A comprehensive review on integrating sustainable practices and circular economy principles in concrete industry.

This comprehensive review explores the integration of circular economy principles into the concrete industry, emphasizing their role in enhancing sustainability and resource efficiency. It covers the fundamental concepts of circular economy and examines the application of Life Cycle Assessment (LCA) in evaluating the environmental impacts of concrete production. The review highlights innovative strategies for recycling, reuse, waste reduction, and resource optimisation, showcasing how these approaches can transform concrete production practices. It also addresses the policy considerations, economic implications, and societal impacts associated with adopting circular economy practices. Furthermore, the review investigates recent technological advancements in circular concrete production, including self-healing concrete and 3D printing. By summarizing these findings and offering practical recommendations, the review aims to support the industry in transitioning towards more sustainable practices. This detailed analysis provides valuable insights into the benefits and challenges of circular economy adoption, helping stakeholders make informed decisions for a greener concrete sector.

Bio-organic substitution in tobacco (Nicotiana tabacum L) cultivation: Optimum strategy to lower carbon footprint and boost net ecosystem economic benefit.

The partial substitution of organic manure for chemical nitrogen fertilizers, known as organic substitution, is widely regarded as a cleaner and more sustainable production strategy. However, few studies have quantified greenhouse gas emissions, product income and net ecosystem economic benefit (NEEB) using a life cycle assessment (LCA) approach, particularly for typical tobacco (Nicotiana tabacum L.) production. Here, we quantified the yield and quality of a typical tobacco production in Qujing, Yunnan, China, through field experiments and calculated its carbon footprint and NEEB using the LCA approach. Four organic substitution strategies were established with equal nitrogen inputs, including synthesized chemical fertilizer (SN), farmyard organic manure (NF), commercial organic manure (NC), and bio-organic (Trichoderma viride Pers.) manure (NT), each substituting 15% of synthesized nitrogen fertilizer. Compared to the SN strategy, the NT strategy significantly increased yield and income by 10.3% and 9.6%, respectively. In contrast, the NF strategy significantly reduced income, while the NC strategy showed no significant difference. Both the NC and NT strategies significantly reduced N2O cumulative emissions (by 15.9% and 8.0%, respectively), increased δSOC (by 38.4% and 15.0%, respectively), and decreased carbon footprint compared to the SN strategy. However, the NF strategy significantly increased the income-scaled carbon footprint, even though it also notably reduced N2O cumulative emissions (by 22.6%) and increased δSOC (by 7.9%). The NT strategy achieved a win-win scenario of low environmental risk and high economic returns of tobacco production with significantly increased NEEB (by 10.6%) compared to the SN strategy (37.60 × 103 CNY yr-1). This suggests that the bio-organic Trichoderma manure substituting 15% synthesized nitrogen fertilizer is the best organic substitution strategy for sustainable tobacco production.

Optimizing solarized desalination unit through the implementation of 4-step MED method using energy, exergy, economic and environmental analysis.

The consumption of thermal energy in thermal desalination plants leads to a higher price for the fresh water they produce compared to other methods. By utilizing optimization techniques, it is possible to lower both energy consumption and price. The focus of this paper is on optimizing a solarized desalination unit through the implementation of the 4-step MED method with a PTC collector. To achieve this objective, the NSGA II algorithm was implemented in MATLAB using a function for optimization. This algorithm is known for its cost-effectiveness and high energy efficiency. According to the results, there has been an improvement in the fresh water flow rate, desalination efficiency, and GOR, with values reaching 126.87, 53.6%, and 3.66 respectively, compared to the previous values of 116.5, 49.21%, and 3.32. In the ideal condition, the power generated is 6089 kW, priced at 3.28 cents per kilowatt, and the cost of producing fresh water is 8.49 dollars per cubic meter, which decreases as the process lifespan increases. Solar collectors and thermal tanks account for the largest portion (64%) of exergy destruction, as indicated by the exergy analysis. Optimization of the process has led to energy and exergy efficiencies of 59.8% and 58%, respectively, representing a notable enhancement of around 10% in the system's lifespan. The optimal mode also includes the completion of the sensitivity analysis. The process was subjected to LCA analysis, and the results indicated that the largest impact is on human health, with the collectors and thermal storage tanks being responsible for most of the pollution. As a result, the optimized process has delivered outstanding results while also being environmentally conscious.

Process innovations and circular strategies for closing the water loop in a process industry.

