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Deciding to RechargeEden, Susanna, Davis, Donald R. 12 1900 (has links)
Public water policy decision making tends to be too complex and dynamic to be
described fully by traditional, rational models. Information intended to improve
decisions often is rendered ineffective by a failure to understand the process. An
alternative, holistic description of how such decisions actually are made is presented here
and illustrated with a case study. The role of information in the process is highlighted.
Development of a Regional Recharge Plan for Tucson, Arizona is analyzed as the case
study.
The description of how decisions are made is based on an image of public water
policy decision making as 1) a structured, nested network of individuals and groups with
connections to their environment through their senses, mediated by their knowledge; and
2) a nonlinear process in which decisions feed back to affect the preferences and
intentions of the people involved, the structure of their interactions, and the environment
in which they operate. The analytical components of this image are 1) the decision
makers, 2) the relevant features of their environment, 3) the structure of their interactions,
and 4) the products or outputs of their deliberations. Policy decisions analyzed by these
components, in contrast to the traditional analysis, disclose a new set of relationships and
suggest a new view of the uses of information.
In context of information use, perhaps the most important output of the decision
process is a shared interpretation of the policy issue. This interpretation sets the
boundaries of the issue and the nature of issue-relevant information. Participants are
unlikely to attend to information incompatible with the shared interpretation. Information
is effective when used to shape the issue interpretation, fill specific gaps identified as
issue-relevant during the process, rationalize choices, and reshape the issue interpretation
as the issue environment evolves.
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WATERBUD: A SPREADSHEET-BASED MODEL OF THE WATER BUDGET AND WATER MANAGEMENT SYSTEMS OF THE UPPER SAN PEDRO RIVER BASIN, ARIZONABraun, David P., Maddock, Thomas III, Lord, William B. 07 1900 (has links)
This report describes the development and application of a spreadsheet -based
model of the water budget and water management systems of the Upper San Pedro River
Basin in southeastern Arizona. The model has been given the name, WATERBUD.
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Kvalitetsgranskning av flödesdata från vattenledningsnätet / Quality control of flow meter data from water supply networksEliasson, Victor January 2016 (has links)
In an attempt to revise the guidelines which are the basis of today’s design of water and sewage systems, Tyréns carries out a project for Swedish Water & Wastewater Association (SWWA). This SWWA project aims to, based on flow meter data, map out the behavior pattern regarding water consumption for certain types of consumers, such as industrial or individual users. The overall goal is to get a better support for the dimensioning process. A prerequisite for SWWA study is that the data to be analyzed are of good quality. Therefore this thesis will be included as a sub-study for the SWWA project with the goal to find and test methods for quality control of the flow meter data. This thesis showed some methods to statistically validate the data. A method is for instance presented that is used to detect changes in the statistical distribution for the sets of flow meter data. The changes that were studied were either changes in mean or variance. The latter turned out to be able to detect sequences, mostly during the summer, when the daily variations in water demand is different than during the rest of the year. Furthermore, some outliers could be identified using regression analysis. Some measurement errors, such as repeated flow values, could also be detected using run length encoding. In identifying anomalies and outliers, some types of those were possible to explain as false flow observation or non-representative for the data series as a whole for further analysis in the SWWA project. Other suspected observations were not possible to declare as true erroneous and have therefore been flagged for further investigation with support by an expert in the field. / I ett försök att revidera de riktlinjer som ligger till grund för dagens dimensionering av vatten- och avloppsledningsnät, genomför Tyréns ett projekt för Svenskt Vatten Utveckling (SVU). Detta SVU-projekt syftar till att utifrån flödesdata från vattenledningsnätet kartlägga beteendemönster hos olika förbrukartypers vattenförbrukning, såsom storförbrukare och enskilda brukare, för att på så vis kunna erhålla bättre och mer aktuella underlag för dimensioneringen. En förutsättning för SVU-studien är att det mätdata som ska analyseras håller god kvalitet. Därför kommer detta examensarbete att ingå som en understudie till SVU-projektet med syftet att finna en metod för att kvalitetsgranska flödesdata. Detta examensarbete visade metoder för att statistiskt granska flödesdatat med avseende på outliers och anomalier. Bland annat presenterades en metod för att finna förändringar i mätseriernas statistiska fördelning. De förändringar som studerades var antingen förändring av medelvärde eller en förändring av variansen. Den senare visade sig kunna detektera sekvenser, framförallt under sommaren, där dygnsvariationen i vattenförbrukningen ofta var annorlunda mot resten av året. Vidare kunde outliers detekteras med hjälp av regressionsanalyser på mätserierna. Olika mätfel, exempelvis mätvärden som upprepas, kunde även identifieras med hjälp av skurlängdskodning. Vid identifiering av anomalier eller outliers har vissa typer kunnat detekteras och förklarats som felaktiga värden eller icke representativa för mätserien för vidare analyser. Andra identifierade suspekta mätvärden har inte kunnat förklaras eller det har inte kunnat säkerställas att de är felaktiga. Dessa har markerats och bör studeras av en expert inom ämnesområdet.
