A Desktop Analysis of Potable Water Savings from Internally Plumbed Rainwater Tanks in South-East Queensland,Australia

A methodology for the estimation of household potable water saving due to internally plumbed rainwater tanks (IPT) is presented in this paper. The methodology is based on a pairwise comparison of household water billing data between homes with IPT and without rainwater tanks (No Tank). These savings were compared with estimations using measured end use data and rainwater demand predictions using the Rainwater TANK model. The paper describes the application of this methodology to a case study in the south-east Queensland (SEQ) region of Australia. There was a significant reduction in mains water consumption for IPT properties in all regions studied in SEQ. Water reductions from mains supplies varied markedly across regions with mean values ranging from 20 to 95 kL/hh/y with an average mean of 50 kL/hh/y. Median water consumption values, ranged in mains water reductions from 28 to 52 kL/hh/y, with an average median of 40 kL/hh/y. Considering both measures an average water saving between 40 and 50 kL/hh/y can be expected from internally plumbed rainwater tanks. Water restrictions appear to have a strong influence on estimated reductions in mains water use. In regions where water restrictions were severe, water consumption was less varied between No Tank and IPT homes with a consequent reduction in estimated savings observed. Recommendations for further work include a survey to capture confounding factors that could not be fully controlled in the desktop study and a controlled pairwise experiment to monitor water consumption from raintanks.     

利用雨水收集回用系统实现城市小区雨水资源化

北方城市的缺水状况日益突出,严重限制了城市的发展和经济竞争力提高.发展城市小区雨水收集回用系统,充分利用雨水资源,对缓解城市用水紧张,提高城市防洪能力和保证城市的可持续发展都具有重要的意义.小区雨水收集回用系统包括雨水收集和雨水回用两个方面,由于小区地表与建筑物顶部受人类活动影响的程度不同,所以降落在上面的雨水水质也有很大差别.为了将水质不同的雨水分开利用,降低利用成本,雨水收集回用系统分成屋顶收集回用和地表收集回用两个不同部分.     

Performance Risk Analysis for Fukuoka Water Supply System

In this study, simulation is used to evaluate the performance of the municipal water system in Fukuoka city. In combination with daily simulation model, a kind of risk model incorporating water demand prediction is presented. This model applies five risk indices: reliability, resiliency, vulnerability, drought risk index (DRI) and drought damage index (DDI). They aid in the identification of operation policies for the municipal water system, and the planning and operational policies obtained are aimed at achieving minimum risk for a given scenario of operation. In this paper, the performance risk of the municipal water system is investigated under three alternatives: (1) the existing system operation when available supply from the Chikugo river is decreased; (2) water restrictions for different percentages of reduction are implemented; and (3) available water supply increases when desalination of sea water is implemented. The results obtained show that savings of between 5 and 12% of water consumption from May 1, or increasing of daily desalination of sea water about 30 000 m³ or more, may efficiently decrease the performance risk of the Fukuoka water supply system. Potentials also exist for further increase of reservoir storage by more rational operation. The measure that more attention should be paid to increasing the water supply from stable sources is recommended as well.     

Water Supply System Performance for Different Pipe Materials Part I: Water Quality Analysis

The quality of potable water has been a major issue in the water industry for the last few decades. The deterioration of treated water can be due to physical, chemical or microbiological changes that occur in the water during distribution. In addition, pipe material and decay of a disinfectant agent can affect the quality of the water being distributed. In this study the purpose was to simulate the decay of chlorine in two networks, one made of old cast iron (CI) pipes and another of polyethylene (PE) pipes. In addition the performance of the network considering chlorine concentration, velocity, water age, and an intrusion of a contaminant – in this case organic material – into the network was evaluated. The simulations were performed with EPANET software using as the simulation network an example network from the program. It was found that the CI network requires higher initial chlorine concentrations than the PE network to maintain the required minimum chlorine concentration throughout the whole network. To maintain the chlorine concentrations required by WHO (Cl must be greater than 0.2 mg/l and lesser than 0.5 mg/l) re-chlorination stations were necessary to add into both networks. The performance of both networks before re-chlorination was low due to high initial chlorine concentrations, but after the addition of the re-chlorination stations it was 100% throughout the networks. The performance of the velocities was good in both networks. The performance of the water age was dependent mainly on the tank usage, and the performance of contamination by organic material depended on the coefficient that defines the decay rate of the organic material in the bulk phase.     

