Context driven policy design in urban water management. A case study of Windhoek,Namibia

Urban water management in the southern cities of Namibia is composed through both a formal and an informal system. In the formal system, controlling demand is the key issue, and in the informal system, an improved accessibility to water is fundamental. The main issue raised in this paper is how authorities can support an ever-increasing poor population with water and at the same time keep demand among households with private water connections at a reasonable level. To decrease the demand for water in Windhoek, a thorough water demand management strategy (WDM) was launched in 1994. Water managers showed a high level of adaptability to the alarming water situation. One of the lessons learned from the implementation in Windhoek is that dedicated people with active involvement and vision are important for successful WDM. The budget must be allocated on a continuous basis for the implementation of certain WDM measures and a degree of flexibility among water users is important for the strategy to be successful. The dual situation experienced in cities in the South where both a need to expand services, and at the same time control demand, calls for a new approach in urban water management. Strategies need to be socially specific and flexible to changing pre-conditions. Therefore, a context driven policy design is advocated.     

青岛市城市交通需求管理策略研究

介绍了国内外交通需求管理(TDM)研究的发展过程和国外成功的TDM经验,针对青岛市目前城市交通存在的问题和特点,提出了实施有关TDM策略的一些初步看法,初步探讨青岛市在交通建设方面可以采取或调整的管理措施和策略,尤其是围绕目前重点建设的城市公共交通优先策略和先进的交通控制和管理措施等方面进行了分析和建议.     

Water demand management: implementation principles and indicative case studies

Current practices for the efficient use and management of water resources are based on the conjunctive application of water supply and demand measures. Even though options for the augmentation of water supply are widely analysed and assessed, water demand management remains an open field for study, as it is highly dependent on the socio‐economic features of a region and has a site‐specific character. This paper summarizes the guiding principles of demand management and presents some successful application examples of demand management measures from regions that cover a wide range of socioeconomic and environmental conditions in an effort to identify the critical factors for the efficient planning and implementation of demand management plans.     

Exploration of domestic water demand attitudes using qualitative and quantitative social research methods

The sustainable evolution of the urban water system requires the recognition of uncertainty embedded in both climate and human behaviour. A challenge that water managers and policy makers need to tackle, is to understand the way the society’s water demand behaviour is affected. The inaccuracy between attitudes and behaviours and the cognitive association of water use to living standards, hinders the projection of society’s response to management’s measures. Thus, it is necessary to identify leverage points, where water demand management policies should aim their efforts. This work presents two parts of a social research held in Athens: quantitative questionnaire gathering information regarding the domestic water demand attitudes and behaviours; and a series of qualitative interviews aimed at exploring in-depth, the domestic water use attitudes, and behaviours. This work presents the design and results of both methods and the combination of the quantitative results with insights from the qualitative work.     

Comparing the utility of LiDAR data vs. multi-spectral imagery for parcel scale water demand modeling

In this paper we examine whether land-cover measures derived from multi-spectral (MS) imagery in combination with light detection and ranging (LiDAR) data sources better predict parcel scale urban water consumption than measures derived solely from MS imagery. Land-cover measures such as the percentage of impervious surface and vegetative cover are important predictors of household level water use. This study found that the additional effort required to obtain LiDAR data does not appear to add predictive power for water demand modeling. We suggest that MS imagery is just as useful estimating household level water demand.     

Water resources management in the Jordan River Basin

The Jordan River Basin is under great hydric stress. Increases in population and agricultural demand are contributing to the closure of the basin. This paper analyses the results of integrated water resources planning model (WEAP) by studying the vulnerability of water resources in the lower Jordan River under a changing climate pattern and growing water demands. Water balance models show that all aquifers supplying the city of Amman will be depleted within the next few decades. Mitigation measures should include the introduction of additional water into the basin through the Red Sea–Dead Sea canal, in addition to demand management measures such as water conservation and increase in irrigation efficiency. The findings of this study would provide a useful guide to the co‐riparians for policy formulation, decision making and dispute resolution. Cooperation among the five riparian countries may be improved by building a Geographic Information System (GIS) database that provides access to accurate data for hydrological analysis.     

