Developing roadmaps for the sustainable management of the urban water cycle: the case of ww reuse in Athens

In the context of water scarcity the interest in the reuse of treated wastewater as an alternative resource for non-potable uses has increased. Recent changes in the regulatory framework (JMD 145116/2011) and the introduction of guidelines and standards for reuse in Greece make a study of the implementation of wastewater reuse in Athens timely. The paper uses state-of-art metabolism modelling tools and approaches to develop and quantify a set of ¿roadmaps¿ towards wastewater reuse for the water company of Athens with the intention to support its sustainability agenda. The paper presents the candidate areas for wastewater reuse in Athens and describes the criteria for their designation, including assessment of suitable uses (such as industrial use, reforestation, crop irrigation, ground water recharge and urban and peri-urban uses) and estimation of their proximity to major Wastewater Treatment Plants (WWTPs). Different roadmaps are developed to assess the feasibility and quantify the effect of a progressive replacement of potable water with reclaimed water for the targeted uses and users. Each step of these roadmaps is simulated using the Urban Water Optioneering Tool (UWOT) which simulates and optimizes the entire urban water cycle, from source to tap. The paper concludes with a comparative assessment of the roadmaps based on the results of the simulations, taking into account the reduction of total water abstractions and the energy consumption for pumping and treatment of potable and reclaimed water. The results indicate that wastewater reuse can improve (a) the quantity and quality of surface and underground water; (b) the ecosystem services; (c) the efficiency of water use; and (d) the reliability of the existing water supply system of Athens.Papariantafyllou, E.; Makropoulos, C. (2013). Developing roadmaps for the sustainable management of the urban water cycle: the case of ww reuse in Athens. 13th International Conference of Environmental Science and Technology. http://hdl.handle.net/10251/3291

Developing An Integrated Modelling System For Blue-Green Solutions

Blue-green interventions represent the next level of integration for sustainable cities: that of an integrated urban water and urban green design, operation and management. The key concept is that a more holistic approach would present a win-win scenario, in which urban green would be utilized as infrastructure for water services (e.g. mitigating urban floods) while urban water infrastructure would be used as a source of irrigation for urban green, increasing their performance in a range of services including amenities, reducing heat island effects and increasing ecosystem services. However, this focus on integration brings into sharp relief another need: that of developing models and tools able to investigate the interactions between different green and blue system elements and processes. This “ecosystem” of models and tools presents a challenge due to its scope, in terms of development, but also the challenge of model integration. This paper discusses these challenges and furthermore proposes a three level approach to building an integrated modelling system for this case, which is able to: (a) support in the choice of appropriate models; (b) facilitate their linking in runtime and (c) enable the homogenization of results from the different models into common views supporting decision making. The use of standards including OpenMI and WaterML are discussed in the light of the proposed approach. The concept is tested using a limited set of models developed for blue-green solutions design and the preliminary results are presented and critically discussed. The paper concludes with suggestions on the way forward in this work, while attempting to provide more generic insights into multi-model integration for decision support in the environmental domain. Acknowledgements: This work was supported by the Blue Green Dream (BGD) Climate-KIC/EIT Project

Getting Hydroinformatic Tools From Research Into Practice: The Watershare Approach

The global Water Sector is faced with significant challenges, including, but not restricted to aging infrastructure, fluctuating populations, new pollutants, more stringent regulations and the need for benchmarking their performance. At the same time the Sector remains very fragmented and hence its R&D often doesn’t have the critical mass to develop the tools and models that are required. Although research institutes and academia do develop such tools, the road from the research environment to the first practical application often proves an insurmountable barrier. Watershare offers a platform for such a transition: Launched as an online placeholder for expert water-related tools, Watershare supports a closer collaboration between knowledge providers and knowledge consumers, within a quality assured environment. The Watershare concept encompasses a variety of benchmarked tools designed for areas like water quality and health, sustainability, water technology, asset design and management, and water systems. This paper briefly describes the main tools that are already in the toolbox and suggests possible gaps that need to be filled, matching them with key areas of concern in the water industry of tomorrow. The paper explains the way Watershare operates as a community of practice as well as one of collaborative research and knowledge co-creation. A knowledge management instrument that has been specifically designed to facilitate collective future visioning in an integrated and intelligent fashion is also presented and discussed. Synergies between the tools are explained and strategies supporting an organic, demand-driven, content creation addressing explicit needs of the Water Sector are outlined. It is suggested that this platform can act as a powerful vehicle to bring to market tools and innovation that has been up to date confined only to research prototypes while allowing for their application globally and providing Water Companies of different scales cost-effective access to high quality, benchmarked software tool