By implementing advanced wastewater treatment technologies coupled with digital tools, high-quality water is produced to be reused within the industry, enhancing process efficiency and closing loops. This paper investigates the impact of three innovation tools (process, circular and digital) in a Solvay chemical plant. Four technologies of the wastewater treatment plant "WAPEREUSE" were deployed, predicting their performance by process modelling and simulation in the PSM Tool. The environmental impact was assessed using Life Cycle Assessment and compared to the impact of the current industrial effluent discharge. The circularity level was assessed through three alternative closed-loop scenarios: (1) conventional treatment and discharge to sea (baseline), (2) conventional and advanced treatment by WAPEREUSE and discharge to sea, (3) conventional and advanced treatment by WAPEREUSE and industrial water reuse through cross-sectorial symbiotic network, where effluents are exchanged among the process industry, municipality and a water utility. Scenario 1 has the lowest pollutants' removal efficiency with environmental footprint of 0.93 mPt/m3. WAPEREUSE technologies decreased COD by 98.3%, TOC by 91.4% and nitrates by 94.5%. Scenario 2 had environmental footprint of 1.12 mPt/m3. The cross-sectorial symbiotic network on the industrial value chain resulted in higher industrial circularity and sustainability level, avoiding effluents discharge. Scenario 3 is selected as the best option with 0.72 mPt per m3, reducing the environmental footprint by 21% and 36% compared to Scenarios 1 and 2, respectively.

Assessing environmental sustainability of substitute feeding formulas for gilthead seabream (Sparus aurata) using Life Cycle Assessment.

The rise in fish and seafood consumption driven by aquaculture comes with its share of challenges and controversies, notably the need for expanded feed production. The use of fishmeal and fish oil to raise carnivorous fish has caused environmental problems, including ecosystem imbalance and habitat destruction, as well as ethical issues like fishing forage fish for feed instead of human consumption. Thus, the industry has been actively pursuing alternative feed ingredients to reduce reliance on fish-derived components. This progress in the aquaculture feed sector has made selecting the best feed solution complex across various fronts. This study aims to assess the environmental impacts of three feed formulations, each with different protein sources (poultry by-products, PMB, Tenebrio molitor larvae, TM, or Hermetia illucens larvae, HI), tailored for the gilthead seabream (Sparus aurata), a prized species in European aquaculture. The environmental sustainability of these alternatives was evaluated against benchmarks of fishmeal and fish oil-based feed. Employing a cradle-to-gate approach and a FU of 1 kg of product, the study utilized OpenLCA software supported by the Ecoinvent ® v3.7.1 database. The results focused on the production stages of each ingredient, including logistical and transportation aspects leading up to the final formulation. All alternatives to traditional feed demonstrated either comparable or superior environmental performance (i.e. - 66 % of PMB-f, -33 % of TM-f and - 29 % HI-f kgCO2 eq) with few exceptions for TM-f. This investigation highlighted how integrating innovative ingredients could positively impact the environmental footprint of aquafeed production chains. Furthermore, the main hotspots in the alternative feed formulas life cycles have been identified and viable alternatives for improvement have been proposed, such as selecting different input materials or enhancing energy efficiency. This assessment allows to guide the selection of more environmentally friendly feed formulations before their integration into aquaculture chain processes.

Reversibly crosslinked polyurethane fibres from sugar-based 5-chloromethylfurfural: Synthesis, fibre-spinning and fibre-to-fibre recycling.

The development of recyclable crosslinked thermosetting fibres is a challenging research topic. In the present work, we have designed and synthesized polyurethane fibres from fructose-derived 5-chloromethylfurfural (CMF) and lignin-derived monomeric phenols. The greenhouse gas emissions associated with the production of CMF showed comparable results to that of 5-hydroxymethylfurfural (HMF), a high potential sugar-based platform molecule. The wet-spun biobased polyurethane fibres produced could be conveniently crosslinked using Diels-Alder chemistry to effectively enhance the glass transition temperature and mechanical properties. At a mildly elevated temperature (140 °C), the chemically crosslinked fibres could be effectively de-crosslinked, which enabled complete separation from a mixture with poly(ethylene terephthalate) (PET) and cotton fibres. These results outline a potential strategy to design and fabricate new biobased fibres with reversible crosslinking, which may enable fibre-to-fibre recycling.

A new paradigm for whole-chain low-carbon utilization of food waste secondary waste based on multivariate evaluations.