Thai Rural Domestic Water Consumption: A Case Study of a Village Community With No Organized Water Supply System

ABSTRACT

Thai rural domestic water consumption of 282 households for 59 villages in Amphoe Nong Sua, Pathum Thani Province, Thailand, is examined in this study. The paper describes the pattern of rural domestic water use and evaluates the factors which affect per capita rural water consumption. Stepwise regression analysis was applied to assess the variables which were postulated to be associated with per capita rural water consumption. The variables that were found to be significantly associated with per capita rural water consumption were household size, average household age, level of education, average household income and number of baths per day.     

Conservation Effects of Irrigation Water Supply Pricing: A Case Study from Oahu,Hawaii

THE CONSERVATION EFFECTS OF IRRIGATION WATER SUPPLY PRICING ARE EXAMINED BY EMPLOYING DATA ON IRRIGATION WATER USE FROM THE HONOLULU BOARD OF WATER SUPPLY (BWS) AND THE WAIMANALO IRRIGATION SYSTEM FOR THE PERIOD OF 1982/83-1991/92. A WATER CONSUMPTION MODEL WAS USED FOR THIS PURPOSE. THE OLS PROCEDURE INDICATED THE EXISTENCE OF AR(1) AUTOCORRELATION IN RESIDUALS. TO MAKE ALLOWANCE FOR THIS, THE ORCUTT-COCHRANE PROCEDURE WAS EMPLOYED TO ESTIMATE THE REGRESSION EQUATIONS. NO EVIDENCE OF WATER PRICING PROMOTING WATER CONSERVATION WAS FOUND IN EITHER CASE. RAINFALL TURNED OUT TO BE THE SINGLE-MOST IMPORTANT VARIABLE IN EXPLAINING THE CHANGES IN AGRICULTURAL USE IN THE STUDY AREAS.     

中国国有企业业绩评价和战略关系研究案例分析

以案例分析的形式对企业业绩评价和战略关系进行了深入研究,揭示了中国国有企业现存业绩评价体系如何促进或阻碍了企业战略的实现,探索了在中国国有企业实施平衡计分卡的可能性、必要性及实施过程中可能遇到的有关问题。     

Water Supply System Performance for Different Pipe Materials Part II: Sensitivity Analysis to Pressure Variation

In water supply systems there are many situations during normal operation that induce the occurrence of pressure transients, where high pressures are followed by low, sometimes even negative pressures. These transients may cause ruptures in pipes creating thus leaks or opportunities for contaminants to enter the water supply system. Thus severe pressures transients should be avoided or adequately controlled in potable drinking systems. The level of service provided by water distribution systems is an important matter in the water industry of today. However, the measure of the performance of a pipe system network is not a straightforward task. In this study the performance of pressures in two networks (a cast iron network and a polyethylene network) with the same typology was compared. The transient state conditions were induced by different typical hydromechanical devices operation characterised by a sudden pumps trip-off, a leakage occurrence and a closure of an automatic control valve. For the hydraulic simulations, advanced models based on numerical computation for steady and transient state conditions were used. A performance evaluation model was developed to analyse each type of situation since the simulation time period and the concerns regarding the system behaviour can be fairly different.     

Performance Measurement and Strategy: A Case Study of SOE in China

The state-owned Enterprises (SOEs thereinafter) are thecorporates owned or controlled completely or partially by gov-ernment through capital link. They have been playing a criticalrolein China economy . However ,the poor performance andtheintrinsic ineffi…     

Residential Water Demand in a Fast-growing Metropolis: The Case of Honolulu,Hawaii

Multi-unit housing residents are important consumers of fresh water in the City and County of Honolulu (CCH). This study examined water use in private multi-unit residences as well as Hawaii Housing Authority (HHA) multi-units in relation to variables such as price of water, number of units, income of residents, etc. using monthly water use data of the top 100 Honolulu Board of Water Supply (BWS) water users. The generalized least squares (GLS) procedure was used to estimate the regressionequations, although the results of ordinary least squares (OLS) estimation are also presented.Based on the results, inducing lower water use by raising the water price appeared somewhat feasible in the case of private multi-unit residences. The same was not, however, true in the case of HHA housing units. A long-term plan to make the water users (who have so far been shielded from bearing the cost directly) pay for water directly (by installing water meters for individual units) has been suggested to promote the prudent use of water.     

