Water in the Green Economy: Capacity Development Aspects

This book discusses needs related to capacity development for water resources management, including water supply and sanitation, in the context of the green economy. It showcases theoretical and practical approaches with proven success. Most contributions come from members and partners within the interagency mechanism, UN-Water. The 11 case studies in this book range from innovative design and delivery of capacity development programs related to water in the green economy, market mechanisms, and quality control procedures supporting capacity development success towards the practical implementation of programs to enhance individual and institutional capacity

Characterization of urban water use and performance evaluation of conservation practices using the Integrated Urban Water Model in São Paulo, Brazil

2018 Fall.Includes bibliographical references.Increasing urban population around the globe has intensified the need for water, food and energy. The residential sector is responsible for the highest water use in urban settings. Understanding the factors affecting water use helps to improve management strategies, incentivize conservation practices, develop public educational events, feed demand forecasting models and support policy creation. Modelling urban water demand in the long-term is a complex process because of incorporation of multiple dynamic components in the urban-environment system. The Integrated Urban Water Model – IUWM – offers capabilities of long-term modelling by using a mass-balance approach for urban water demand predictions and potential demand reductions assessment. A combination of climate anomalies, water resources management practices over the years and watershed conservation contributed to the water shortage in Southeastern Brazil in 2014-2015. In the city of São Paulo, the shortage was worsened by drops in reservoir levels, rise in water use patterns and in number of inhabitants, and the historical tendency to neglect local water sources. Residential water demand, which accounts for 84% of the total water use, faced compulsory reductions through behavioral changes and reuse of graywater and roof runoff harvesting. The goals of this study are to apply IUWM to the city of São Paulo to quantify savings produced by graywater and roof runoff use and to evaluate the potential of conservation practices for demand reduction. The first part of the study focuses on exploring differences in water demand patterns under shortage conditions using a water use time-series from 2013-2017. In this part, IWUM is trained to estimate indoor and outdoor demand through calibration procedures. Determinants of water demand are also investigated through a multiple linear regression, which identified household size and socioeconomic variables as having a significant effect in water use. The second portion focuses on applying IUWM to evaluate reductions during the shortage and performance of graywater, stormwater, roof runoff harvesting and effluent reuse for potable and non-potable purposes. Climate change was added to assess shifts in performances of conservation practices due to future reductions in precipitation. Lastly, a comparison of maximum potential and benefits of fit-for-purpose technology adoption is done using a cost-benefit matrix. The matrix was adapted for required treatment representing cost and percentage reductions in water demand as benefit. The results of this work support decision-making with respect to conservation practices adoption by enhancing the list of options to manage water demand, especially during shortage conditions. Ultimately, these results can encourage development of water reuse policies in Brazil

Views and behaviours of municipal actors relating to climate change and water management: the case of local municipal water management and social networks

Climate change is projected to impact the hydrological cycle and have a negative effect on water supply. In South Africa, water to the end user is supplied by local municipalities, and thus municipalities are likely to benefit from adapting to these climate impacts. This research aims to understand the views and behaviours of local municipal actors towards water management and climate change, and how these views and behaviours influence the resilience of their water supply system in the face of climate change. A secondary aim of the thesis was to determine if the advice networks, where the actors receive the bulk of their information from, influenced the actor’s views and behaviours around water management, climate change, and adaptation, using a social network approach. The study area focused on five local municipalities in the West Coast District of South Africa. This research made use of a mixed methods approach, utilising both qualitative and quantitative data, obtained using semi-structured interviews with a structured component. Qualitative data were used to collect water management-related views and behaviours of municipal actors, whilst quantitative data were collected to determine social network characteristics. The views and behaviours on water demand and supply management of the actors interviewed tended to differ. Actors’ views on ideal water management approaches were more concerned with the long-term sustainability of water resources through raising awareness and managing existing infrastructure better. Actor’s preferred behaviours however focused on immediate relief to water shortages, by augmenting existing supply and enforcing restrictions. These findings imply that actors respond reactively to drought, and not proactively. In terms of climate change, actors showed a clear understanding of climate change and its risks to water management. Actors understood how climate change adaptation could be used to make their municipalities’ water supply more resilient, by utilising sustainable sources of water or through ecosystem-based adaptation, however it was found that municipal plans and behaviours did not generally reflect these views. Social network characteristics such as strengths of ties, and the existence of multiplex ties, did not appear to influence the sharing of behaviours or views between the actor and their given advice network. It was thus theorised that institutional lock-in and hierarchical governance might play a larger role in influencing views and behaviours than the actors’ social networks. The reactive responses by actors to issues of water demand or supply can lead to poor resilience in the face of climate change, where cases of drought and water shortages may become more frequent. Whilst municipal actors are aware of these changing conditions and risks, the limitations placed on them by governance structures and lock-in impact their ability to be proactive. More work needs to be done to ensure sustainable and resilient water management interventions are implemented at the local municipal level. Additionally, lockin, both institutional and technological, could usefully be challenged to allow for innovative ideas to enter the realm of water management at the local municipal level