The rapid growth of China's food and beverage industry has led to a significant increase in food waste, presenting major challenges for its disposal. Anaerobic digestion is the primary treatment method, but its by-products-biogas slurry (BS) and biogas residue (BR)-pose additional treatment challenges. This study proposes and evaluates three management scenarios for these by-products: (1) BS sewage treatment with BR incineration (S1), (2) BS land application with BR composting (S2), and (3) BS sewage treatment with BR composting (S3). The scenarios were comprehensively assessed using material flow analysis, life cycle assessment, and economic benefit analysis. The findings show that S2 achieves the highest carbon utilization efficiency (80.16%) and delivers superior environmental and economic benefits. Scaling up S2 by 2030 could reduce national carbon emissions by 1817.8 kilotons and generate $11.14 billion in economic profit. This study offers a novel model for the sustainable, low-carbon utilization of food waste by-products, providing valuable insights for future organic waste management.

Case study of the environmental impacts and benefits of a PBF-LB additively manufactured optimized filtrate nozzle.

In this paper, we present a comprehensive case study of a laser-based powder bed fusion-manufactured optimized filtrate nozzle, focusing on environmental impacts and benefits. The scope of the study covers the raw material production, part manufacturing and use phases. We compare the results for similar components manufactured by conventional, mainly material-removing manufacturing technologies. Primary data, measured from processes, are utilized for life cycle assessment calculations, which are completed with database data when necessary. The results show that by exploiting the design freedom of additive manufacturing, it is possible to achieve positive environmental benefits, namely, a 40% reduction in the carbon footprint during the use phase, although the manufacturing phase per se requires a similar amount or even more resources than the conventional manufacturing route. In addition to environmental benefits, we present here some other potential benefits for using optimized, additively manufactured parts.

Exploring the Antioxidant and Anti-Inflammatory Potential of Saffron (Crocus sativus) Tepals Extract within the Circular Bioeconomy.

Repurposing saffron (Crocus sativus) waste presents a sustainable strategy for generating high-value products within the bioeconomy framework. Typically, flower components are discarded after stigma harvest, resulting in significant waste-350 kg of tepals per kilogram of stigmas. This research employed a comprehensive approach, integrating bioactivity studies (in vitro and in silico) with Life Cycle Assessment (LCA) evaluations, to extract and assess bioactive compounds from C. sativus tepals sourced in Tuscany, Italy. Phytochemical characterization using UPLC-MS/MS revealed a high abundance and variety of flavonoids in the hydro-ethanolic extract (CST). The antioxidant capacity was validated through various assays, and the ability to mitigate H2O2-induced oxidative stress and enhance fermentation was demonstrated in Saccharomyces cerevisiae. This study reports that C. sativus tepals extract reduces oxidative stress and boosts ethanol fermentation in yeast, paving the way for applications in the food and biofuels sectors. Further validation in RAW 264.7 macrophages confirmed CST's significant anti-inflammatory effects, indicating its potential for pharmaceutical, cosmeceutical, and nutraceutical applications. In silico studies identified potential targets involved in antioxidant and anti-inflammatory processes, shedding light on possible interaction mechanisms with Kaempferol 3-O-sophoroside (KOS-3), the predominant compound in the extract. The integration of LCA studies highlighted the environmental benefits of this approach. Overall, this research underscores the value of using waste-derived extracts through "green" methodologies, offering a model that may provide significant advantages for further evaluations compared to traditional methodologies and supporting the circular bioeconomy.

Comparative life cycle assessment of PBAT from fossil-based and second-generation generation bio-based feedstocks.

