THE WATER EFFICIENCY OF RETROFIT DUAL-FLUSH TOILETS: EXPERIENCE FROM SOUTHERN ENGLAND

In Water Resources Plan submissions to the Environment Agency in 1999, water companies predicted increases in demand over the next twenty-five years. With significant environmental and economic constraints on new resource developments, attention has focused upon the potential savings that water-efficiency measures can achieve.
The use of water for toilet flushing accounts for about 30% of household consumption, thereby offering considerable potential for water saving. The conversion of existing single-flush siphonic cisterns to dual-flush operation could be one method of achieving a desired reduction in water use, in accordance with the 'twin-track' approach to balancing supply and demand.
This small study, which was jointly funded by Southern Water and the Environment Agency, sought to measure the effectiveness of dual-flush toilets in reducing water consumption through an eight-month study of five retrofit devices which were installed in thirty-three unmetered domestic properties in West Sussex.     

洛惠渠灌区水量供需平衡分析

介绍了洛惠渠灌区的历年供需情况,结合该灌区的供需现状进行了供需平衡分析,研究了2015年的供需平衡,并针对性地提出了相应的对策建议,以缓解水资源供求矛盾,确保灌区社会经济的可持续发展。     

福州市水资源供需平衡的对策

水资源规划的核心是水资源平衡,水资源平衡是需求和供给的平衡,需水量预测包括工业、农业、城镇生活和河道生态需水量四个部分。通过分析用水统计数据,研究用水结构特点,进行需水量预测,提出水资源供需平衡规划及对策。     

土地开发整理中低压管灌的供需水量平衡分析

以河南某平原区土地开发整理工程的井灌区为例开展供需水量平衡分析,利用水文、地质、气象资料等,分别对项目区供水量、需水量进行测算分析,得到总供水量和需水量,从而对项目区供需水量进行平衡分析,得到项目管灌系统规划的区域有灌溉保证,不会引起地下水超采的结论。     

陕西省城市节水潜力分析

针对陕西省城市水资源供需不平衡且水资源浪费严重的现象,在分析了该省城市节约用水潜力的基础上,对城市节水方案进行了综合评估,提出了节约用水的基本方案与强化方案,以解决该省城市供需平衡的问题。     

Estimation of Outage Allowances

A methodology is described for estimating the allowances or safety margins which can be applied to estimates of water resources to allow for outages (random or periodic interruptions to supply). The methodology follows recent published UK Government and water-industry guidelines and provides estimates at two levels: on-average estimates, and risk-related estimates. Example applications are described, and advice is given on ways of improving the supply/demand balance. The final choice of any outage allowance to be used should take account of (a) patterns of demand, and (b) the consequences of failure.     

基于多源数据的成渝城市群绿色空间生态系统服务功能供需评价

随着城市规划逐步转向国土空间规划,准确掌握宏观尺度中的城市群绿色空间的服务特征成为规划决策的重要前提.基于多源数据,利用水量平衡方程、土壤流失方程、INVEST模型识别城市群绿色空间生态系统服务功能,利用Z-Score标准化评价生态系统服务功能供需平衡匹配的时空演变规律.结果显示:1)成渝城市群水源涵养服务供给、需求量...     

水生态系统服务供需视角下的水网乡村 适应性规划策略——以吴江张鸭荡片区为例

苏南乡村地区一直是中国乡村建设的先行区域,特殊的纵横交错的水网结构构成了一个错综复杂的系统,呈现出其他地区不具有的复杂性和生态特殊性。随着城镇的扩张,乡村的发展建设使其水网空间的平衡发展面临极大的挑战。传统单一静态的规划方法逐渐显示出无法适应经济、社会等发展要求的缺陷。苏南乡村地区以水为核心,从水生态系统服务供需关系的视角下探究水网乡村的适应性规划策略更加适应当前的乡村现状和需求。以传统水网乡村空间形态转译为基础,建立水生态系统供需服务评估体系,在评估水生态系统服务供需能力的基础上,分析供需分异模式及供需矛盾。从构建乡村水域空间生态格局、乡村水域空间功能分区规划,以及乡村水域空间多情景预判3个方面,提出苏南水网乡村的适应性规划策略,并为水网乡村的生态实践提出新思路。     

平衡还是匹配？生态智慧引导下的公园 绿地供需关系多情景分析与优化

城市公园绿地生态系统服务供需关系的量化研究能够反映城市中的人地关系,对提升公园公平性和市民福祉至关重要。在生态智慧的引领下对公园绿地供需关系进行思考,认为公园绿地供需关系需要从生态系统服务供需平衡转向供需匹配,同时需要考虑生态系统服务需求的多样性和差异性。在公园绿地生态系统服务供需测度和供需关系分析的基础上,提出构建基于多情景规划的供需匹配研究与优化的逻辑框架与实践路径。以上海市杨浦区为例,对公园绿地供需情况进行了基于经济发展、社会公平、社会正义和综合协调等导向下的多情景规划模拟和比较分析。最后,综合上述情景中出现的问题提出优化方案和提升策略来实现"供需动态匹配"的目标。     

