Benchmarking the Effects of Water Demand Management During Water Crisis in a Regional City.

Regional cities are having their unique water security challenges due to regional urban water contexts, regional socio-economic structure, and climate conditions. Regional urban community's perceptions of water usage are expected to be different from the communities in large metropolitan cities. The city of Townsville is the largest regional city in the northern tropical region of the state of Queensland in Australia, and it is known to have its unique dry tropic climate condition. The city faced a water crisis due to a prolonged drought in 2013-2018. As part of this research, at first, a literature review was conducted to understand what water demand management (WDM) tools worked well during urban water crisis in different parts of the world. This paper then investigates how residential water usage changed with the changes in drought measures in the city of Townsville in the last decade. A minimum per capita residential water requirement is established for the study region to benchmark the effects of tools implemented in the region. The paper investigates the WDM policies implemented in the city of Townsville including when the policies were applied and the impacts and efficacy of these policies before water crisis, during water crisis and after water crisis. The most effective WDM tools identified are water restrictions, public awareness raising and education programmes. The impacts of water restriction policies and the perceptions of local water professionals on their success elements are also studied. The results are compared and the reasons behind the findings are investigated.

Determinants of Landscape Irrigation Water Use in Florida-Friendly Yards.

Efforts to mitigate outdoor water use in Florida's urban landscapes increasingly include promotion of regionally appropriate landscaping based on its documented effectiveness. Targeted initiatives, however, require an understanding of mechanisms underpinning low irrigation use in single-family homes with Florida-Friendly Landscaping (FFL). This paper reports survey research conducted in southwest Florida to identify factors associated with irrigation practices among FFL clients. Results indicate that approximately half of survey participants irrigated less frequently than once per week year-round. Aesthetic considerations, horticultural knowledge, and membership in a homeowner's association (HOA) with rules regarding yard care were key variables underlying landscape characteristics and maintenance, while property values, water conservation attitudes, lawn grass, and in-ground irrigation system use significantly predicted irrigation practices. Homes with in-ground irrigation systems were more than six times more likely to water their landscapes at least once per week during the warm season when residential outdoor water use is at its peak. A $100,000 increase in a home's market value increased the odds of weekly watering by a multiplicative factor of two, whereas a one-point increase in a six-item Likert scale used to measure a homeowner's water conservation attitude decreased the odds by 76%. Homes with no grass in the landscape were 71% less likely to water on a weekly basis. Providing homeowners, and HOAs, with educational resources that build on existing support for water conservation could augment adoption of low maintenance plants and sustainable practices in Florida's urban landscapes.

Enhancing domestic water conservation behaviour: A review of empirical studies on influencing tactics.

The world faces imminent drought-related challenges that, from a tap-water supply perspective, require increasingly expensive infrastructure enhancement and energy expansion to maintain sufficient service levels. This paper argues that enhancing domestic water conservation provides a promising alternative or necessary addition to reduce costs and to stimulate pro-environmental behaviour. Although the number of field experiments on how people's behaviour can be changed with respect to their daily water consumption is growing, to date, most studies in this field have focussed either on explanatory socio-economic factors (e.g. water pricing, income, or family composition) or behavioural intentions and personal characteristics related to behavioural change. Accordingly, there is limited empirically validated knowledge about the use and effectiveness of different influencing tactics to change behaviour. This paper provides a review of the empirically oriented literature in this field and aims to provide an up-to-date assessment that identifies eight different Behavioural Influencing Tactics (BITs) that target long-term water conservation behaviour within households. Our analysis is structured around three information processing routes: the reflective route, the semi-reflective route, and the automatic route. We conclude that the current body of literature is promising and provides a useful body of evidence on the range and effectiveness of individual water conservation mechanisms, but that needs further development to deepen our understanding of how to effectively prolong and reinforce newly formed water conservation routines.

Evaluating a novel tiered scarcity adjusted water budget and pricing structure using a holistic systems modelling approach.