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"This is people's water" : water services struggles and the new social movements in Mpumalanga, Durban, 1998-2005Siwisa, Buntu Sesibonga January 2006 (has links)
This thesis forms part of the emerging studies on the backlogs in municipal services delivery and the attendant emergence of the new social movements in post-apartheid South Africa. It examines four areas. These are: the backlogs in water services delivery; the consequent politicisation of the water services struggles; the breakdown of social citizenship; and the nature, forms and the repertoire of the collective action of the new social movements. The thesis is based on fieldwork research I undertook in 2002 on the water services struggles in Mpumalanga, an African township located outside the small town of Hammarsdale in Durban. The fieldwork research results reveal the demographic characteristics of Mpumalanga and, more crucially, the extent of the water services crisis. The results evaluate the nature and the gravity of the water services delivery backlogs. More importantly, they gauge the depth of their involvement in the water services struggles in Mpumalanga and the extent of their success. These are weighed against the reports of the new social movements' involvement in the township by the leftist-cum-intellectual activists in Durban and by the leftist and mainstream media reports. They also revealed a detailed picture of the state of collective action in Durban, unearthing the nature and functioning of the Concerned Citizens' Forum (CCF), an umbrella-body of Durban-based social movements. The study questions the hallowed standing of the CCF, by claiming, through detailed study and fieldwork observation, that the CCF is given to 'crowd renting', lack of transparency, disorderly decision-making, racial and leadership crises. The thesis also contextualises the collective action programmes of the CCF by situating them in Mpumalanga's neighbourhood politics. By doing so, the reader encounters ruling party local councillors, opposition party local councillors, CCF leaders and intellectual-cum-activists, youth activists and local council officials and bureaucrats. The collusion and conflicts between these parties and stakeholders bring into the equation political opportunism, careerism, and the ruthless pursuit of financial gains. All these parties and variables reveal a complex and ever-shifting picture of collective action and the contentious politics of the new social movements in Mpumalanga and Durban, amidst the looming crisis of the breakdown of social citizenship, cost recovery and the water services struggles.
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Funding of Southern African water projects by international donors : a study of ORASECOMMthembu, Hazel Duduzile. January 2015 (has links)
M. Tech. Business Administration / The scarcity of sustainable adequate water resources is one of the world’s leading problems and is currently affecting more than 1.1 billion people in Africa. This research study contributes towards the existing body of knowledge on the criteria applied by the International Co-operating Partners (ICPs) or Donors in financing water projects in Southern Africa. The primary purpose of the study was to explore the rationale behind why ICPs are motivated to fund water projects within Orange-Senqu River Commission (ORASECOM) and also to describe the expectations by ICPs from funding developing countries water infrastructure projects.