城市交通需求管理的国际借鉴与策略建议

交通需求管理是解决当前我国城市交通拥堵与高碳排放问题的当务之急。城市交通需求管理的根本理念是引导人们采取科学的交通行为、理智地使用道路交通设施及其有限资源。结合各国的实践,城市交通需求管理的主要策略有:坚持公交优先、引导小汽车合理使用、发展自行车交通、土地使用与交通用地联合规划、推行步行化模式等。     

大城市交通需求管理研究

首先对交通需求管理产生背景、涵义与目的及发展概况进行介绍 ;然后提出实施交通需求管理措施所应遵循的公平合理的原则、经济与环境可持续发展的原则、优先发展公共交通的原则、道路时空资源均衡使用的原则、多方结合协调发展的原则、坚持因地制宜经济适用的原则、社会可接受原则 7条主要原则 ;最后根据城市交通需求管理所涉及的问题 ,将交通需求管理划分为四个层次 ,在此基础上进一步对城市交通需求管理措施进行探讨     

A sustainable framework for water resources management in an urban watershed: the case of Volos,Greece

The implementation of sustainable development principles in water resources management refers to an integrated management and coordination of the entirety of the actions and interventions that concern the water ecosystem, or parts of it, within a watershed. This procedure is accomplished through the development and application of an overall management plan at a hydrological basin level. This concept was followed by the water resources management plan of the city of Volos' watershed, which is presented in this paper. The main objective is the choice of the best set, among others, of hydraulic projects, which will be able to re-establish the balance in the basin's deficient water budget, satisfying at the same time future urban water demand. Decision making was carried out using a GIS tool and involved traditional water capture hydraulic projects on the one hand and sustainable water saving measures on the other. The whole procedure is being developed in an area with serious environmental problems, concerning mainly the groundwater resources. The particularity here is that the alternative solutions strongly depend on administrative agreement and consensus between relevant authorities.     

Water conservation potential in educational institutions in developing countries: case study of a university campus in Ghana

This paper presents evidence of the potential for institutional water conservation in a developing country using a university campus in Kumasi, Ghana, as a case study and suggests measures for reducing water demand in institutions. A water end-use survey was conducted using a sample of 144 students from six halls of residence to determine lavatory faucet (tap), showerhead and water closet water-use. The average per capita water use was 115.12 ± 5.33 litres per day at 95% confidence level. Results of the water end-use analysis showed that students use high quantities of water for bathing (61.90 ± 4.06 litres per capita per day at 95% confidence level). There is a potential for reducing the annual water demand by 30.85% through water conservation measures such as retrofitting with water-efficient showerheads and water closets. The payback period for the cost of retrofitting in the current study was found to be 6.5 years.     

河北省城市用水的健康循环与需求管理

分析了河北省城市用水、供水历年统计数据，结果表明，实施需水管理不仅可以减少水的社会循环规模，而且可以合理地预测未来城市用水需求，指导政府科学决策水工业设施政策；在河北省完全可取缔自备水井，这不仅有利于发挥公共供水企业规模效益，而且有利于实现水资源的持续开发利用。     

基于需求导向的中小城市地下空间规划

以丹阳市为例,研究了中小城市地下空间开发利用的条件与需求,探讨了基于需求导向的中小城市地下空间开发利用规划方法。该方法以地下空间资源评估与需求预测为基础,综合考虑城市自然及社会经济条件,结合地面城市规划,对规划区的地下空间开发利用供需情况进行了对比分析,针对城市发展与空间的供需矛盾,提出了合理的地下空间开发策略、规模和布局方案,使地下空间的利用功能与地面城市规划相协调,以改善地面交通矛盾和用地紧张等问题。对重点地区提出相应的规划指引,给出地下空间开发利用指标,使规划具有较强的可操作性,以便于规划目标的落实。     

Artificial shortage of surface water: how can water demand management mitigate the scarcity problem?

Water demand management stresses the crucial roles of water user motivations in balancing actual water availability and competing human needs. This paper shows how the absence of such motivations influences artificial water scarcity, even in resource‐abundant countries, and how slight modifications to economic instruments (surface water charges in particular) might solve the problem. Data from the Czech Republic are used to illustrate the rationale behind the artificial scarcity problem and its solution. A model with feedback based on historical surface water abstraction data is built to simulate the impacts of different payment modification scenarios.     