Climate risk management options in the water sector

M.Sc., Faculty of Science, University of the Witwatersrand, 2011Existing water management initiatives, strategies and policies in South Africa, ranging from the overarching water management legislative framework to the local-level practical operational aspects, were examined as a component of this project. The integration between National Strategies pertaining to water resource management and local implementation was addressed in terms of examining Water Conservation and Demand Management approaches and assessing the effectiveness of these approaches in addressing climate change risk factors in the water sector. Current South African regulatory instruments in the water sector allow adaptation and flexibility in order to address climate change impacts on the water resources in South Africa. The greatest obstacle in the implementation of effective Integrated Water Resource Management (IWRM) for climate change adaptation strategies is the lack of institutional support required from national levels of government to local municipalities. There is also a lack of strategic guidance and support in the form of policies specific to climate risk in the water sector in South Africa. Another important aspect of the IWRM, namely social learning, also suffers in the process due to lack of participation from key stakeholders and limited integration amongst interdependent sectors

A quantitative survey of the power saving potential in IP-Over-WDM backbone networks

The power consumption in Information and Communication Technologies networks is growing year by year; this growth presents challenges from technical, economic, and environmental points of view. This has lead to a great number of research publications on "green" telecommunication networks. In response, a number of survey works have appeared as well. However, with respect to backbone networks, most survey works: 1) do not allow for an easy cross validation of the savings reported in the various works and 2) nor do they provide a clear overview of the individual and combined power saving potentials. Therefore, in this paper, we survey the reported saving potential in IP-over-WDM backbone telecommunication networks across the existing body of research in that area. We do this by mapping more than ten different approaches to a concise analytical model, which allows us to estimate the combined power reduction potential. Our estimates indicate that the power reduction potential of the once-only approaches is 2.3x in a Moderate Effort scenario and 31x in a Best Effort scenario. Factoring in the historic and projected yearly efficiency improvements ("Moore's law") roughly doubles both values on a ten-year horizon. The large difference between the outcome of Moderate Effort and Best Effort scenarios is explained by the disparity and lack of clarity of the reported saving results and by our (partly) subjective assessment of the feasibility of the proposed approaches. The Moderate Effort scenario will not be sufficient to counter the projected traffic growth, although the Best Effort scenario indicates that sufficient potential is likely available. The largest isolated power reduction potential is available in improving the power associated with cooling and power provisioning and applying sleep modes to overdimensioned equipment

