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Description:
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Conventional water treatment facilities are the norm for producing potable water for
U .S . metropolitan areas . Rapidly -growing urban populations , competing demands for
water , imperfect water markets , and uncertainty of future water supplies contribute to
high interests in alternative sources of potable water for many U .S . municipalities . In
situations where multiple supply alternatives exist , properly analyzing which alternative
is the most -economically efficient over the course of its useful life requires a sound
economic and financial analysis of each alternative using consistent methodology . This
thesis discusses such methodology and provides an assessment of the life -cycle costs of
conventional water treatment using actual data from an operating surface -water
treatment facility located in McAllen , Texas : the McAllen Northwest facility . This
facility has a maximum -designed operating capacity of 8 .25 million gallons per day
(mgd ) , but due to required shutdown time and other limitations , it is currently operating
at 78 % of the designed capacity (6 .44 mgd ) . The economic and financial life -cycle costs associated with constructing and operating
the McAllen Northwest facility are analyzed using a newly -developed Excel
2 spreadsheet model , CITY H O ECONOMICS . Although specific results are applicable
only to the McAllen Northwest facility , the baseline results of $771 .67 /acre -foot (acft ) /
yr { $2 .37 /1 ,000 gallons /yr} for this analysis provide insight regarding the life -cycle
costs for conventional surface -water treatment .
The baseline results are deterministic (i .e . , noninclusive of risk /uncertainty about datainput
values ) , but are expanded to include sensitivity analyses with respect to several
critical factors including the facility’s useful life , water rights costs , initial construction
costs , and annual operations and maintenance , chemical , and energy costs . For example ,
alternative costs for water rights associated with sourcing water for conventional
treatment facilities are considered relative to the assumed baseline cost of $2 ,300 /ac -ft ,
with results ranging from a low of $653 .34 /ac -ft /yr (when water rights are $2 ,000 /ac -ft )
to a high of $1 ,061 .83 /ac -ft /yr (when water rights are $2 ,600 /ac -ft ) . Furthermore ,
modifications to key data -input parameters and results are included for a more consistent
basis of comparison to enable comparisons across facilities and /or technologies . The
modified results , which are considered appropriate to compare to other similarly
calculated values , are $667 .74 /ac -ft /yr {2 .05 /1 ,000 gallons /yr} . |