STUDYING OF WATERHAMMER PHENOMENON CAUSED BY SUDDEN VARIATION OF WATER DEMAND AT WATER SUPPLY PIPES NETWORK

Being Austria's fourth largest water-supply company, the Grazer Stadtwerke AG., has ensured the successful water-supply of the Styrian capital with 250.000 inhabitants for many years. The average daily water demand of the area amounts to about 50,000 m3. Approximately 30 % of the total demand is covered by the bulk water supply from the Zentral Wasser Versorgung Hochschwab Süd. The waterworks Friesach and Andritz, which cover the additional 70 % of the water demand, operate by means of artificial groundwater recharge plants where horizontal filter wells serve as drawing shafts. The groundwater recharge systems serve to increase the productivity of the aquifer and to reduce the share of the infiltration from the Mur River. Protection areas have been identified to ensure that the water quality of the aquifer stay at optimal levels. The protection areas are divided into zones indicating various restrictions for usage and planning. Two respective streams serve as the source for the water recharge plants. Different infiltration systems are utilised. Each of the various artificial groundwater recharge systems displays specific advantages and disadvantages in terms of operation as well as maintenance. In order to secure a sustainable drinking water supply the recharge capacity will be increased. Within an experimental setting different mixtures of top soils are investigated with respect to infiltration and retention rates and compared to the characteristics of the existing basins. It can be shown that the current operating sand basin with more than 90% grains in the range between 0.063 and 6.3 mm represents the best combination of infiltration and retention rates. In future experiments the performance of alternative grain size distributions as well as planting the top soil will be tested. Additionally, in order to optimize the additional groundwater recharge structures the composition of the subsurface water regarding its origin is statistically analyzed.

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Assessment of the need and potential for groundwater artificial recharge based on the water supply, water demand, and aquifer properties in a water shortage region of South Korea

Environmental Earth Sciences ◽

10.1007/s12665-021-09445-5 ◽

2021 ◽

Vol 80 (3) ◽

Author(s):

Gyoo-Bum Kim ◽

Chan-Ik Hwang ◽

Myoung-Rak Choi

Keyword(s):

South Korea ◽

Water Supply ◽

Water Demand ◽

Artificial Recharge ◽

Water Shortage ◽

Aquifer Properties ◽

Supply Water

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Assessing Future Water Demand and Associated Energy Input with Plausible Scenarios for Water Service Providers (WSPs) in Sub-Saharan Africa

Energies ◽

10.3390/en14082169 ◽

2021 ◽

Vol 14 (8) ◽

pp. 2169

Author(s):

Pauline Macharia ◽

Nzula Kitaka ◽

Paul Yillia ◽

Norbert Kreuzinger

Keyword(s):

Water Supply ◽

Water Demand ◽

Energy Input ◽

Service Providers ◽

Sub Saharan Africa ◽

Water Losses ◽

Water Service ◽

Current State ◽

Per Capita ◽

Sub Saharan

This study examined the current state of water demand and associated energy input for water supply against a projected increase in water demand in sub-Saharan Africa. Three plausible scenarios, namely, Current State Extends (CSE), Current State Improves (CSI) and Current State Deteriorates (CSD) were developed and applied using nine quantifiable indicators for water demand projections and the associated impact on energy input for water supply for five Water Service Providers (WSPs) in Kenya to demonstrate the feasibility of the approach based on real data in sub-Saharan Africa. Currently, the daily per capita water-use in the service area of four of the five WSPs was below minimum daily requirement of 50 L/p/d. Further, non-revenue water losses were up to three times higher than the regulated benchmark (range 26–63%). Calculations showed a leakage reduction potential of up to 70% and energy savings of up to 12 MWh/a. The projected water demand is expected to increase by at least twelve times the current demand to achieve universal coverage and an average daily per capita consumption of 120 L/p/d for the urban population by 2030. Consequently, the energy input could increase almost twelve-folds with the CSI scenario or up to fifty-folds with the CSE scenario for WSPs where desalination or additional groundwater abstraction is proposed. The approach used can be applied for other WSPs which are experiencing a similar evolution of their water supply and demand drivers in sub-Saharan Africa. WSPs in the sub-region should explore aggressive strategies to jointly address persistent water losses and associated energy input. This would reduce the current water supply-demand gap and minimize the energy input that will be associated with exploring additional water sources that are typically energy intensive.

