of (n = 7, 14%) of handwash basins were inside the toilets. Only (n = 2, 4%) of schools had handwashing facilities which were Jojo tanks with taps near toilets, which were outside of the toilet, with no soap provided. Additionally, (n = 40, 82%) of learners used drinking points for handwashing, which can possibly transmit microbes among them. The findings revealed that, in general, (n = 32, 64%) of school toilets were clean, while, in general, the girls’ toilets were cleaner than the boys’ toilets. In all the schools, the cleaning services were from the people who were involved in school nutrition. In conclusion, there were water sources available for access to water inside schools; however, the situation can be improved by increasing the number of water source points. Pit latrines were the main used toilets, which were in a majority of the schools, and did not have the necessary terms for hygiene such as handwashing basin, tissues, and others. The lack of the main aspect, i.e., access to water and sanitation items, results in an impact on hygiene to learners as they will fail to practice proper hygiene. However, improvement can still be made by keeping the boys’ toilets clean while increasing the number of handwashing basins inside the toilets, so that they do not use taps outside the toilets. Schools should work towards meeting the required number of handwashing basins to increase access to handwashing facilities. Full article

This study investigated the purification of pollutants in runoff rainwater by constructing a micro-ecosystem using waste-activated sludge (WAS) and riverbed sludge (RBS) as inoculums in combination with pervious concrete. The research results showed that the best hydraulic retention time (HRT) was 9 h. The COD and ammonia nitrogen (NH₄⁺-N) removal of the waste-activated sludge ecosystem (WASE) was 62.67% and 71.21%, respectively, while the riverbed sludge ecosystem (RBSE) showed COD and NH₄⁺-N removal percentages of 46.05% and 66.55%, respectively. The analysis of the genetic metabolism of microbial genes showed that the system was microbially enhanced with extensive and diverse populations. At the phylum level, the microorganisms responsible for degrading organic matter were mainly Firmicutes and Actinobacteriota. At the genus level, the Trichococcus genus was dominant in the WASE, while the Dietzia, norank_f__Sporomusaceae and norank_f__norank_o__norank_c__BRH-c20a genera were the central bacterial populations in the RBSE. The proliferation of phylum-level bacteria in the WASE was relatively large, and the genus-level bacteria demonstrated a better removal efficiency for pollutants. The overall removal effect of the WASE was better than that of the RBSE. The application analyses showed that a WASE is capable of effectively accepting and treating all rainfall below rainstorm levels and at near-full rainstorm levels under optimal removal efficiency conditions. This study innovatively used wastewater plant waste-activated sludge combined with pervious concrete to construct a micro-ecosystem to remove runoff rainwater pollutants. The system achieved pollutant removal comparable to that of pervious concrete modified with adsorbent materials. An effective method for the collection and pollutant treatment of urban runoff rainwater is provided. Full article

This study conducted a pilot test and field demonstration to analyze the feasibility of using rainwater for road surface sprinkling and its effectiveness in reducing fine dust to create sustainable cities. The pilot test results verified the effectiveness of rainwater sprinkling on road surfaces in reducing fine dust. Subsequently, to ensure field applicability, a test bed with different pavement sections was established along Ojeong-ro in Bucheon, Gyeonggi-do, and a circulatory system for reusing the runoff rainwater was installed and tested for its acceptable dust reduction effectiveness. The results showed that the section with porous pavement exhibited a significant reduction in acceptable dust levels, and a trend of decreasing pollutant levels due to the initial washing effect of rainwater was observed. However, the water quality and quantity analysis revealed that additional purification processes are necessary to reuse the water for road surface sprinkling. Based on these findings, this study suggests that expanding porous pavement and introducing purification systems are essential for installing rainwater utilization facilities to reduce fine dust in urban areas. This research provides critical foundational data that can contribute to urban environmental improvement and establish a sustainable water circulation system. Full article