With the increasing demand for plastics, plastic pollution is growing rapidly. A significant amount of plastic has leaked into the environment, leading to severe environmental issues. Biodegradable plastics are considered promising alternatives to conventional durable plastics, and the environmental impacts of biodegradable plastics have received increasing attention. Poly (butylene adipate-co-terephthalate) (PBAT) is a commercial and cost-competitive biodegradable polymer and has been applied in the packaging and agriculture sectors. The environmental performances of PBAT with second-generation feedstocks from forestry waste have been rarely investigated. Since China is the leading global producer and exporter of PBAT polymer, Chinese cradle-to-gate life cycle inventories of PBAT were compiled in this study. A comparative life cycle assessment (LCA) was conducted to explore the potential for environmental performance of PBAT with second-generation bio-based feedstock compared to fossil-based PBAT and conventional plastics. The results showed that feedstocks contributed to more than 70 % of 18 environmental impact categories of fossil-based PBAT. In comparison, PBAT with second-generation bio-based feedstock reduces the environmental loads in 16 impact categories by 15-85 %, and renewable energy substitution has the potential to reduce environmental impacts by 10 %. Bio-based PBAT performs better than PVC, PP, HDPE, LDPE, and PET in 16 impact categories by 15-80 %. Bio-based PBAT has GWP of 3.72 kg CO2 eq, which is 37 % lower than fossil-based PBAT (5.89 kg CO2 eq) and 18-32 % lower than conventional plastics. Since feedstock dominates the environmental performance of PBAT, the development of biomanufacturing technologies for bio-based polymers and chemicals could significantly improve environmental performance of biodegradable plastics and promote the sustainable development of the plastic industry. Results could serve as the basis for environmental impact and mitigation strategies for biodegradable plastics with bio-based feedstocks, as well as the sustainable development of the PBAT industry.

Optimizing the greenhouse gas emissions of waste transfer and transport: An integration of life cycle assessment and vehicle routing problem.

This study presents a comprehensive analysis of greenhouse gas (GHG) emissions associated with waste transfer and transport, incorporating derived leachate treatment-a factor often overlooked in existing research. Employing an integration model of life cycle assessment and a vehicle routing problem (VRP) methods, we evaluated the GHG reduction potential of waste transfer and transport system. Two Chinese counties with different topographies and demographics were selected, yielding 80 scenarios that factored in waste source separation as well as vehicle capacity, energy sources, and routes. The functional unit (FU) is transferring and transporting 1 tonne waste and treating derived leachate. The GHG emissions varied from 12 to 39 kg CO2 equivalent per FU. Waste source separation emerged as the most impactful mitigation strategy, not only for the studied system but for an integrated waste management system. Followings are the use of larger capacity vehicles and electrification of the vehicles. These insights are instrumental for policymakers and stakeholders in optimizing waste management systems to reduce GHG emissions.

Embedding Water-Energy-Food nexus and circularity assessment for organization benchmarking: A case study for dairy farms.

The Water-Energy-Food (WEF) nexus approach is increasingly being used for supporting a transition to sustainable development, with initiatives involving the concept of circular economy (CE). In the agricultural sector in particular, assessing this nexus is crucial to ensure food security, control the consumption of key resources such as water and energy, as well as measure atmospheric emissions linked to climate change. This manuscript aims to propose a novel approach by coupling the WEF nexus with a circularity indicator, seeking to capture in a single index (the WEF+CEi) both performances in a sample of companies. The novel approach is applied to 30 dairy farms located in Galicia (NW Spain) to benchmark them in a holistic manner. To do this, the WEF nexus of each farm was represented through the following indicators: carbon footprint, water footprint, energy footprint, and food productivity. In addition, the percentage of circularity for each farm, and for the agro-industrial cooperative was measured thanks to the application of a circularity tool in percentage terms. Finally, the WEF+CEi indicator was obtained using the multicriteria mathematical tool of Data Envelopment Analysis (DEA). The results show that without considering the agro-industrial cooperative, the system is 51 % circular. On the other hand, considering the farms and the cooperative, the system goes up to 80 % of circularity. Finally, the proposed approach can support decision-making and provide insights for producers and stakeholders in the area.

Contribution of waste management to a sustainable textile sector.

With increasing textile consumption and limited sorting and recycling capacities, the EU faces major challenges in terms of managing its textile waste. This study investigates the environmental and socio-economic impacts of explorative policy scenarios for a more sustainable textile waste management system in Europe. These scenarios differ substantially in the amounts of textile waste generated and separately collected, closed-loop recycling capacities and textile waste exports. Our results show that sustainable textile waste management remains highly relevant for the sector. Still, without addressing in parallel prevention of textile waste generation via production and consumption patterns, a climate-neutral and circular textiles sector will be hard to achieve. Interventions in the waste management of textiles could reduce global warming impacts by up to 22.3 Mt CO2 per year, which translates to an 18% sector-wide impact by 2035. Depending on the intervention(s), the estimated required investment at present amounts to between 7 and 33 billion EUR. The study provides a valuable starting point for evidence-based decisions on future textile policymaking in Europe.

Life cycle environmental trade-off of decarbonising UK industrial clusters - A cradle to gate approach.