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Mathematical Models for Predicting and Managing Water Resources — The Case of China in 2025

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.448-453.995 ◽

2013 ◽

Vol 448-453 ◽

pp. 995-1001

Author(s):

Ning Na Wang ◽

Qin Lin Zhou

Keyword(s):

Water Supply ◽

Water Demand ◽

Optimal Allocation ◽

Supply And Demand ◽

Decision Makers ◽

Grey System ◽

Allocation Model ◽

Water Supply Management ◽

Generate Solution ◽

Major Factors

An effective management of water supply is critically significant to a countrys water utilities, and accurate prediction of water supply and demand is of key importance for water supply management. The objectives of this paper are to use Grey System Model (GSM) and Linear Regression Model to forecast the water demand and water supply respectively in China 2025, and then propose a new Optimal Allocation Model (OAM) to generate solution so that analysts and decision makers can gain insight and understanding. The two predictive models take into account four major factors including domestic development, agriculture, industries and eco-environment, calculating a deficit between water demand and water supply in China 2025. Then the OAM, which considers desalinization, irrigation saving and urban recycling, provides a feasible solution to fill the gap and an effectual management of water supply.

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Determination of the optimal capacity of a reservoir considering the effects of flood control volume change on its performance (case study: Darband dam, Iran)

Water Practice & Technology ◽

10.2166/wpt.2014.057 ◽

2014 ◽

Vol 9 (4) ◽

pp. 509-518

Author(s):

R. Shahsavan ◽

M. Shourian

Keyword(s):

Water Resources ◽

Water Supply ◽

Volume Change ◽

Water Demand ◽

Flood Control ◽

Control Volume ◽

Study Phase ◽

Hydroelectric Power ◽

Software Environment ◽

Optimal Capacity

Water storage using dams is a perfect solution for agricultural, industrial, drinking water supply, flood control, hydroelectric power generation, and other purposes. Integrated management of water resources involves the development, management, protection, regulation and beneficial use of surface- and ground- water resources. The reliability of water supply reservoirs depends on several factors, e.g. the physical characteristics of the reservoir, the time series of river discharge, climatic conditions, the amount of demand, and the method of operation. If a portion of a dam's volume is kept empty for flood control, the confidence values of taking the bottom water demand will be reduced. In this paper, a yield-storage model developed in a MATLAB software environment is used to determine the optimal capacity of Darband dam in northeast Iran (the study phase). The reservoir's performance with respect to demand downstream, e.g. from industry and agriculture, and for potable use, was studied, and the results compared for scenarios in flood control volume change conditions. The results show that, for a capacity of 80 Mm3, the reliability values for meeting agricultural, environmental, and potable water demand are estimated at 0.922, 0.927, and 0.942, respectively. If the reservoir's capacity is changed from 80 to 350 Mm3, the reliability values increase by only about 7%.

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Beijing water resources and the south to north water diversion project

Canadian Journal of Civil Engineering ◽

10.1139/l04-113 ◽

2005 ◽

Vol 32 (1) ◽

pp. 159-163 ◽

Cited By ~ 22

Author(s):

Duan Wei

Keyword(s):

Water Resources ◽

Water Supply ◽

Water Demand ◽

Socioeconomic Development ◽

Water Environment ◽

Water Saving ◽

Water Diversion ◽

The South ◽

Water Diversion Project ◽

North Water

Beijing is located in a semiarid region, and water shortage is a common problem in the city. Along with the rapid increase in water demand, due to fast socioeconomic development and an increase in population, a shortage of water resources and a deterioration of the water environment have become obstacles to sustainable socioeconomic development in Beijing. In the long run, sustainable water resources management, water conservation, and completion of the south to north water diversion project will solve the problem. This paper introduces the water resources situation in Beijing; analyzes future water demand; and discusses the actions of water saving, nontraditional water resources exploitation, wetland construction, and water environment protection. The paper also explains the importance of the south to north water diversion project and the general layout of the water supply strategy, water distribution system, and methods to efficiently use the diverted water in Beijing.Key words: water resources, water supply, water saving, water recycling, water diversion.