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Water sustainability : measurement, management, engagement, and disclosure of selected water-intensive companies on the Johannesburg Stock ExchangeAskham, Theresa 01 1900 (has links)
Many parts of the world, but South Africa specifically, are facing a water crisis, not only because of the scarcity of water, but also the quality of the water that is available. Companies are the primary users of water and can therefore have the most significant impact on saving water. It is thus imperative to determine how companies are measuring, managing, engaging with their stakeholders and disclosing water-related risks in their businesses. This study was conducted on the premise that South African companies have not as yet grasped the seriousness of the water crisis. Thirty JSE-listed companies classified as being water intensive were selected for the study. Their sustainability/integrated/annual reports for 2011 and 2013 were downloaded from the internet and analysed to determine if and how they were mitigating their water-related risks. The Ceres Aqua Gauge™ was used as the framework for this study. It was established during the analysis of the selected companies’ reports that, with the exception of food producers and food retailers, the companies had grasped the seriousness of the water crisis. One area of particular concern that was evident in all the companies was the lack of attention directed towards supply chain water management. Companies need to address water risks in their supply chain, and to also turn the water crisis from a threat into an opportunity. Investors need to engage with and put pressure on companies to improve their water management practices. / Business Management / M. Ph. Accounting Sciences (Management Accounting)
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Hydrological modelling under limited data availability : a case study of Umdloti River, South AfricaMashiyane, Thulasizwe Innocent January 2016 (has links)
Submitted in fulfillment of the requirements for the degree of Master of Engineering, Department of Civil Engineering and Surveying, Durban University of Technology, Durban, South Africa, 2016. / Due to the water scarcity in South Africa, new strategies in management planning are needed in order to sustain water resources. The increase of population and economic growth in South Africa has a negative effect on the water resources. Therefore, it should be well managed. The main concerns of the sustainability of water resources are hydropower, irrigation for agriculture, domestic and industries. Hence, the use of integrated water resources management in a single system which is built up by a river basin will help in water resources. This study was focused on water management issues: some of the principal causes of water shortages in UMdloti River are discussed. The current situation of water supply and demand at present is discussed. It also addressed some essential elements of reasonable, cooperative and sustainable water resources management solutions. Many developing countries are characterized as there is limited data availability, water scarcity and decrease of water levels in the dams. The eThekwini municipality is also having similar problems. Water resources have been modelled under this limited data using the hydrological modelling techniques by assessing the streamflow and observed data. The aim of the study was to address the issue of water management how water supply sources can be sustained to be manageable to meet the population growth demand considering the capacity of Hazelmere Dam demand downstream of the dam. Hydrological models, simulation, and decision making support systems were used to achieve all the research objectives. Hazelmere Dam has been modelled so that it can be used efficiently for the benefit of all users downstream of the dam for their economic and ecological benefits. Monthly reservoir inflow data for Hazelmere Dam was obtained from the Department of Water Affairs, South Africa. The nature of data is streamflow volume in mega liter (Ml) recorded for every month of the year. This was converted to mega cubic meter (Mm3) for use in the analysis herein. A period spanning 19 years of data (1994 – 2013) was used for the analysis. Six parametric probability distribution models were developed for estimating the monthly streamflow at Hazelmere Dam. These probability distribution functions include; Normal, Log-Normal (LN), Pearson III, Log-Pearson type III (LP3), Gumbel extreme value type1 (EVI) and Log-Gumbel (LG). It was observed that UMdloti River is smaller when compared with other rivers within the KwaZulu-Natal Province which could make it difficult to implement integrated water resources management. The hydro-meteorological data collected also has some limitations. The meteorological stations are far away to one another and this would make it difficult to attach their readings with the corresponding water basin. The comparison between the observed and simulated streamflow indicated that there was a good agreement between the observed and simulated discharge. Even though, the performance of the model was satisfactory, yet, it should not be generalized equally for all purposes. The erosion on the study area must be addressed by the stakeholders. It must be minimized in order to sustain the water resources of the UMdloti River. Erosion has a bad impact on the environment because it causes environmental degradation as well. Further investigations are recommended that account for the geological characteristics and the source of the base flow to make sure the rate of groundwater is sufficient for any future developments.