城市雨水利用技术体系构建研究

结合城市降雨与径流特点和下垫面特点,从城市降雨径流的产生、地面与管网的汇流、河道的行洪与调节和城乡之间的上下游区域关系与应用条件等多方面综合考虑,构建小区、城市河湖、城乡联调3个层面的城市雨水利用技术体系框架,为城市雨水科学、合理的利用提供参考和借鉴。     

Application of Monte Carlo Simulation Technique to Design Flood Estimation: A Case Study for North Johnstone River in Queensland, Australia

The traditional rainfall-runoff modelling based on the Design Event Approach has some serious limitations as this ignores the probabilistic nature of the key flood producing variables in the modelling except for rainfall depth. A more holistic approach of design flood estimation such as the Joint Probability Approach/Monte Carlo simulation can overcome some of the limitations associated with the Design Event Approach. The Monte Carlo simulation technique is based on the principle that flood producing variables are random variables instead of fixed values. This allows accounting for the inherent variability in the flood producing variables in the rainfall-runoff modelling. This paper applies the Monte Carlo simulation technique and hydrologic model URBS to a large catchment with multiple pluviograph and stream gauging stations. It has been found that it is quite feasible to apply the Monte Carlo simulation technique to large catchments. The Monte Carlo simulation technique has much greater flexibility than the Design Event approach and can provide more realistic design flood estimates with multiple scenarios, which is likely to replace the Design Event Approach. The method developed here can be applied to other catchments in Australia and other countries.     

Multicriterion Analysis for Sustainable Water Resources Planning: A Case Study in Spain

The present article demonstrates the implementation of Multicriterion Decision Making (MCDM) analysis for a case study of Flumen Monegros irrigation area in the Huesca province of Spain. The criteria used to rank alternativesconsist of (1) economic factors including initial cost ofirrigation system, maintenance cost, profitability of crops,extent of European subsidies; (2) environmental factors whichcomprise water volume, water quality after irrigation, efficiency of the use of water, resistance to floods or droughts; (3) Social factors including employment of rurallabour, area non-cultivated. Alternative policies areformulated by mixing factors such as irrigation system, waterpricing, water allocation, crop distribution, fertiliser use,subsidies received. Multicriterion Sorting Technique (MCST)ELECTRE-TRI is employed to reduce the large size payoff matrixto predefined categories for further usage of MCDM techniques.Five MCDM techniques, namely, PROMETHEE-2, EXPROM-2, ELECTRE-3, ELECTRE-4, and Compromise Programming (CP) are employed torank the alternatives. Spearman rank correlation coefficientis employed to assess the correlation coefficient between theranking patterns obtained by the above MCDM techniques.Additive ranking principle is used for group decision makinganalysis. Results indicate that five MCDM techniques choosethe same alternative strategy as the preferred one.     

Simulating the Impact of Pricing Policies on Residential Water Demand: A Southern France Case Study

The case study conducted in this paper looks at residential water pricing from three different points of view. It first describes existing urban water-pricing practices in Southern France, emphasizing that pricing is not yet being used as a tool for providing economic incentives to save water. It then looks at the observed impact of pricing on water consumption, through an econometric analysis of a cross-sectional data set. The analysis suggests that demand, with an estimated price elasticity of −0.2, is not yet very responsive to price variation. A regional water model (300 municipalities) is then developed and used to simulate the potential impact of various water-pricing scenarios on aggregate water demand, aggregate water sales revenue, and consumer surpluses. The results illustrate the trade-offs that have to be made between the search for environmental effectiveness, cost recovery, and equity when implementing complex water-pricing structures such as block rates or seasonal water pricing.     

Temperature Performance of Different Pervious Pavements: Rainwater Harvesting for Energy Recovery Purposes

Pervious pavements offer a solution for rainwater runoff treatment in urban areas, combining storm-water management with water reuse purposes when the sub-bases become rainwater reservoirs. Furthermore, the thermal behaviour research into these systems has demonstrated their contribution to palliating the urban heat island effect in the hottest season and to delaying freezing during the coldest season. Recent investigations related to pervious pavements and their sub-bases have enabled the use of these structures combined with Ground Source Heat Pumps (GSHP) in addition to the other well-known applications. The aim of this field study is to investigate the temperature response observations of the water stored in the sub-bases of different pervious pavements under specific conditions, in order to evaluate the possibility of introducing GSHP technology. The base and sub-base temperatures of different types of pervious pavements were monitored during one year and the results obtained show the differences in pervious pavements temperature compared to air temperature over the period of study; and demonstrate that the sub-base is less affected by the air temperature than the base, due to the insulating capacity of pervious pavements. On the other hand, water samples were taken from the different pervious pavement sub-bases in order to assess the water quality deterioration due to the temperatures reached in the sub-base, focused on investigating the presence of Legionella in this particular aquatic environment.     