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Hydraulic Performance Analysis and Modeling of Water Supply Distribution System of Addis Ababa Science and Technology University, Ethiopia

10.20944/preprints202002.0149.v1 ◽

2020 ◽

Author(s):

Chalchisa Milkecha ◽

Habtamu Itefa

Keyword(s):

Water Supply ◽

Water Demand ◽

Distribution System ◽

Distribution Systems ◽

Water Distribution ◽

Addis Ababa ◽

Science And Technology ◽

Hydraulic Performance ◽

Alternative Methods ◽

The University

This study was conducted generally by aiming assessment of the hydraulic performance of water distribution systems of Addis Ababa Science and Technology University (AASTU). In line with the main objective, this study addressed, (1) pinpointing problems of existing water supply versus demand deficit (2) evaluating the hydraulic performance of water distribution system using water GEMS and (3) recommended alternative methods for improving water demand scenarios. The University’s water supply distribution network layout was a looped system and the flow of water derived by both gravity and pressurized system. The gravity flow served for the academic and administrative staffs whereas the pressurized system of the network fed the students dormitories, cafeteria’s etc. The study revealed the existence of unmet minimum pressure requirement around the student dormitories which accounts 25.64% below the country’s building code standard during the peak hour consumption. The result of the water demand projection showed an increment of 2.5 liter per capita demand (LPCD) in every five years. Hence, first, the university’s water demand was projected and then hydraulic parameters such as; pressure, head loss and velocity were modeled for both the existing and the improved water supply distribution. The finding of the study was recommended to the university’s water supply project and institutional development offices for its future modification and rehabilitation works.

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Sustainability characteristics of drinking water supply

10.5194/dwes-2020-8 ◽

2020 ◽

Author(s):

Jolijn van Engelenburg ◽

Erik van Slobbe ◽

Adriaan J. Teuling ◽

Remko Uijlenhoet ◽

Petra Hellegers

Keyword(s):

Drinking Water ◽

Water Supply ◽

Water Demand ◽

Supply System ◽

Water Supply System ◽

Drinking Water Supply ◽

Extreme Weather Events ◽

Water Supply Systems ◽

Global Issues ◽

Drinking Water Supply System

Abstract. Developments such as climate change and growing demand for drinking water threaten the sustainability of drinking water supply worldwide. To deal with this threat, adaptation of drinking water supply systems is imperative, not only on a global and national scale, but particularly on a local scale. This investigation sought to establish characteristics that describe the sustainability of local drinking water supply. We use an integrated systems approach, describing the local drinking water supply system in terms of hydrological, technical and socio-economic characteristics that determine the sustainability of a local drinking water supply system. Three cases on drinking water supply in the Netherlands are analysed. One case relates to a short-term development, that is the 2018 summer drought, and two concern long-term phenomena, that is, changes in water quality and growth in drinking water demand. The approach taken recognises that next to extreme weather events, socio-economic developments will be among the main drivers of changes in drinking water supply. Effects of pressures associated with, for example, population growth, industrial developments and land use changes, could result in limited water resource availability, deteriorated groundwater quality and growing water demand. To gain a perspective on the case study findings broader than the Dutch context, the sustainability issues identified were paired with global issues concerning sustainable drinking water supply. This resulted in a proposed set of generally applicable sustainability characteristics, each divided into five criteria describing the hydrological, technical and socio-economic sustainability of a local drinking water supply system. Elaboration of these sustainability characteristics and criteria into a sustainability assessment can provide information on the challenges and trade-offs inherent in the sustainable development and management of a local drinking water supply system.

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Analysis of the water meter management of the urban-rural water supply system

E3S Web of Conferences ◽

10.1051/e3sconf/20184400051 ◽

2018 ◽

Vol 44 ◽

pp. 00051 ◽

Cited By ~ 1

Author(s):

Joanna Gwozdziej-Mazur ◽

Kamil Świętochowski

Keyword(s):

Water Supply ◽

Water Demand ◽

Supply System ◽

Water Supply System ◽

Water Losses ◽

Rural Water Supply ◽

Rural Water ◽

Urban Rural ◽

Water Supply Company ◽

Water Meter

Water losses in the water supply network pose a continuous challenge for water companies. Already during designing new networks, the designer assumes that the amount of water demand must be increased by a certain percentage (usually by 10% of the total average daily water demand for municipal and industrial purposes) due to the possible occurrence of water losses. Water loss is meant the difference between the amount of water injected into the network and the amount of water used and invoiced, i.e. that brings income for the water supply company. Proper water metering management helps to limit water losses. This paper presents analysis of the water meter management of urban-rural water supply system.

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