公园城市目标下城市绿地系统建设的 国际经验：基于英国伦敦实践研究

"公园城市"理念的提出开启了新时代中国城市绿地发展的新篇章,适应了人民对美好生活的需求。当前,在我国资源约束趋紧、环境污染严重、生态系统退化的严峻形势之下,城市绿地系统结构优化、管控革新和内在进级面临全新挑战,亟待探索公园城市目标下的中国城市绿地系统新型发展模式与可持续优化路径。工业革命后,英国伦敦城市绿地系统历经百年发展,完善的绿色框架受到全球广泛推崇。在系统梳理英国伦敦城市绿地系统发展历程的基础上,从政策框架、建设实施、信息共享、绩效评价、后续管理、运营参与等方面重点阐述其在我国城市绿地系统建设方面的特色亮点和成功经验。对标当前我国城市绿地系统建设面临的问题与需求,从战略指引的顶层设计、问题导向的功能响应、数字支撑的管控平台、多方协同的建设实施、灵活多样的运营模式5个方面有针对性地提出我国城市绿地系统优化建设路径,进而为我国"公园城市"目标下的城市绿地系统的科学建设提供参考借鉴与发展指引。     

The water supply is fine: decision‐maker perceptions of water quantity and supply‐side management

Years of research have called for more science to be integrated into water management decisions and for a shift from supply‐side to demand‐side management; yet, there remains a strong emphasis on supply‐side approaches and in many areas limited attention to hydrological data. A survey and interviews with decision‐makers in western North Carolina reveal that there is only low‐level concern about water quantity, and this drives a continued emphasis on supply‐side management and no perceived need for hydrological data. The historical realities of low demand and abundant water have generated a perception of ‘water supply’ as disconnected from physical, hydrological systems and allowed for ad hoc decision‐making processes to prevail. The lack of well‐established processes may, ironically, provide significant opportunities for employing collaboration among researchers and decision‐makers to develop policies and processes that integrate data into making water management decisions and thus prompt increased attention to water demand.     

住宅生活给水管网水力计算程序设计

根据住宅建筑给水管网的水流特点及其水头损失计算公式 ,确定了采用有限元法分析住宅建筑给水管网水力平衡计算的数学模型 ,将各个管段的单元矩阵方程集合为供水管网的整体矩阵方程 ,通过引入节点水压边界条件并求解管网整体矩阵方程——对称正定线性方程组 ,得出各项水力要素。给出了计算程序框图 ,编写了通用电算程序 ,经实例计算表明 ,能够快捷准确地完成住宅建筑给水管网的水力平衡计算 ,满足设计计算要求。     

‘Reaching the Parts Other Grants Don't Go?’ Supporting Self-provided Housing in Rural Scotland

Ensuring that rural areas of the UK have sufficient affordable houses in reasonable condition has long challenged policy makers. Previous research shows that rural housing has demand characteristics and faces supply constraints that have proven difficult to balance. The paper reports on the reasons why an innovative subsidy has achieved some success in overcoming barriers to provision in rural Scotland. It is argued that the subsidy has boosted effective demand and tackled a major supply constraint, namely land availability. Empirical material is drawn from a systematic evaluation of the mechanism. The paper concludes with reflections on its implications for the wider literature and for rural housing provision in the evolving financial and political context.     

基于重要性——绩效表现分析的上海苏州河滨水空间文化性生态系统服务供需关系分析与优化

生态系统服务的研究正经历着从解析机理到供需匹配的侧重点迁移，研究指出文化性生态系统服务的供需特征表现为4个方面：1）受服务人群的影响；2）兼具非排他性与潜在竞争性；3）各类型之间具有明显的融合性；4）与空间要素密切相关。针对已有的研究存在供需关联薄弱和整体评测不足的短板，研究以场地尺度的城市滨水空间为对象，提出重要性—绩效表现分析（Importance-Performance Analysis，简称IPA）可以成为测度和分析文化性生态系统服务供需状况的有效方法。选取上海苏州河4处滨水空间，从景观要素特征因子识别出发，基于IPA构建特征因子的重要性—满意度分布模型，分析滨水空间文化性生态系统服务供需特征，通过对需求的回应，明确优化有效服务供给的策略，从而为城市滨水空间存量更新与规划设计提供可行有效的技术支持以及可操作、可落地的决策依据。     