The industrial sector is a major source of greenhouse gas (GHG) emissions due to process emissions and a heavy reliance on fossil fuels for heat and power. Methods exist to produce low carbon versions of products made in industrial clusters, including hydrogen, carbon capture and storage and alternative production methods, but these could increase burdens to other areas of the environment, such as resource depletion and water scarcity. This study compares different decarbonisation pathways for ammonia, cement, methanol and steel produced in the UK, to determine whether decarbonising could result in unintended environmental consequences. To determine this, life cycle assessment was applied to compare 267 different pathways to the conventional (fossil fuel) baseline. We find that most pathways lead to GHG emission reductions (43 to 78 % on average) but would increase impacts to other areas of the environment, including metal resources and ecotoxicity (8 % to 5-fold and 19 % to 24-fold, on average respectively). This study is the first to assess decarbonisation pathways for unintended environmental impacts and is of interest to industry, policy makers and anyone modelling industrial lifecycle emissions.

Evaluating energy balance and environmental footprint of sludge management in BRICS countries.

Climate change is driving global endeavours to achieve carbon neutrality and renewable energy expansion. Sludge, a nutrient-rich waste, holds energy potential yet poses environmental challenges that need proper management. We conducted a comprehensive life cycle assessment to evaluate the energy balance and environmental footprint of the most commonly used sludge management scenarios in BRICS countries, namely Brazil, Russia, India, China, and South Africa. Technologies such as incineration and anaerobic digestion with energy recovery units (i.e., cogeneration unit) maximize energy balance and minimize the environmental footprint, with incineration showing a superior performance. Shifting sludge management scenarios from the worst to the best can boost energy production by 1.4-98.4 times and cut the environmental footprint by 1.5-21.4 times. In 2050, these improvements could lead to a 98-fold boost in energy generation and a 25-fold drop in carbon emissions, according to the Announced Pledges Scenarios. Optimizing parameters such as volatile solids and anaerobic digestion efficiency further boosts energy output and minimizes the environmental footprint. This study offers robust evidence to support sustainable sludge management and thus promote energy recovery and carbon neutrality goals, guide technological transitions, and inform policymaking for sustainable development.

A critical review of consumer responsibility in promoting sustainable cocoa production.

Consumer buying behavior can be defined as all the different steps that consumers follow before purchasing a good or service. Web browser research, involvement in online networking discussions, and a range of other activities might be a part of this process. Despite the negative effects of its production chain on the environment, and on the socio-economical condition of local farmers, chocolate products are among the most distributed food and beverage items in the world. In this review, the consumer responsibility for sustainable cocoa production is described. This study determines the consumer opinions and attitudes on the different operations pursued in the production chain of chocolate, from the collection of cocoa beans to their processing into different final products. For this, data on life cycle assessment from some studies was gathered to identify and investigate links between the production chain of different types of chocolate (dark, white, milk) and its impact on natural resources so that the sensitivity of consumers to purchase more sustainable products can be evaluated. This approach revealed that consumers will not only purchase chocolate because of its good quality or health benefits, but they also consider it the most sustainable product.

Route-level carbon dioxide emissions in intercity multimodal passenger transport: analytical framework and characteristics.

Understanding the CO2 emission characteristics and key mitigation pathways of intercity passenger transport is crucial for achieving sustainable development in the transport system. Using origin-destination data on travel between city pairs by various transportation modes, we employ the life cycle assessment (LCA) method to estimate route-level CO2 emissions from intercity multimodal passenger transport corridors, considering infrastructure construction and vehicle operation phases. Subsequently, a sensitivity analysis is conducted to assess the impact of 39 parameters associated with the construction phase, operation phase, and transportation modes on CO2 emissions from corridors. Trend analysis is employed to explore the future emission mitigation potential for the parameters that have the most significant impact on corridor emissions. Four intercity multimodal passenger corridors in China are selected as case studies. Results indicate that the CO2 emissions per passenger-kilometer from these corridors exhibit an approximate negative linear relationship with corridor lengths. The proportion of construction-related CO2 emission intensity of various intercity passenger transport modes varies significantly, ranging from 2.5 to 32.9%. In the medium term, effective emission-mitigation strategies should focus on decreasing private car gasoline consumption in three corridors under 200 km in length, as well as decreasing private car gasoline consumption and promoting clean electricity in the Xi'an-Yan'an corridor. In the long term, efforts should be placed on increasing electric private car share and promoting clean electricity. This study lays a crucial foundation for the refined management of CO2 emissions from future intercity passenger transport.