Harnessing more energy from existing water sources within the frontier of the country is important in capacitating the South African Government’s commitment to reduction of the country’s greenhouse gas emissions and transition to a low-carbon economy while meeting a national target of 3,725 megawatts by 2030. This study also aimed to determine the amount of energy that can be generated from Hazelmere Dam on the uMdloti River, South Africa. Behavioral analyses of the Hazelmere reservoir were performed using plausible scenarios. Feasible alternative reservoir operation models were formulated and investigated to determine the best operating policy and power system configuration. This study determines the amounts of monthly and total annual energy that can be generated from Hazelmere reservoir based on turbines efficiencies of 75%, 85% and 90%. Optimization models were formulated to maximize hydropower generation within the constraints of existing abstractions, hydrological and system constraints. Differential evolution (DE) optimization method was adopted to resolve the optimization models. The methodology was applied for an operating season.
The optimization models were formulated to maximize hydropower generation while keeping within the limits of existing irrigation demands. Differential evolution algorithm was employed to search feasible solution space for the best policy. Reservoir behavioural analysis was conducted to inspect the feasibility of generating hydropower from the Hazelmere reservoir under normal flow conditions. Optimization models were formulated to maximize hydropower generation from the dam. DE was employed to resolve the formulated models within the confines of the system constraints. It was found that 527.51 MWH of annual energy may be generated from the dam without system failure. Storage was maintained above critical levels while the reservoir supplied the full demands on the dam throughout the operating period indicating that the system yield is sufficient and there is no immediate need to augment the system. / M
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Aspects of the economics of water management in urban settings in South Africa, with a focus on Cape TownJansen, Ada Isobel 03 1900 (has links)
Thesis (PhD)--Stellenbosch University, 2012. / ENGLISH ABSTRACT: Concerns about the sufficiency of freshwater supplies and the impact of water shortages
have placed sustainable water management on the global agenda. This is particularly
relevant in South Africa, a country with precipitation rates well below the global average
and water resources that have become highly polluted. The scarcity of water for
consumption use and of unpolluted water bodies as recreational and environmental good
highlights the need for an economic analysis of these issues. This dissertation investigates
some economic aspects of water management in the South African context in two
distinctive parts. Part One (Chapters 2 to 5) aims to provide an understanding of urban
water demand and analyses water pricing as demand management tool. Part Two
(Chapters 6 and 7) analyses the values people attach to water resources for recreational
and environmental purposes. Quantitative methodological approaches are predominantly
used to inform an economic perspective on water demand management.
The extent of water scarcity is discussed in Chapter Two. South Africa is approaching
physical water scarcity, but many poor households do not yet have access to water and
basic sanitation facilities, i.e. there is also economic water scarcity. Given this background,
Chapter Three focuses on water demand management as part of an integrated water
management approach. The role of water prices is discussed, in particular the Increasing
Block Tariff (IBT) structure which is predominantly used in South Africa.
Chapter Four estimates the price elasticity of demand for water using household water
consumption records obtained from the City of Cape Town (CCT). A distinctive feature of
this case study is a survey undertaken to collect household information on demographic
and water-use characteristics, as water databases are severely lacking in South Africa.
The results show water demand to be mostly price inelastic, which concurs with findings
from international empirical literature. Furthermore, higher-income households are found to
be more sensitive to price changes, thus some reduction in water consumption can be
achieved by increasing marginal prices at the upper end of the IBT structure.
Chapter Five analyses the IBT structure as a redistributive tool. Particular attention is
given to the Free Basic Water policy of South Africa, which allows each household to
receive six kilolitres of water free per month. Empirical modelling indicates that the IBT
structure in its current form holds limited benefits for the poor, given the state of service delivery in South Africa: the lack of access to the water network prevents the poorest
households from being the recipients of the cross-subsidisation occurring in an IBT
structure.
