• Energy Research
• 6. Clean water close

Ecosystem-based Adaptation (EbA) involves using services on which human well-being depends to help people adapt to the impacts of climate change. Aiming at strengthening ecosystem resilience and reducing ecosystem and people’s vulnerability, EbA has been encouraged worldwide as an option for climate change. Payments for Ecosystem Services (PES) are incentives offered to farmers and landowners to provide an ecological service and are currently proposed as a method for EbA and water resources sustainability on a global scale. However, organized information on PES in Brazil is limited. This paper provides a concise review of PES initiatives in the Brazilian Atlantic Forest, where various PES projects on watershed protection (Water-PES) have been set up. We found 16 ongoing Water-PES in the Brazilian Atlantic Forest. The first initiative was launched in 2005 and since then these projects have grown rapidly. In spite of the advances made in many of these initiatives, they seldom have baseline hydrologic data and an implemented strategy for ecohydrological monitoring. Thus, we discuss how PES projects could be more effective by implementing hydrological monitoring based on ecohydrological concepts. Special attention has been given to explaining how the recent Impact-Vulnerability-Adaptation idea could be integrated into Water-PES. As can be seen from the review, these projects contribute as EbA options for climate change, thereby carrying practical implications for environmental policy makers.

Abstract Nature-based Solutions (NbS) are presented as an alternative and decentralized solutions with different application scales for problems addressed to urban expansion as water quality reduction and floods. The usage of control strategies and mathematical modeling techniques has shown promising results for optimizing hydraulic and water treatment processes. The Digital Twins (DT) as process integration technology are widely used in industry, and recently these technique usages in urban water systems are showing effective results in both management and planning. However, there is a lack of proper literature definition for DT applied to NbS, especially for stormwater and transboundary water security projects. Thus, this paper sought through a literature review to access the existing conceptual challenges and the DT definition as a framework, identify how the mathematical modeling reported in the literature can improve the DT development, and evaluate the potential benefits associated with the application of DT in NbS.

The increase in urbanization and climate change projections point to a worsening of floods and urban river contamination. Cities need to adopt adaptive urban drainage measures capable of mitigating these drivers of change. This study presents a practical methodology for a modular design of bioretention systems incorporating land use and climate change into existing sizing methods. Additionally, a sensitivity analysis for these methods was performed. The methodology was applied to a case study in the city of Sao Carlos, SP, Brazil. Three application scales were evaluated: property scale (PS), street scale (SS) and neighborhood scale (NS) for three temporal scenarios: current, 2015–2050 and 2050–2100. The choice of the sizing method was the factor with greatest influence on the final bioretention performance, as it considerably affected the surface areas designed, followed by the hydraulic conductivity of the filtering media. When analyzing the sensitivity of the parameters for each method, the runoff coefficient and the daily precipitation with 90% probability were identified as the most sensitive parameters. For the period 2050–2100, there was an increase of up to 2×, 2.5× and 4× in inflow for PS, SS and NS, respectively. However and despite the great uncertainty of future drivers, bioretention performance would remain almost constant in future periods due to modular design.

The sustainability of water utility companies is threatened by non-stationary drivers, such as climate and anthropogenic changes. To cope with potential economic losses, instruments such as insurance are useful for planning scenarios and mitigating impacts, but data limitations and risk uncertainties affect premium estimation and, consequently, business sustainability. This research estimated the possible economic impacts of business interruption to the Sao Paulo Water Utility Company derived from hydrological drought and how this could be mitigated with an insurance scheme. Multi-year insurance (MYI) was proposed through a set of “change” drivers: the climate driver, through forcing the water evaluation and planning system (WEAP) hydrological tool; the anthropogenic driver, through water demand projections; and the economic driver, associated with recent water price policies adopted by the utility company during water scarcity periods. In our study case, the evaluated indices showed that MYI contracts that cover only longer droughts, regardless of the magnitude, offer better financial performance than contracts that cover all events (in terms of drought duration). Moreover, through MYI contracts, we demonstrate solvency for the insurance fund in the long term and an annual average actuarially fair premium close to the total expected revenue reduction.

AbstractRisk management has reduced vulnerability to floods and droughts globally1,2, yet their impacts are still increasing3. An improved understanding of the causes of changing impacts is therefore needed, but has been hampered by a lack of empirical data4,5. On the basis of a global dataset of 45 pairs of events that occurred within the same area, we show that risk management generally reduces the impacts of floods and droughts but faces difficulties in reducing the impacts of unprecedented events of a magnitude not previously experienced. If the second event was much more hazardous than the first, its impact was almost always higher. This is because management was not designed to deal with such extreme events: for example, they exceeded the design levels of levees and reservoirs. In two success stories, the impact of the second, more hazardous, event was lower, as a result of improved risk management governance and high investment in integrated management. The observed difficulty of managing unprecedented events is alarming, given that more extreme hydrological events are projected owing to climate change3.

Monitoring water quality is an essential tool for the control of pollutants and pathogens that can cause damage to the environment and human health. However, water quality analysis is usually performed in laboratory environments, often with the use of high-cost equipment and qualified professionals. With the progress of nanotechnology and the advance in engineering materials, several studies have shown, in recent years, the development of technologies aimed at monitoring water quality, with the ability to reduce the costs of analysis and accelerate the achievement of results for management and decision-making. In this work, a review was carried out on several low-cost developed technologies and applied in situ for water quality monitoring. Thus, new alternative technologies for the main physical (color, temperature, and turbidity), chemical (chlorine, fluorine, phosphorus, metals, nitrogen, dissolved oxygen, pH, and oxidation–reduction potential), and biological (total coliforms, Escherichia coli, algae, and cyanobacteria) water quality parameters were described. It was observed that there has been an increase in the number of publications related to the topic in recent years, mainly since 2012, with 641 studies being published in 2021. The main new technologies developed are based on optical or electrochemical sensors, however, due to the recent development of these technologies, more robust analyses and evaluations in real conditions are essential to guarantee the precision and repeatability of the methods, especially when it is desirable to compare the values with government regulatory standards.