Source Choice Perception and Sustainable Rural Water Supply Development: A Case Study of Ban Thadindam,Lopburi, Thailand

Abstract

This study seeks to examine source choice perception and sustainable rural water supply development in Ban Thadindam, a Thai village situated about 220 km north of Bangkok. It makes use of an elementary schematic matrix that was initially developed for the valuation of water sources as perceived by water users in East Africa. In applying the elementary choice scheme, the author interviewed the village Kamnan (district officer) and a few villagers. The results of this study show that a wide range of water supply sources was perceived by the Kamnan. Out of a practical range of six sources, four were perceived and accepted, roof (rain water), river, spring, and pond; and two were perceived but not accepted: well and canal. The reason why well and canal water sources were rejected was because of their hardness and turbidity. Of the four sources accepted, roof (rain water) was rated very favorably as the preferred choice while river, spring, and pond sources were judged equally favorable. Awareness of source choice and the conditions under which choice is made is crucial for the understanding and development of sustainable rural water supply. By adopting a wide combination of sources and integrating them to provide a rich water supply for treatment, and by taking advantage of filtration technology given by the Asian Institute of Technology, Environmental Engineering Division, the villagers, with the help of the Project Managing Committee, transformed the demonstration filtration facility into a sustainable rural water supply system. The latter succeeded not only in providing adequate filtered water for the majority of the households in Ban Thadindam but also in satisfying the water requirements for the whole village for two decades. The success of the rural water supply system has been attributable to many factors, but most important was the awareness the villagers have in the understanding of the interrelations between landscape, range of choice and the interaction between community participation, technology, and environment.     

金沙县农村饮用水安全与地下水开发的分析与探讨

由于金沙县特殊的自然环境和地形地质条件,当地的水资源的开发与利用十分困难。根据调查饮水不安全资料表明,全县饮水不安全人口总数达22.21万人,占全县总人口的37%。在分析金沙县农村饮水安全现状、存在的问题等基础上,以贵州省金沙县长坝乡硐口地下河开发利用示范为例,强调地下水开发利用在解决农村饮水安全工作中地位。     

An Evaluation of Demand for and Supply of Potable Water in an Urban Centre of Abeokuta and Environs, Southwestern Nigeria

The current and future demand for potable water supply to Abeokuta city and environs in southwestern Nigeria were estimated in this study. The estimated water demands, up to the year 2030, were based on population growth and per capita water consumption. The study also investigated whether the present source of public water supply to the city and environs could meet the estimated demand. The consumption standards of 120 and 60 l per capita per day for urban and semi-urban water supplies respectively, recommended in the Nigerian Water Supply and Sanitation Policy, were used for domestic demand estimates. The institutional, industrial, fire service, horticulture and animal husbandry water requirements were based on reasonable percentages of the total domestic demand. The flow of Ogun River, which is the source of raw water for the Abeokuta Water Supply scheme serving Abeokuta city and environs, was assessed and found sufficient to meet the estimated future potable water requirements of the study area. The study indicated that the estimated current annual potable water demand of Abeokuta city and environs (in 2011) is 5.52 × 10⁷ m³ (1.51 × 10⁵ m³/day) and the projected annual potable water demand for the year 2030 is 7.67 × 10⁷ m³ (2.10 × 10⁵ m³/day). At a design capacity of 1.62 × 10⁵ m³/day, the total water supply from the Abeokuta Water Supply Scheme at full capacity will just be about the total required in 2014. By 2015, the scheme will no longer be adequate to meet the total water required, even if it is run at full capacity. It is therefore imperative that the current scheme is expanded within the next 4 years in order to meet the potable water demand of the intended population.     

小流域防洪预警体系的初步研究——以浙江省为例

针对小流域山洪灾害的特点和防洪预警体系的现状,对小流域防洪预警体系进行了研究。运用成熟的水文概念模型、山洪灾害临界雨量值概念和定点降雨数值预测模型,对小流域的山洪灾害进行精细化分析,并结合流域实时和预测信息进行流域山洪灾害预警体系的研究。