Part Two studies urban water resources as recreational and environmental goods. The
literature review of environmental valuation techniques in Chapter Six places particular
emphasis on the Contingent Valuation Method. This method is applied in Chapter Seven,
where the value of improving the environmental quality of a freshwater urban lake is
analysed in a middle- to low-income urban area. Another survey was undertaken
specifically for this purpose of gauging the willingness to pay for improved recreational
facilities and water quality of Zeekoevlei. The results show that low-income households do
attach value to urban environmental goods, a result which adds to our knowledge of
willingness to pay for environmental goods in developing countries. / AFRIKAANSE OPSOMMING: Besorgdheid oor die toereikenheid van varswaterbronne en die impak van watertekorte het
volhoubare waterbestuur op die wêreldagenda geplaas. Dit is veral relevant vir Suid-
Afrika, 'n land met neerslagkoerse ver onder die wêreld gemiddelde en waterbronne wat
hoogs besoedeld geword het. Die skaarsheid van water vir verbruik en van onbesoedelde
waterbronne as ontspannings- en omgewingsproduk, beklemtoon die noodsaaklikheid vir
'n ekonomiese analise van hierdie kwessies. Hierdie proefskrif ondersoek sekere
ekonomiese aspekte van waterbestuur in die Suid-Afrikaanse konteks, in twee dele. Deel
Een (Hoofstukke Twee tot Vyf) beoog om insig te verskaf oor die stedelike vraag na water
en analiseer die prys van water as 'n vraagbestuursmaatstaf. Deel Twee (Hoofstukke Ses
en Sewe) ontleed die waarde wat mense heg aan waterbronne vir ontspannings- en
omgewingsdoeleindes. Kwantitatiewe metodologiese benaderinge word hoofsaaklik
gebruik om 'n ekonomiese perspektief op watervraag bestuur toe te lig.
Die omvang van waterskaarsheid in Suid-Afrika word in Hoofstuk Twee bespreek. Hierdie
hoofstuk dui aan dat Suid-Afrika besig is om fisiese waterskaarste te bereik, maar die land
het ook baie arm huishoudings wat nog nie toegang tot water en basiese
sanitasiefasiliteite het nie, dw.s. wat daar is ook ekonomiese waterskaarsheid. Gegewe
hierdie agtergrond, fokus Hoofstuk Drie op watervraagbestuur, as deel van 'n
geïntegreerde waterbestuursbenadering. Die rol van waterpryse word bespreek, veral die
Stygende-Blok-Tarief (SBT) struktuur wat grotendeels in Suid-Afrika gebruik word.
Hoofstuk Vier bepaal die pryselastisiteit van vraag vir water met behulp van huishoudelike
waterverbruiksdata, verkry vanaf die Stad Kaapstad. 'n Kenmerkende eienskap van hierdie
gevallestudie is die ingesamelde huishoudelike inligting oor demografiese en
waterverbruik-eienskappe, aangesien daar ‘n groot tekort aan water-databasisse in Suid-
Afrika is. Die uitslae toon dat watervraag meestal prysonelasties is, wat ooreenstem met
bevindinge van ander empiriese literatuur. Verder word gevind dat hoё-inkomste
huishoudings meer sensitief is vir prysveranderinge. Dus sal 'n afname in waterverbruik
bewerkstellig kan word deur marginale pryse aan die hoёr kant van die SBT struktuur te
verhoog.
Hoofstuk Vyf ondersoek die SBT struktuur as 'n effektiewe herverdelingsmaatstaf.
Spesifieke aandag word aan die Gratis Basiese Water-beleid van Suid-Afrika geskenk, wat voorsiening maak dat elke huishouding ses kiloliter water per maand verniet ontvang. Die
bevindinge van empiriese modellering is dat die SBT struktuur, soos dit tans in Suid-Afrika
toegepas word, beperkte voordele vir die armes inhou, gegewe die huidige stand van
watervoorsiening in Suid-Afrika. As gevolg van die agterstand met betrekking tot toegang
tot water, ontvang die heel armes nie die voordele van kruissubsidiёring wat plaasvind
onder 'n SBT struktuur nie.
Deel Twee bestudeer stedelike waterbronne as ontspannings- en omgewingsprodukte.
Hoofstuk Ses verskaf 'n literatuur oorsig oor omgewingswaardasie tegnieke, met 'n
spesieke fokus op die Kontingente Waardasie-metode. Hierdie metode word in Hoofstuk
Sewe toegepas, waar die waarde van verbeteringe in die omgewingskwaliteit van 'n
varswatermeer in 'n middel- tot lae-komste stedelike gebied ondersoek word. Nog 'n
opname is gedoen met die doel om die bereidwilligheid om te betaal vir verbeterde
ontspanningsfasiliteite en die waterkwaliteit van Zeekoevlei te meet. Die bevindinge toon
dat lae-inkomste huishoudings wel waarde heg aan stedelike omgewingsprodukte.