Population growth, coupled with declining water availability and changes in climatic conditions underline the need for sustainable and responsive water management instruments. Supply augmentation and demand management are the two main strategies used by water utilities. Water demand management has long been acknowledged as a least-cost strategy to maintain water security. This can be achieved in a variety of ways, including: i) educating consumers to limit their water use; ii) imposing restrictions/penalties; iii) using smart and/or efficient technologies; and iv) pricing mechanisms. Changing water consumption behaviours through pricing or restrictions is challenging as it introduces more social and political issues into the already complex water resources management process. This paper employs a participatory systems modelling approach for: (1) evaluating various forms of a proposed tiered scarcity adjusted water budget and pricing structure, and (2) comparing scenario outcomes against the traditional restriction policy regime. System dynamics modelling was applied since it can explicitly account for the feedbacks, interdependencies, and non-linear relations that inherently characterise the water tariff (price)-demand-revenue system. A combination of empirical water use data, billing data and customer feedback on future projected water bills facilitated the assessment of the suitability and likelihood of the adoption of scarcity-driven tariff options for a medium-sized city within Queensland, Australia. Results showed that the tiered scarcity adjusted water budget and pricing structure presented was preferable to restrictions since it could maintain water security more equitably with the lowest overall long-run marginal cost.

Impact of water management practice scenarios on wastewater flow and contaminant concentration.

Due to frequent droughts and rapid population growth in urban areas, the adoption of practices to reduce the usage of fresh water is on the rise. Reduction in usage of fresh water can be achieved through various local water management practices (WMP) such as Water Demand Management (WDM) and use of alternative water sources such as Greywater Recycling (GR) and Rainwater Harvesting (RH). While the positive effects of WMPs have been widely acknowledged, the implementation of WMPs is also likely to lower the wastewater flow and increase the concentration of contaminants in sewage. These in turn can lead to increases in sewer problems such as odour and corrosion. This paper analyses impacts of various WMP scenarios on wastewater flow and contaminant load. The Urban Volume and Quality (UVQ) model was used to simulate wastewater flow and the associated wastewater contaminants from different WMP scenarios. The wastewater parameters investigated were those which influence odour and corrosion problems in sewerage networks due to the formation of hydrogen sulphide. These parameters are: chemical oxygen demand (COD), nitrate (NO3(-)), sulphate (SO4(2-)), sulphide (S(2-)) and iron (Fe) that were contributed by the households (not including the biochemical process in sewer pipe). The results will help to quantify the impact of WMP scenarios on odour and corrosion in sewerage pipe networks. Results show that the implementation of a combination of WDM and GR had highly increased the concentration of all selected contaminant that triggered the formation of hydrogen sulphide, namely COD, sulphate and sulphide. On the other hand, the RH scenario had the least increase in the concentration of the contaminants, except iron concentrations. The increase in iron concentrations is actually beneficial because it inhibits the formation of hydrogen sulphide.

Public perceptions of physical and virtual water in China.

Ensuring access to water is one of the United Nations' Sustainable Development Goals. Water demand management, which has emerged as an important approach to secure water supply, should be underpinned by a good understanding of how the public perceive their use of water. In this study, we investigated public perceptions of physical and virtual water in China through online surveys using the multi-level regression models (two-level models). Based on 3262 responses, we found that overall, participants underestimated water uses and differences between water uses (daily potable water of an adult, shower, toilet flushing, etc.). Most participants did not possess the knowledge of virtual water embedded in their daily consumed products. Individuals showed rather different perceptions in water use, which were affected by gender, age, education, resource and environmental attitude, water saving behaviors, water price and residential water source. In combination with previous findings in the United States, we concluded that despite different natural water endowment and socio-economic and cultural conditions, underestimation of water use is commonly shared by Chinese and Americans. This highlights a need of strengthening public knowledge of water use. The results are useful in informing policies to enhance the public's awareness of water use towards improved water demand management.

Sustainable management of water demand using fuzzy inference system: a case study of Kenyir Lake, Malaysia.

Sustainable water demand management has become a necessity to the world since the immensely growing population and development have caused water deficit and groundwater depletion. This study aims to overcome water deficit by analyzing water demand at Kenyir Lake, Terengganu, using a fuzzy inference system (FIS). The analysis is widened by comparing FIS with the multiple linear regression (MLR) method. FIS applied as an analysis tool provides good generalization capability for optimum solutions and utilizes human behavior influenced by expert knowledge in water resources management for fuzzy rules specified in the system, whereas MLR can simultaneously adjust and compare several variables as per the needs of the study. The water demand dataset of Kenyir Lake was analyzed using FIS and MLR, resulting in total forecasted water consumptions at Kenyir Lake of 2314.38 m3 and 1358.22 m3, respectively. It is confirmed that both techniques converge close to the actual water consumption of 1249.98 m3. MLR showed the accuracy of the water demand values with smaller forecasted errors to be higher than FIS did. To attain sustainable water demand management, the techniques used can be examined extensively by researchers, educators, and learners by adding more variables, which will provide more anticipated outcomes.