Enabling the uptake of circular water solutions

This study advances the discourse on the transition from a linear to a circular water paradigm, within which water is reused and resources such as nutrients and energy can be recovered. The research provides an empirical evidence from demonstrative cases, identifying the technological, economic, socio-cultural, and regulatory factors that facilitate or impede the broader adoption of circular solutions in the water sector. It proposes an integrated system approach, which encompasses a comprehensive set of enabling instruments, including (a) the demonstration of the sustainability of circular water technologies at a system level, thereby providing a robust proof of concept; (b) a shift from a conventional financial cost-benefit approach to a business model predicated on circular value chains, underscoring the economic feasibility of these solutions; (c) the enhancement of social acceptance through active stakeholder engagement, thereby fostering a supportive community for these transformative changes; and (d) the adaptation of the regulatory framework to incentivise circular water solutions, such as the establishment of dedicated end-of-waste criteria to facilitate market access for recovered resources. The study concludes that a concerted effort is required to reconceptualise our water systems as circular systems, and to legitimise the role of circular water within our society and economy

A glimpse into the euPOLIS multi-dimensional Indicator System for Site Screening & NBS Assessment

Evaluating the impact of Nature-Based Solutions (NBS) via appropriate indicators and metrics has attracted, in the past few years, significant interest. In response to this, the European Commission has recently published a handbook that aims to serve as a guide towards the evaluation of NBS impacts (EC, 2021) based on current available knowledge and state-of-art technologies and practices. The evaluation process, which involves the development and estimation of pertinent metrics, is crucial across the different NBS implementation stages, i.e., from the selection and design of effective NBS interventions to the NBS efficiency evaluation and potential improvement of the deployed systems. Within this context and as part of the work that was carried out for the euPOLIS project, an integrated indicator-based methodological framework is proposed herein for assessing the multi-dimensional aspects and impacts associated with the implementation of NBS in urban environments. The proposed framework employs different types of indicators with distinct functions and purposes and aims at providing structured guidance to practitioners and urban planners throughout all the different NBS analysis, deployment, and evaluation stages

SOURCE TO TAP URBAN WATER CYCLE MODELLING

This work was supported by TRUST (TRansitions to the Urban Water Services of Tomorrow) research project.The continuous expansion of urban areas is associated with increased water demand, both for domestic and non-domestic uses. To cover this additional demand, centralised infrastructure, such as water supply and distribution networks tend to become more and more complicated and are eventually over-extended with adverse effects on their reliability. To address this, there exist two main strategies: (a) Tools and algorithms are employed to optimise the operation of the external water supply system, in an effort to minimise risk of failure to cover the demand (either due to the limited availability of water resources or due to the limited capacity of the transmission system and treatment plants) and (b) demand management is employed to reduce the water demand per capita. Dedicated tools do exist to support the implementation of these two strategies separately. However, there is currently no tool capable of handling the complete urban water system, from source to tap, allowing for an investigation of these two strategies at the same time and thus exploring synergies between the two. This paper presents a new version of the UWOT model (Makropoulos et al., 2008), which adopts a metabolism modelling approach and is now capable of simulating the complete urban water cycle from source to tap and back again: the tool simulates the whole water supply network from the generation of demand at the household level to the water reservoirs and tracks wastewater generation from the household through the wastewater system and the treatment plants to the water bodies. UWOT functionality is demonstrated in the case of the water system of Athens and outputs are compared against the current operational tool used by the Water Company of Athens. Results are presented and discussed: The discussion highlights the conditions under which a single source-to-tap model is more advantageous than dedicated subsystem models.Rozos, E.; Makropoulos, C. (2013). SOURCE TO TAP URBAN WATER CYCLE MODELLING. Environmental Modelling & Software. 41:139-150. https://doi.org/10.1016/j.envsoft.2012.11.0151391504