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An evaluation of the minimum requirements for the design of rural water supply projectsChirwa, M. P. W. 12 1900 (has links)
Thesis (MScEng (Civil engineering))--University of Stellenbosch, 2005. / In this study, the minimum standards required for the design of rural piped water supply
projects as set by the Department of Water Affairs and Forestry (DWAF) are evaluated
with respect to capital pipe cost using the Nooightgedacht rural water supply scheme
selected as a case study.
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Probabilistic analysis of monthly peak factors in a regional water distribution systemKriegler, Benjamin Jacobus 12 1900 (has links)
Thesis (MScEng)--Stellenbosch University, 2013. / ENGLISH ABSTRACT: The design of a water supply system relies on the knowledge of the water demands of its specific end-users.
It is also important to understand the end-users’ temporal variation in water demand. Failure of the system to
provide the required volume of water at the required flow-rate is deemed a system failure. The system
therefore needs to be designed with sufficient capacity to ensure that it is able to supply the required volume
of water during the highest demand periods. In practice, bulk water supply systems do not have to cater for
the high frequency, short duration high peak demand scenarios of the end-user, such as the peak hour or peak
day events, as the impact of events is reduced by the provision of water storage capacity at the off-take from
the bulk supply system. However, for peak demand scenarios with durations longer than an hour or a day,
depending on the situation, the provision of sufficient storage capacity to reduce the impact on the bulk water
system, becomes impractical and could lead to potential water quality issues during low demand periods. It
is, therefore, a requirement that bulk water systems be designed to be able to meet the peak weekly or peak
month end-user demands. These peak demand scenarios usually occur only during a certain portion of the
year, generally concentrated in a two to three month period during the drier months. Existing design
guidelines usually follow a deterministic design approach, whereby a suitable DPF is applied to the average
annual daily system demand in order to determine the expected peak demand on the system. This DPF does
not account for the potential variability in end-user demand profiles, or the impact that end-storage has on
the required peak design factor of the bulk system.
This study investigated the temporal variations of end-user demand on two bulk water supply systems. These
systems are located in the winter rainfall region of the Western Cape province of South Africa. The data
analysed was the monthly measured consumption figures of different end-users supplied from the two
systems. The data-sets extended over 14 years of data. Actual monthly peak factors were extracted from this
data and used in deterministic and probabilistic methods to determine the expected monthly peak factor for
both the end-user and the system design. The probabilistic method made use of a Monte Carlo analysis,
whereby the actual recorded monthly peak factor for each end-user per bulk system was used as an input into
discrete probability functions. The Monte Carlo analysis executed 1 500 000 iterations in order to produce
probability distributions of the monthly peak factors for each system. The deterministic and probabilistic
results were compared to the actual monthly peak factors as calculated from the existing water use data, as
well as against current DPFs as published in guidelines used in the industry. The study demonstrated that the
deterministic method would overstate the expected peak system demand and result in an oversized system.