O Programa AGUAPURA de racionalização do consumo de água da Universidade Federal da Bahia / The AGUAPURA Program for water consumption rationalization at the Federal University of Bahia

RESUMO Este artigo descreve e discute os métodos usados, as dificuldades encontradas e os resultados obtidos em um programa de racionalização do uso da água desenvolvido por um programa de pesquisa da Universidade Federal da Bahia. Na universidade, foi alcançada redução de até 49% no consumo per capita. No aeroporto e em um shopping center de Salvador foram identificados cenários de reduções ainda maiores. Pesquisa de opinião justifica a admissão de alternativas inovadoras de grande impacto. Em um conjunto de prédios do Governo do Estado da Bahia as reduções atingiram 55, 72 e 82% nos três prédios mais comprometidos com o projeto. Os resultados obtidos levaram o Governo do Estado a estender o projeto a todos os seus prédios administrativos e às escolas públicas estaduais.

ABSTRACT This article describes and discusses methods, results obtained and difficulties found in a water-use rationalization program developed by a research program at the Federal University of Bahia. At the University we obtained a reduction of up to 49% in per capita consumption. At the airport and in a shopping center in Salvador we identified other scenarios for further reductions. Opinion survey justifies the admission of innovating high-impact alternatives. In a set of buildings of the State Government of Bahia, reductions reached 55, 72 and 82% in the three buildings most committed to the project. The results led the State Government to extend the project to all its administrative buildings and public schools.

Integrando a modelagem da alocação de água ao sistema de indicadores FPEIR: aplicação ao semiárido do Brasil / Integrating water allocation modelling into the DPSIR Indicator System: application to the semi-arid region of Brazil

RESUMO Este estudo propõe uma abordagem combinada do modelo força motriz-pressão-estado-impacto-resposta (FPEIR) com a modelagem de alocação de água para avaliar as estratégias de gerenciamento da demanda hídrica na bacia hidrográfica do rio Apodi-Mossoró (RN). O crescimento populacional aliado ao desenvolvimento econômico, a inadequada gestão e as mudanças climáticas são as forças motrizes para a escassez hídrica e os conflitos do sistema hídrico em análise. O Sistema Integrado de Gerenciamento dos Recursos Hídricos do estado é responsável pela gestão da bacia em foco. Os instrumentos da Política Nacional dos Recursos Hídricos (definidos pela Lei nº 9.433/97) encontram-se parcialmente implementados na bacia. A Companhia de Águas e Esgoto do Rio Grande do Norte (CAERN) projeta a ampliação do sistema hídrico. Nesta pesquisa, o sistema Apodi-Mossoró foi analisado frente a quatro estratégias de alocação e variações nas condições requeridas para os seus reservatórios. A análise realizada mostra falhas no atendimento às demandas do sistema, as quais poderão ser amenizadas nas estratégias que incorporam a gestão da demanda de água e o aporte das águas da transposição do Rio São Francisco. Os resultados permitem sugerir medidas adaptativas de economia de água, incluindo o seu reúso, como opções para um melhor planejamento e gerenciamento dos recursos hídricos da bacia.

ABSTRACT This study proposes a combined approach of the DPSIR (Driving forces-Pressures-State-Impact-Response) model with water allocation modeling to evaluate water demand management strategies in the Apodi-Mossoró River Basin (Rio Grande do Norte, Brazil). Population growth coupled with economic development, inadequate management and climate changes are the driving forces for water scarcity and the conflicts of under analysis here. The State's Integrated Water Resources Management System is responsible for managing the basin in focus. The instruments of the National Water Resources Policy (defined by Law 9.433/97) are partially implemented in the basin. The Water and Sewage Company of Rio Grande do Norte projects the expansion of the water system. In this research, the Apodi-Mossoró System was analyzed considering four allocation strategies and variations in the conditions required for its reservoirs. The analysis shows failures in meeting the demands of the system, which can be mitigated through strategies that incorporate water demand management and water transfers from the São Francisco River Basin. The outcomes suggest adaptive water saving measures, including water reuse, as options for better water planning and management in the basin.