On IP over WDM burst-switched long haul and metropolitan area networks

The IP over Wavelength Division Multiplexing (WDM) network is a natural evolution ushered in by the phenomenal advances in networking technologies and technical breakthroughs in optical communications, fueled by the increasing demand in the reduction of operation costs and the network management complexity. The unprecedented bandwidth provisioning capability and the multi-service supportability of the WDM technology, in synergy with the data-oriented internetworking mechanisms, facilitates a common shared infrastructure for the Next Generation Internet (NGJ). While NGI targets to perform packet processing directly on the optical transport layer, a smooth evolution is critical to success. Intense research has been conducted to design the new generation optical networks that retain the advantages of packet-oriented transport prototypes while rendering elastic network resource utilization and graded levels of service. This dissertation is focused on the control architecture, enabling technologies, and performance analysis of the WDM burst-switched long haul and Metropolitan Area Networks (MANs). Theoretical analysis and simulation results are reported to demonstrate the system performance and efficiency of proposed algorithms. A novel transmission mechanism, namely, the Forward Resource Reservation (ERR) mechanism, is proposed to reduce the end-to-end delay for an Optical Burst Switching (OBS)-based IP over WDM system. The ERR scheme adopts a Linear Predictive Filter and an aggressive reservation strategy for data burst length prediction and resource reservation, respectively, and is extended to facilitate Quality of Service (QoS) differentiation at network edges. The ERR scheme improves the real-time communication services for applications with time constraints without deleterious system costs. The aggressive strategy for channel holding time reservations is proposed. Specifically, two algorithms, the success probability-driven (SPD) and the bandwidth usage-driven (BUD) ones, are proposed for resource reservations in the FRRenabled scheme. These algorithms render explicit control on the latency reduction improvement and bandwidth usage efficiency, respectively, both of which are important figures of performance metrics. The optimization issue for the FRR-enabled system is studied based on two disciplines - addressing the static and dynamic models targeting different desired objectives (in terms of algorithm efficiency and system performance), and developing a \u27\u27crank back\u27\u27 based signaling mechanism to provide bandwidth usage efficiency. The proposed mechanisms enable the network nodes to make intelligent usage of the bandwidth resources. In addition, a new control architecture with enhanced address resolution protocol (E-ARP), burst-based transmission, and hop-based wavelength allocation is proposed for Ethernet-supported IP over WDM MANs. It is verified, via theoretical analysis and simulation results, that the E-ARP significantly reduces the call setup latency and the transmission requirements associated with the address probing procedures; the burst-based transport mechanism improves the network throughput and resource utilization; and the hop-based wavelength allocation algorithm provides bandwidth multiplexing with fairness and high scalability. The enhancement of the Ethernet services, in tandem with the innovative mechanisms in the WDM domain, facilitates a flexible and efficient integration, thus making the new generation optical MAN optimized for the scalable, survivable, and IP-dominated network at gigabit speed possible

The International Demand Management Framework Stage 1

This report forms part of a larger study (Stage 1 of the International Demand Management Framework (IDMF)) which has been undertaken under the auspices of the International Water Association Task Force 7 of the Specialist Group Efficient Operation and Management. Current practice often utilises litres per capita per day (LCD) to describe and forecast water demand; however this practice has been found to be limited for planning purposes within water utilities. In its place, an emerging way forward is based on disaggregation of demand and robust comparison of both demand and supply options to improve reliability. Disaggregation of demand into sectors and end uses allows accurate forecasting of demand and strategic design of demand management options which may be used in complement to supply options. The findings indicate that Canal de Isabel II has completed excellent work in certain areas, such as drought and risk management, management of water losses, knowledge of supply and distribution system, and sector and end use data collection. There remains significant opportunity for Canal de Isabel II to incorporate other improvements toward best practice, including the following: ·approach the planning process in a coherent way that considers both demand and supply options and works through a logical sequence of steps ·utilise in-depth knowledge of sector and end-uses to strategically identify and design demand management options ·compare demand and supply options using a consistent economic analysis so that the solutions with the lowest cost to society can be selected and implemented ·involve a larger group of stakeholders at appropriate points in the planning process ·conduct pilot and implementation of chosen demand management options to initiate on-going learning about what works and doesn't in the local context & ·monitor and evaluate pilot and implementation programs using robust statistical methods

