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<article language="en">
	<journal>
		<journal_title>Drinking Water Engineering and Science</journal_title>
		<journal_url>www.drink-water-eng-sci.net</journal_url>
		<issn>1996-9457</issn>
		<eissn>1996-9465</eissn>
		<volume_number>1</volume_number>
		<issue_number>1</issue_number>
		<publication_year>2008</publication_year>
	</journal>
	<doi>10.5194/dwes-1-27-2008</doi>
	<article_url>http://www.drink-water-eng-sci.net/1/27/2008/</article_url>
	<abstract_html>http://www.drink-water-eng-sci.net/1/27/2008/dwes-1-27-2008.html</abstract_html>
	<fulltext_pdf>http://www.drink-water-eng-sci.net/1/27/2008/dwes-1-27-2008.pdf</fulltext_pdf>
	<start_page>27</start_page>
	<end_page>38</end_page>
	<publication_date>2008-09-25</publication_date>
	<article_title content_type="html">Importance of demand modelling in network water quality models: a review</article_title>
	<authors>
		<author numeration="1" affiliations="1,2">
			<name>E. J. M. Blokker</name>
			<email>mirjam.blokker@kiwa.nl</email>
		</author>
		<author numeration="2" affiliations="1,2">
			<name>J. H. G. Vreeburg</name>
		</author>
		<author numeration="3" affiliations="3">
			<name>S. G. Buchberger</name>
		</author>
		<author numeration="4" affiliations="3">
			<name>J. C. van Dijk</name>
		</author>
	</authors>
	<affiliations>
		<affiliation numeration="1" content_type="html">Kiwa Water Research Groningenhaven 7, 3430 BB Nieuwegein, The Netherlands</affiliation>
		<affiliation numeration="2" content_type="html">Delft University of Technology, Department of Civil Engineering and Geosciences, P.O. Box 5048, 2600 GA Delft, The Netherlands</affiliation>
		<affiliation numeration="3" content_type="html">University of Cincinnati, Department of Civil and Environmental Engineering, P.O. Box 210071 Cincinnati, OH 45221-0071, USA</affiliation>
	</affiliations>
	<abstract content_type="html">Today, there is a growing interest in network water quality modelling. The
water quality issues of interest relate to both dissolved and particulate
substances. For dissolved substances the main interest is in residual
chlorine and (microbiological) contaminant propagation; for particulate
substances it is in sediment leading to discolouration. There is a strong
influence of flows and velocities on transport, mixing, production and decay
of these substances in the network. This imposes a different approach to
demand modelling which is reviewed in this article.

&lt;br&gt;&lt;br&gt;

For the large diameter lines that comprise the transport portion of a
typical municipal pipe system, a skeletonised network model with a top-down
approach of demand pattern allocation, a hydraulic time step of 1 h, and
a pure advection-reaction water quality model will usually suffice. For the
smaller diameter lines that comprise the distribution portion of a municipal
pipe system, an all-pipes network model with a bottom-up approach of demand
pattern allocation, a hydraulic time step of 1 min or less, and a water
quality model that considers dispersion and transients may be needed.

&lt;br&gt;&lt;br&gt;

Demand models that provide stochastic residential demands per individual
home and on a one-second time scale are available. A stochastic demands
based network water quality model needs to be developed and validated with
field measurements. Such a model will be probabilistic in nature and will
offer a new perspective for assessing water quality in the drinking water
distribution system.</abstract>
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</article>