Environmental impacts of extensive beef production in Colombia by life cycle assessment: a case study.

The increase in the negative effects of global change promotes the search for alternatives to supply the demand for food worldwide aligned with the Sustainable Development Goals (SDGs) to ensure food security. Animal protein, which is a main source of nutrients in the diet of today's society, especially beef, which is one of the most demanded products nowadays, has been criticized not only for its high water consumption and land occupation for production but also for the emission of greenhouse gases (GHG) from enteric methane generated in the fermentation process within the bovine rumen and deforestation for the adaptation of pastures. This study is mainly motivated by the lack of quantifiable scientific information in Colombia on the environmental impacts of beef production. Therefore, it is intended to estimate some of the impacts of beef production in extensive systems using the life cycle assessment (LCA) method under a particular scenario considering all the production phases (from raw material to fattening, where the cattle are ready to be slaughtered). The study was conducted with data supplied by a farm in Antioquia, Colombia, and the functional unit (FU) was defined as 1 kg of live weight (LW). The scope of this study was gate-to-gate. "The 2019 Refinement to the 2006 IPCC Guidelines for National Greenhouse Gas Inventories" (IPCC  2006; IPCC 2019) was used to calculate methane and nitrous oxide emissions. LCA modeling was developed with Ecoinvent database v3.8 and the Umberto LCA + software. It was found that the most affected category of damage was ecosystem quality, which represents 77% of the total, followed by human health at 17% and resources at 6%. The category impact of agricultural land occupation is the one that represents the most significant contribution to the ecosystem quality endpoint, with a percentage of 87%, due to the soil's compaction and the loss of the soil's properties. Additionally, the obtained carbon footprint for the system was 28.9 kg of CO2-eq/kg LW.

Optimizing concrete for circularity: a comparative life cycle assessment of geopolymer and ordinary concrete.

Geopolymer concrete is a sustainable construction material developed with industrial by-products to eliminate the use of cement in concrete production. However, a cradle-to-cradle life cycle assessment (LCA) that accounts for the impact of service life is essential to comprehensively assess the environmental advantages of GPC. In this study, a comparative cradle-to-cradle LCA was performed for circular geopolymer concrete (CGPC), geopolymer concrete (GPC), and circular ordinary concrete (COC), as alternatives to Portland cement concrete (PCC). Also, the biases of common LCA resulted from ignoring service life and end-of-life scenarios were identified. Finally, the sustainability potentials of the alternative scenarios were evaluated. According to the cradle-to-cradle LCA using the adopted functional unit, GPC and CGPC significantly alleviated the environmental impact of cement production, such as global warming potential by about 53%. Ignoring the service life and end-of-life scenarios considerably changed the critical midpoint (ionizing radiation for CGPC and GPC) and endpoint indicators (resources for CGPC and GPC) and priority of alternative concretes. Finally, the CGPC and GPC showed a substantial increase of 213% and 276% in sustainability potential compared to PCC, respectively.

Life cycle environmental impacts of urban water systems in China.

Urban water systems in China are facing multiple challenges, including rapid urbanisation, climate change and infrastructure ageing. It is crucial to evaluate their environmental performance from a holistic perspective in planning and management processes. To the best of our knowledge, there is a lack of nationwide life cycle assessment (LCA) studies on China's urban water systems that cover all system stages. Therefore, this study aims to present a comprehensive and nationwide LCA analysis that pinpoints the environmental hotspots and their major sources across China. This study was conducted based on water utility databases at the province level, covering water abstraction and treatment, waterwork sludge treatment, water distribution, sewage collection, stormwater drainage, wastewater treatment and sewage sludge treatment. Nine environmental impact categories were calculated and analysed. The results reveal the inequity of environmental impacts across provinces, with overall impacts geographically higher in the east and south, lower in the west and north. However, at the functional unit level, the impacts in the northern and northeastern provinces are higher than other regions. Most environmental categories are dominated by multiple water system stages. The analyses of underlying drivers found that purchased electricity is the primary source of several environmental impacts. This study provides a holistic understanding of the environmental performance of China's urban water systems, offers some insights for comprehensive decision-making support on sustainable water system management, and can also serve as a benchmark for future scenario analysis to explore options for reducing environmental impact.