The probabilistic method yielded good results and compared well with the actual monthly peak factors. It is
thus deemed an appropriate tool to use to determine the required DPF of a bulk water system for a chosen
reliability of supply. The study also indicated the DPFs proposed by current guidelines to be too low. The
study identified a potential relationship between the average demand of an end-user and the expected
maximum monthly peak factor, whereas in current guidelines peak factors are not indicated as being
influenced by the end-user average demand. / AFRIKAANSE OPSOMMING: Die ontwerp van ‘n watervoorsiening stelsel berus op die kennis van die water aanvraag van sy spesifieke
eindverbruikers. Dit is ook belangrik om ‘n begrip te hê van die tydelike variasie van die eindverbruiker se
water-aanvraag. Indien die voorsieningstelsel nie in staat is om die benodigde volume water teen die
verlangde vloeitempo te kan lewer nie, word dit beskou as ‘n faling. Die stelsel word dus ontwerp met
voldoende kapasiteit wat dit sal in staat stel om die benodigde volume gedurende die hoogste aanvraag
periodes te kan voorsien. In die praktyk hoef grootmaat water-voorsiening stelsels nie te voldoen aan spits
watergebeurtenisse met hoë frekwensie en kort duurtes, soos piek-dag of piek-uur aanvraag nie, aangesien
hierdie gebeurtenisse se impak op die grootmaat stelsel verminder word deur die voorsiening van wateropgaring
fasiliteite by die aftap-punte vanaf die grootmaatstelsels. Nieteenstaande, vir piek-aanvraag
gebeurtenisse met langer duurtes as ‘n uur of dag, raak die voorsiening van voldoende wateropgaring
kapasiteit by die aftap-punt onprakties en kan dit selfs lei tot waterkwaliteits probleme. Dit is dus ‘n vereiste
dat grootmaat watervoorsienings stelsels ontwerp moet word om die piek-week of piek-maand eindverbruiker
aanvrae te kan voorsien. Hierdie piek-aanvraag gebeurtenisse vind algemeen in gekonsentreerde
twee- of drie maand periodes tydens die droeër maande plaas. Bestaande ontwerpsriglyne volg gewoonlik ‘n
deterministiese ontwerp benadering, deurdat ‘n voldoende ontwerp spits faktor toegepas word op die
gemiddelde jaarlikse daaglikse stelsel aanvraag om sodoende te bepaal wat die verwagte spits aanvraag van
die stelsel sal wees. Hierdie ontwerp spits faktor maak nie voorsiening vir die potensiële variasie in die
eindverbruiker se aanvraag karakter of die impak van die beskikbare water-opgaring fasiliteit op die
benodigde ontwerp spits faktor van die grootmaat-stelsel nie.
Hierdie studie ondersoek die tydelike variasie van die eindverbruiker se aanvraag op twee grootmaat watervoorsiening
stelsels. Die twee stelsels is geleë in die winter reënval streek van die Wes-Kaap provinsie van
Suid-Afrika. Die data wat geanaliseer is was die maandelikse gemeterde verbruiksyfers van verskillende
eindverbruikers voorsien deur die twee stelsels. Die datastelle het oor 14 jaar gestrek. Die ware maand piekfaktore
is bereken vanaf die data en is in deterministiese en probabilistiese metodes gebruik om die verwagte
eindverbruiker en stelsel ontwerp se maand spits-faktore te bereken. Die probabilistiese metode het gebruik
gemaak van ‘n Monte Carlo analise metode, waardeur die ware gemeette maand spits-faktor vir elke
eindverbruiker vir elke grootmaatstelsel gebruik is as invoer tot diskrete waarskynlikheids funksies. Die
Monte Carlo analise het 1 500 000 iterasies voltooi om waarskynlikheids-verdelings van elke maand spitsfaktor
vir elke stelsel te bereken. Die deterministiese en probabilistiese resultate is vergelyk met die ware
maand spits faktore soos bereken vanuit die bestaande waterverbruik data, asook teen huidige gepubliseerde
ontwerp spits-faktore, wat in die bedryf gebruik word.
Die studie het aangetoon dat die deterministiese metode te konserwatief is en dat dit die verwagte piekaanvraag
van die stelsel sal oorskat en dus sal lei tot ‘n oorgrootte stelsel. Die probabilistiese metode het
goeie resultate opgelewer wat goed vergelyk met die ware maand piek-faktore. Dit word gereken as ‘n
toepaslike metode om die benodigde ontwerp spits-faktor van ‘n grootmaat-watervoorsiening stelsel te bepaal vir ‘n gekose voorsieningsbetroubaarheid. Die studie het ook aangedui dat die ontwerps piek-faktore
voorgestel deur die huidige riglyne te laag is en dat dit tot die falings van ‘n stelsel sal lei. Die studie het ‘n
moontlike verwantskap tussen die gemiddelde daaglikse wateraanvraag van die eindverbruiker en die
verwagte maksimum maand spits faktor geïdentifiseer, nademaal die piek-faktore soos voorgestel deur die
huidige riglyne nie beïnvloed word deur die eindverbruiker se gemiddelde verbruik nie.
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