Water ecological problems involve flood, drought, water pollution, destruction of water habitat and the tense relationship between humans and water. Water ecological problems are the main problems in the development of countries all over the world. In terms of ecological protection, China has put forward the ecological red line policy. Water ecology is an important component of the ecosystem, and the delineation of the water ecological red line is an important basis for ecological protection. Based on ecosystem services, this paper tries to determine the red line of the water ecology space and tries to solve various water problems comprehensively. Based on the ecosystem services accounting method, the SWAT (soil and water assessment tool) model was used to simulate the spatial–temporal dynamic quantities of water purification and rainwater infiltration services in the upper reaches of the Hanjiang River. The basin was divided into 106 sub-basins and 1790 HRUs (hydrological response units). Water quality data taken from 8 sites were used to verify the simulation results, and the verification results have high reliability. The grid scale spatialization of water quality and rainwater infiltration is realized based on HRU. The seasonal characteristics of hydrological regulation and control services were analyzed, the red line of hydrological regulation and control in the upper reaches of the Hanjiang River was defined, and the dynamic characteristics of water ecological red line were analyzed. According to the research results, the water ecological protection strategy of the basin is proposed. The prevention and control of water pollution should be emphasized in spring and summer, the prevention and control of rain flood infiltration in autumn and winter, and the normal monitoring and management should be adopted in the regulation and storage. The results of this study can provide scientific reference for water resources management and conservation policy making. Full article

Rainwater and sewage are important pollution sources for surface water bodies. Vertical greening systems (VGSs) are extensively employed for these wastewater treatments due to the green and sustainable characteristics, as well as their high-efficiency in pollutant (organic matter, nitrogen, and phosphorus) removal. At present, more and more VGSs are designed with green buildings, serving city ecosystems. This study provides an overview of different kinds of VGSs for rain and sewage treatment, emphasizing their types, design, mechanisms, selection of plants, and growth substrate. Plants play a crucial role in pollutant removal, and different plants usually obtain different efficiencies of water treatment. Climbing plants and ornamental plants with fast growth rates are priority selections for VGSs, including Canna lilies, Jasmine, Grape vine, Boston ivy, Pittosporum tobira, Pelargonium australe, Mentha aquatica, and Lythrum salicaria. The substrate is the most critical part of the VGS, which plays an important role in regulating water flow, supporting plant growth, promoting biofilm growth, filtering pollutants, and adsorbing nutrients. The single substrate either has a blockage problem or has a short holding time. Therefore, a number of studies have mixed the substrates and integrated the advantages of the substrates to form a complementary effect, thereby improving the overall purification efficiency and stability. Novel substrates (sand, spent coffee grounds, date seeds, coffee grinds, reed-based, etc.) are usually mixed with coco coir, light-weight expanded clay, growstone, or perlite at a certain ratio to obtain optimum treatment performance. Moreover, plants in clay show more significant growth advantages and health statuses than in zeolite or soil. Operating parameters are also significant influences on the treatment performance. This review provides theoretical and technical support for designing sustainable, environmentally friendly, and cost-effective VGSs in treating rainwater and sewage. Full article

Green roof systems are regarded as a viable solution for mitigating urban environmental challenges and offering a multitude of environmental benefits. Currently, green roofs are increasingly being utilized for the management of rainwater runoff and wastewater. The integration of decentralized rainwater and sewage on-site treatment technology with urban green buildings is being gradually promoted. Green roofs can also be considered as a form of decentralized rainwater and sewage on-site technology, which holds great potential for widespread adoption in the future. Several studies have suggested that green roofs may serve as a potential source of pollutants; however, there are also studies that clearly demonstrate the efficient removal of nutrients and organic pollutants by green roofs. This article critically examines the existing literature on water treatment aspects associated with green roofs and elucidates their classification and operational mechanisms. Through an analysis of previous research cases, it becomes evident that both substrate and vegetation play a significant role in influencing the treatment performance of green roofs. By designing and configuring appropriate substrate and vegetation, green roofs can play a pivotal role in the purification of water quality. Finally, a brief outlook is presented for the future research directions of green roofs, with the anticipation that green roofs will feature more innovative and environmentally friendly designs, as well as expanded prospects for application. Full article

Amidst rapid urbanization and escalating environmental degradation in China’s urban areas due to climate change, traditional drainage systems struggle to cope with rainfall, resulting in frequent flood disasters. In response, rain gardens have emerged as ecologically practical stormwater management solutions that integrate urban flood control with landscape design. Leveraging the dual benefits of rainwater purification and aesthetic enhancement provided by vegetation, herbaceous plant-based rain gardens have assumed a pivotal role in green infrastructure. However, dedicated research on the application of herbaceous plants in rain garden design is limited, especially within China’s water-stressed context. This study employs a literature review and case analysis to explore this critical issue. Initially, it delineates the concept of the sponge city introduced by the Chinese government. Subsequently, it reviews concepts and methods of plant biodiversity design in urban settings and rain gardens and elucidates the structure and function of rain gardens. Four Chinese rain gardens in different urban environments (old industrial areas, university campuses, urban villages, and urban highway green belts) were selected to examine the selection and arrangement of herbaceous plants while identifying deficiencies in their designs. Finally, feasibility suggestions are provided for the design of herbaceous plant diversity in Chinese rain gardens. This study’s findings can provide a reference for the planting design of herbaceous plants in rain gardens for other countries and regions with similar climates and environmental conditions. Full article