A decision support tool for sustainable planning of urban water systems: Presenting the Dynamic Urban Water Simulation Model

Population growth, urbanisation and climate change represent significant pressures on urban water resources, requiring water managers to consider a wider array of management options that account for economic, social and environmental factors. The Dynamic Urban Water Simulation Model (DUWSiM) developed in this study links urban water balance concepts with the land use dynamics model MOLAND and the climate model LARS-WG, providing a platform for long term planning of urban water supply and water demand by analysing the effects of urbanisation scenarios and climatic changes on the urban water cycle. Based on potential urbanisation scenarios and their effects on a city's water cycle, DUWSiM provides the functionality for assessing the feasibility of centralised and decentralised water supply and water demand management options based on forecasted water demand, stormwater and wastewater generation, whole life cost and energy and potential for water recycling. DUWSiM has been tested using data from Dublin, the capital of Ireland, and it has been shown that the model is able to satisfactorily predict water demand and stormwater runoff.     

Evaluating the effects of climate change on the water resources for the city of Birmingham,UK

Climate change is expected to affect precipitation patterns and may therefore impact upon water resource availability. The city of Birmingham in central England receives its public water supply from a catchment in the Elan Valley, mid‐Wales. Baseline and future climate projections generated from a stochastic weather generator within the United Kingdom Climate Projections 2009 and a daily soil water balance model (WaSim) were used to determine the potential impacts of climate change on hydrologically effective rainfall (HER). Annual HER is likely to decrease from baseline conditions (> 90% likelihood that HER will be reduced), with more frequent and persistent very dry spells and increasing seasonality. It is concluded that climate change will put additional stress on water resources for the city of Birmingham so that, coupled with expected increases in demand, adaptation measures to increase supply and/or reduce demand are likely to be needed.     

住宅给水系统中按户计收水费技术探讨

针对目前自来水公司“抄总表计费，居民按每户装设的分表分摊水费”的收费方式，已不能适应每户居民按实际用水量付费要求的现状，介绍了设计，管理体制，经济核算等诸多方面的情况，从技术方面，分析了旧住宅给水系统在运行中的弊端，从而提出改进管道系统设计在每户装表，远程抄表等方面按户计收水费的技术措施。     

多管材给水管网水力计算的探讨

根据多管材给水管网的水流特点及其水头损失计算公式 ,确定了给水管网沿线流量折算节点流量的折算系数的取值 ,应用有限元法分析多管材供水管网的水力平衡计算数学模型 ,由各个管段的水力平衡单元矩阵方程集合为给水管网水力平衡的整体矩阵方程 ,通过引入节点水压边界条件并迭代求解管网水力平衡整体矩阵方程——对称正定线性方程组 ,得出各项水力要素。给出了计算程序框图 ,编写了通用电算程序 ,经实例计算表明 ,能够快捷准确地完成多管材给水管网的水力平衡计算 ,满足设计计算要求     

基于网格尺度的公园绿地供需时空差异——以哈尔滨主城区为例

城市快速发展可能引发公园绿地供需关系偏离规划目标,导致其供需矛盾日益加重。为探索公园绿地供需差异并解决供需研究尺度的局限性,以500 m×500 m网格为基础研究单元,以公园绿地分级设置要求为阈值,采用高斯两步移动搜索(Ga2SFCA)法和供需水平测度方法分别分析2010、2018年哈尔滨主城区公园绿地可达性时空分布变化和供需时空差异。研究表明,哈尔滨主城区公园绿地供给水平未达城市绿地规划标准要求,尽管公园绿地面积增多,但不合理的空间配置反而加剧了公园绿地供需失衡,不同区域间公园绿地种类的不均衡性是引起供需空间差异的关键。经进一步推测,建设时期、土地资源、城市规划和市场机制是公园绿地供需差异的主要影响因素。根据供需匹配结果,提出针对性的公园绿地布局优化策略,为公园绿地供需平衡提供精细有效的参考依据。     

Stochastic modelling of water demand by domestic washrooms in residential tower blocks

Accurate estimates of probable simultaneous maximum demand are essential for appropriate decisions on sizing water supply plants and piping systems for high-rise residential buildings at a balance of acceptable plant reliability and construction cost. This study proposes a stochastic model of the probable maximum simultaneous water demands of domestic washrooms at some usage patterns for which the appliances in the same washroom would not operate simultaneously. The model parameters were determined from surveys of usage patterns in 597 domestic washrooms of typical high-rise residential buildings in Hong Kong. The results showed that the probable maximum simultaneous demands due to a number of domestic washrooms in a typical high-rise residential building were only about 50–60% of those estimates with an assumption of all appliances in simultaneous operation. This study is a useful source of reference in determining loadings of water supply plants and piping systems for high-rise residential buildings.