From Smart Meters To Smart Decisions: Web-Based Support For The Water Efficient Household

Smart water metering technologies for residential buildings offer, in principle, great opportunities for sustainable urban water management. However, much of this potential is as yet unrealized. Despite that several ICT solutions have already been deployed aiming at optimum operations on the water utilities side (e.g. real time control for water networks, dynamic pump scheduling etc.), little work has been done to date on the consumer side. This paper presents a web-based platform targeting primarily the household end user. The platform enables consumers to monitor, on a real-time basis, the water demand of their household, providing feedback not only on the total water consumption and relevant costs but also on the efficiency (or otherwise) of specific indoor and outdoor uses. Targeting the reduction of consumption, the provided feedback is combined with notifications about possible leakages\bursts, and customised suggestions to improve the efficiency of existing household uses. It also enables various comparisons, with past consumption or even with that of similar households, aiming to motivate further the householder to become an active player in the water efficiency challenge. The issue of enhancing the platform’s functionality with energy timeseries is also discussed in view of recent advances in smart metering and the concept of “smart cities”. The paper presents a prototype of this web-based application and critically discusses first testing results and insights. It also presents the way in which the platform communicates with central databases, at the water utility level. It is suggested that such developments are closing the gap between technology availability and usefulness to end users and could help both the uptake of smart metering and awareness raising leading, potentially, to significant reductions of urban water consumption. The work has received funding from the European Union FP7 Programme through the iWIDGET Project, under grant agreement no318272

Best practices for Sustainable Urban Water Cycle Systems

Aging infrastructure, demographic change, water scarcity, pollution, climate change and other megatrends create the need for a transition towards more sustainable urban water cycle services (UWCS) in the cities. This report "Best practices for Sustainable Urban Water Cycle Systems - an overview of and enabling and constraining factors for a transition to sustainable UWCSs" deals with and reviews best practices in the water sector. It is divided in four different themes in UWCS which are: demand management, reuse and recycling, leakage and loss reduction and the water-energy nexus. The report bundles some of the worldwide experiences in applying technologies and approaches, that support a transition to more sustainable water cycle systems and that have proven to work on the ground. These experiences are presented as inspiration for water professionals who want to engage in activities that contribute to a more sustainable urban water cycle system.Makropoulos, C.; Rozos, E.; Bruaset, S.; Frijns, J.; Van Der Zouwen, M. (2014). Best practices for Sustainable Urban Water Cycle Systems. http://hdl.handle.net/10251/3572

Urban water system metabolism assessment using WaterMet2 model

This paper presents a new “WaterMet2” model for integrated modelling of an urban water system (UWS). The model is able to quantify the principal water flows and other main fluxes in the UWS. The UWS in WaterMet2 is characterised using four different spatial scales (indoor area, local area, subcatchment and system area) and a daily temporal resolution. The main subsystems in WaterMet2 include water supply, water demand, wastewater and cyclic water recovery. The WaterMet2 is demonstrated here through modelling of the urban water system of Oslo city in Norway. Given a fast population growth, WaterMet2 analyses a range of alternative intervention strategies including ‘business as usual’, addition of new water resources, increased rehabilitation rates and water demand schemes to improve the performance of the Oslo UWS. The resulting five intervention strategies were compared with respect to some major UWS performance profiles quantified by the WaterMet2 model and expert's opinions. The results demonstrate how an integrated modelling approach can assist planners in defining abetter intervention strategy in the future