Wavelength tunable transmitters for future reconfigurable agile optical networks

Wavelength tuneable transmission is a requirement for future reconfigurable agile optical networks as it enables cost efficient bandwidth distribution and a greater degree of transparency. This thesis focuses on the development and characterisation of wavelength tuneable transmitters for the core, metro and access based WDM networks. The wavelength tuneable RZ transmitter is a fundamental component for the core network as the RZ coding scheme is favoured over the conventional NRZ format as the line rate increases. The combination of a widely tuneable SG DBR laser and an EAM is a propitious technique employed to generate wavelength tuneable pulses at high repetition rates (40 GHz). As the EAM is inherently wavelength dependant an accurate characterisation of the generated pulses is carried out using the linear spectrogram measurement technique. Performance issues associated with the transmitter are investigated by employing the generated pulses in a 1500 km 42.7 Gb/s circulating loop system. It is demonstrated that non-optimisation of the EAM drive conditions at each operating wavelength can lead to a 33 % degradation in system performance. To achieve consistent operation over a wide waveband the drive conditions of the EAM must be altered at each operating wavelength. The metro network spans relatively small distances in comparison to the core and therefore must utilise more cost efficient solutions to transmit data, while also maintaining high reconfigurable functionality. Due to the shorter transmission distances, directly modulated sources can be utilised, as less precise wavelength and chirp control can be tolerated. Therefore a gain-switched FP laser provides an ideal source for wavelength tuneable pulse generation at high data rates (10 Gb/s). A self-seeding scheme that generates single mode pulses with high SMSR (> 30 dB) and small pulse duration is demonstrated. A FBG with a very large group delay disperses the generated pulses and subsequently uses this CW like signal to re-inject the laser diode negating the need to tune the repetition rate for optimum gain-switching operation. The access network provides the last communication link between the customer’s premises and the first switching node in the network. FTTH systems should take advantage of directly modulated sources; therefore the direct modulation of a SG DBR tuneable laser is investigated. Although a directly modulated TL is ideal for reconfigurable access based networks, the modulation itself leads to a drift in operating frequency which may result in cross channel interference in a WDM network. This effect is investigated and also a possible solution to compensate the frequency drift through simultaneous modulation of the lasers phase section is examined

On the linkage between atmospheric circulation changes and Arctic climate change

Polar amplification is a prominent feature of recent and projected climate change. The Arctic region shows some of the strongest signs of climate change, including sea-ice retreat and temperatures increasing at twice the rate averaged over the northern hemisphere. A major concern for humanity is the sea-level rise associated with the melting of the ice-sheets and glaciers due to climate change. The atmospheric circulation transports an amount of energy into to the Arctic equivalent that received by the Arctic from the Sun. Thus, the atmospheric energy transport is an important subject to study in the light of Arctic climate change. The atmospheric energy transport may be decomposed into contributions by planetary-scale waves such as Rossby waves and small-scale waves such as cyclones. The energy transport contributions by the different length-scale separated systems are shown to affect the Arctic differently. The meridional energy transport is separated into length-scale contributions using a Fourier-series-based approach. Here we evaluate this approach by comparing it to a novel wavelet-based length-scale decomposition, developed as a part of this project. Further a machine-learning-based length-scale decomposition approximator is developed. The approximator may be applied to climate model output to investigate future changes in the length-scale decomposed energy transport. From the comparisons it is apparent that both the Fourier and wavelet-based length-scale decompositions are skilled approaches, which produce physically meaningful decompositions. Additionally, the Fourier-based decomposition is further developed to yield a length-scale decomposition on a latitude-longitude grid. Once evaluated the Fourier and wavelet-based decompositions are applied to investigate the effects of recent climate change on the atmospheric energy transport, and how these changes affect the Arctic and the Greenland ice-sheet. Through these studies it is conspicuous that shifts of energy transport between length-scale components has occurred during the last decades, and that these shifts have contributed to Greenland ice-sheet melt and Arctic warming