Designing and calibrating an agent-based platform to evaluate the effect of climate variables on residential water demand

Many Iranian metropolises, including Shiraz, are situated in arid and semi-arid regions, lacking sufficient renewable water resources. In recent years, climate changes, including drought and rising temperatures, have led to changes in water supply and demand. Given the necessity and importance of urban water supply, this study investigates the impact of different climate scenarios on residential water demand. Many studies, in their models, do not consider the social interactions between household water consumers and the change in their consumption behaviour, which serves as a fundamental drawback. Thus, the present research attempts to propose an agent-based framework by modelling social interactions via the diffusion process to investigate water consumption behaviour efficiently. The model is calibrated and applied to Shiraz City in Iran, according to the data from 2006 to 2019, and it is used to simulate each scenario for the following years until 2032. The findings show that temperature has a positive and significant effect on residential water consumption; yet, rainfall negatively affects water consumption. The simulation results of these scenarios for temperature increase or decrease and rainfall changes are estimated. In addition, the developed agent-based platform can be easily calibrated and adjusted based on the data of any other city to simulate water demand estimation under different climatic and even economic scenarios. Urban water managers can benefit from such estimates to plan future infrastructure development and proactive management of seasonal water resources under the growing pressure of potential climate change because construing the sensitivity of seasonal water consumption to climate conditions is essential to respond to variations in demand.     

Managing Water Services Through Service Differentiation and Pricing in an African City

A key challenge for managers of water utilities in developing countries is to provide services to the rising urban population in a financially sustainable manner. The paper examines the management of water services in an African city which piloted service differentiation and pricing. Among the key findings was that substantial improvement in the provision of water services to the urban poor was attained. Cost recovery was achieved through innovative structuring of public/private partnerships, an appropriate pricing policy, and flexible payment systems. The project demonstrates that (a) by structuring service delivery with appropriate pricing, utilities could serve more customers (including people living in informal settlements) at affordable cost and achieve financial sustainability, and (b) service differentiation and appropriate pricing has the potential to improve urban water services in low-income countries.     

Domestic wastewater management in South and Southeast Asia: the potential benefits of a decentralised approach

Owing to its enormous construction and maintenance costs, the management of wastewater in many urban centres of developing countries via a centralised wastewater management approach is very difficult. Often, untreated wastewater is directly discharged into adjacent natural water courses, causing a grave threat to both public health and the aquatic environment. A decentralised wastewater management approach is a prospective solution to overcome this adverse situation because of its low cost, simple operation and revenue return. To identify the potential of a decentralised wastewater management system in developing countries, the wastewater management policies, institutional frameworks, reuse practices and sanitation situations in selected Asian countries were reviewed and recommendations for effective wastewater management are proposed.     

Transition to a water-cycle city: sociodemographic influences on Australian urban water practitioners' risk perceptions towards alternative water systems

Transition to a sustainable water future such as the water-cycle city will necessitate shared, diversified risk management, which acknowledges the subjective risk perceptions of all stakeholders, including water practitioners. Such risk perceptions might vary with personal and professional characteristics. This study explores the influence of these characteristics on Australian urban water practitioners' risk perceptions of four alternative water systems, varying in scale of operation and water source, i.e. seawater desalination, indirect potable reuse, sewer mining and stormwater harvesting systems. Analysis of sociodemographic and risk perception data (N = 620) collected from a national online survey revealed that risk perceptions can vary with age or number of years' experience, educational qualification, stakeholder group and area of work within the water sector, reflecting different communities of practice. To facilitate adoption of a suite of sustainable urban water systems, these different risk perceptions must be identified, acknowledged and managed. Targeted social learning through experimentation is a useful approach to achieve this.     

Estimating irrigation water demand for green spaces in humid areas: seeking a sustainable water management strategy

Quantifying the irrigation water demand of green spaces (IWDG) is an important part of smart urban water management. However, the IWDG in humid cites is not well characterized. Moreover, the alteration of natural hydrological processes caused by urbanization leading to the dependence of green spaces on irrigation is becoming more common. To better understand the IWDG in humid areas, we developed an estimation model and used the Yangtze River Delta in China as a case study. Results showed that the amount of water required by the green spaces in the Yangtze River Delta was approximately 354 × 10⁶ m³, which was equivalent to 12% of the urban residential water consumption in 2011. This study also investigated the spatial-temporal changes of urban green spaces and estimated their effects on irrigation water demand. These findings provide policymakers an integrated view of the water demand of green spaces associated with sustainable management.     

运输需求管理的思想、方法及实施的基本内容

运输需求管理 (TDM )在发达国家已得到重视并开始实施 ,并成为解决目前交通问题的有效措施 ,我国存在同样的交通问题 ,需要引入TDM管理思想 .介绍了国外采取的措施及取得的成果 ,提出了我国TDM的措施和引入TDM思想的初步做法 .     

城市化进程中水资源供需趋势分析

在阐述我国城市化发展特点及现状的基础上，从总用水量、用水结构及用水设施的变化几个方面，探讨了我国总体水资源供需变化趋势及城市用水量总体变化趋势，为进一步制定城市水资源规划及管理政策提供借鉴。