The aim of this paper was to determine the efficiency of a rainwater treatment installation located near the farm buildings of Roztocze National Park (RNP), Poland. The rainwater treatment system, consisting of two polypropylene filters, one activated carbon filter and a UV lamp, was examined. Samples of raw and treated rainwater were collected once a month from June to December 2023. The study shows that average efficiency of pollutant removal in the analysed rainwater treatment system was not very high and amounted to 38.8% for ammonia, 29.6% for turbidity, 27.9% for NO₂, 19.8% for NO₃, and 6.9% for copper. The low efficiency values can be explained by the low concentration of these parameters in rainwater from the tanks. The efficiency of removing microbiological contaminants was very high and ranged from approximately 98% to 100%. It was shown that the UV lamp ensures very good disinfection of rainwater. The study shows that rainwater treated using filtration and disinfection (UV lamp) can be used for watering the Polish Konik horses living in the park, as well as for washing vehicles, watering green areas, or flushing toilets. The present findings can be used in the design of a new system for managing rainwater that is planned to be built in the RNP’s Animal Breeding Centre, as well as to prepare other rainwater systems, especially in protected areas. Full article

The novelty of the paper is the analysis of the possibilities of reducing the operating costs of a mine water pumping station in an abandoned coal mine. To meet the energy needs of the pumping station and reduce the carbon footprint, “green” energy from a photovoltaic farm was used. Surplus green energy generated during peak production is stored in the form of green hydrogen from the water electrolysis process. Rainwater and process water are still underutilized sources for increasing water resources and reducing water stress in the European Union. The article presents the possibilities of using these waters, after purification, in the production of green hydrogen by electrolysis. The article also presents three variants that ensure the energy self-sufficiency of the proposed concepts of operation of the pumping station. Full article

In this work, issues of water separation and purification are addressed, where, in order to achieve the desired results, it is necessary to use several disciplines such as classical physics, biotechnology, automatic control, automation, and applications of industry 4.0. Further, the need for comprehensive and automated solutions for rainwater treatment in the agricultural sector is addressed. This research focuses on designing and implementing a system adapted to these needs using Siemens technologies. The methodology ranges from the design of the Piping and Instrumentation Diagram (P&ID) to the implementation of the interface, incorporating Siemens technologies for data acquisition, electrical connections, treatment programming, and PID controller design. The results show significant advances in the development of the system, highlighting the effectiveness of automation and the HMI-PLC human–machine interface in process monitoring and control. These findings support the viability of a comprehensive rainwater treatment system for the agricultural sector, with important implications for water efficiency, environmental preservation, and increased productivity in agricultural and livestock activities. The contribution of this work is the relationship between engineering and research focused on industrial processes. The scientific contribution is to obtain the dynamic models and apply two strategies to obtain the gains of the PID controller. The first method is performed through the proposal of a Hurwitz polynomial, and the second is performed through genetic algorithms (GA), where they are implemented in a controller that is commonly used in the industry. The technological part includes the integration of work (schemes, programming, and communications) so that the result is as close to what was expected. Full article

Biological retention facilities are widely used in the construction of new urban infrastructure because of the increasingly serious problems of urban waterlogging and rainwater pollution. At present, a common method to resolve these problems is to improve the treatment performance of these facilities to improve the soil filling layer. How to evaluate the comprehensive benefits of the improved soil filling layer is a problem that cannot be ignored. In this paper, data from seven groups of soil improvement schemes were collected through laboratory tests, and an evaluation method based on AHP-CRITIC was proposed. Firstly, the evaluation indexes of soil improvement in biological retention facilities were determined, and their subjective and objective weights were determined by the AHP method and CRITIC method, respectively, and the comprehensive weights were further calculated. A comprehensive evaluation model was established by the TOPSISI method. Finally, the AHP-CRITIC evaluation model determined that 10% zeolite-amended soil had the best comprehensive evaluation effect, followed by 20% zeolite-amended soil and 10% gravel-amended soil. The results show that the evaluation model can comprehensively assess the benefits of soil improvement in bioretention facilities from the levels of infiltration, purification, and economy and can then select the optimal program for use in actual engineering practice. Full article

The rising importance of utilizing rainwater as a sustainable and viable alternative water source is evident amid increasing urbanization and the mounting global apprehensions about water scarcity. This research aims to develop a comprehensive and sustainable approach to rainwater treatment by effectively utilizing the recently constructed solar panels at the University of Engineering and Technology (UET) in Pakistan. The study’s distinctiveness lies in its comprehensive examination of treatment plant efficiency under various weather conditions in a water-scarce region. The main objective of this work is to maximize the harvested rainwater in order to provide safe drinking water while lessening the carbon footprint of treatment operations. The proposed University of Engineering and Technology water purification process (UETWPP) method involves a sequence of four essential rainwater filtration stages, namely aeration, absorption, sediment filtration, and finally, UV disinfection, all powered by solar energy. Water samples were collected monthly for a year to assess the quality of untreated and treated rainwater, including physical, chemical, and biological parameters. Multivariate analysis techniques were used to assess these parameters, including the Friedman test and principal component analyses. By reducing the initial set of twenty components down to the four most critical ones identified in the untreated water samples, the interrelationships among these components were investigated. The results indicate that the quality of treated water using the UETWPP process was found to be suitable for human consumption, aligning with the local standards as well as those established by the World Health Organization (WHO), highlighting the effectiveness of the process in transforming rainwater into potable water. Ultimately, this pilot project showcases the viability and economic efficiency of the proposed system, rendering it easily implementable in other regions. Full article

In order to explore bacteria resources that are applicable for purification of viaduct rainwater, a carbon-fixing bacteria strain numbered 1C-1 was isolated from the sediment of a viaduct rainwater tank. The strain was identified through morphological characteristics and 16S rDNA sequences. The effects of three main factors (the simulated viaduct rainwater concentration, the carbon source dosage, and the inoculation amount) on the nitrogen and phosphorus removal rate of the strain were tested using simulated viaduct rainwater. Based on this, the nitrogen and phosphorus removal efficiencies for the actual viaduct rainwater were verified. The results showed that the strain belonged to Streptomyces sp. Under different simulated viaduct rainwater concentrations, the strain exhibited relatively high efficiency for nitrogen and phosphorus removal at the original concentration of simulated viaduct rainwater; other conditions remaining unchanged, the purification efficiency was relatively high when the glucose dosage was 800 mg, and the removal rates of ammonia nitrogen (NH₄⁺-N), total nitrogen (TN), and total phosphorus (TP) were 71.48%, 47.86%, and 10.43%, respectively; other conditions remaining unchanged, the purification efficiency was relatively high when the inoculation amount was 1%, and the removal rates of NH₄⁺-N, TN, and TP reached 58.62%, 58.35%, and 27.32%, respectively. Under the above optimal process conditions of an original concentration of viaduct rainwater, a carbon source dosage of 800 mg, and an inoculation amount of 1%, the strain removed 92.62%, 6.98%, and 6.16% of NH₄⁺-N, TN, and TP, respectively from the actual viaduct rainwater; more interestingly, the removal rates of NH₄⁺-N and TN were 43.26% and 78.02%, respectively, even without carbon source addition. It seems that there is no need for carbon source addition to remove nitrogen from the actual viaduct rainwater for the strain. To sum up, the carbon-fixing bacteria 1C-1 presents an obvious nitrogen and phosphorus removal effect (especially for nitrogen) for viaduct rainwater treatment and has application potential. Full article

Climate change has aggravated the frequency and severity of extreme weather events, particularly in flood-related hazards. Cities nowadays face significant challenges in stormwater management from frequent heavy rainfalls. Traditional urban drainage systems can no longer cope with large amounts of surface runoff; cities are searching for new ways to deal with urban stormwater. Green roofs and other nature-based solutions have been widely used for stormwater management by combining water purification and retention functions but have not yet fully solved the flood problems. This article aims to (1) explore the different aspects of urban water management, particularly the urban stormwater topic, and (2) identify the existing solutions and discuss the potential and barriers to integrated solutions implementation. By introducing the concept of four domains and finding the overlapping area to investigate, we analyzed different solutions to reduce rainwater runoff from the roof and ground level, aiming at building and district scales. This paper proves that further research direction could constitute an integrated system to work together for urban stormwater management. Full article