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<br />chapter 4
<br />ECONOMIC DAMAGES TO HOUSEHOLDS
<br />FROM MUNICIPAL WATER SALINITY
<br />
<br />Corrosion and Hardness
<br />Creating Household Damages
<br />
<br />Starting with Black and Veatch in 1967 pre-
<br />, d" 12 '
<br />VlOUS stu .es of water-quality-related consumer
<br />costs have focussed on damages to water-using
<br />appliances in bouseholds and water and waste-
<br />water pipes, increased usage of detergents, and
<br />deterioration of clothing and other textiles.
<br />With the exception of the Orange County
<br />report,13 these studies related damages to
<br />salinity (TDS) presumably because it was tbe
<br />most widely used measure of water quality con-
<br />stituents that were known to cause household
<br />damages, primarily througb corrosion but also
<br />from scale deposits. To quote Black and
<br />Veatcb: "In a particular water supply, it is im-
<br />practicable 10 determine the specific effecls of
<br />minerals alone, since the effects are dependent
<br />not only upon the relative content of individual
<br />minerals but also upon many other characleris-
<br />tics of the water. Considerations of mineral
<br />effects in this report are only broadly applicable,
<br />and overaU conclusions reached do not necessar-
<br />ily apply in specific situations.,,14
<br />
<br />In 1978 a Southern District report of tbe
<br />California Resources agency stated: "Clearly,
<br />water quality affects the domestic consumer's
<br />water use cost, but because there are many
<br />
<br />water quality parameters which are often inter-
<br />related, it is difficult to assign cost to any
<br />particular water quality {actor."IS These two
<br />caveats, written eleven years apart, reflect the
<br />concerns of many of the chemists and scientists
<br />interviewed during this study. That is, the
<br />assumption of a linear relationship between TDS
<br />and the economic value of various types of
<br />household damages presents a misleading pic-
<br />tUfe of a very complex situation.
<br />
<br />Corrosion.
<br />The eorrosivity of water has been tbe subject
<br />of textbooks, handbooks, articles, and studies,
<br />Tbe most recent, a chapter in a handbook
<br />prepared by Montgomery Engineers,16 slales
<br />that "The rate at which corrosion takes place is
<br />a question of electrode kinetics, which are deter-
<br />mined by a very complex function of surface con-
<br />ditions, electrical behavior, and solution
<br />chemistry," Tbe properties of water affecting
<br />corrosion rates, according to Montgomery
<br />Engineers, include dissolved oxygen, pH,
<br />temperature, velocity, chlorine residual, and
<br />chloride. Calcium carbonate (CaC03) receives
<br />attention in discussions of corrosion but its impor.
<br />tant role is a beneficial one - the formation of
<br />protective scale on metal surfaces.
<br />
<br />The A WW A Waler Quality and Treatment
<br />Handbookl? notes that dissolved oxygen serves
<br />
<br />12 A summary or several previous sludies begins on page 32.
<br />
<br />
<br />lJOrange County Water District, W::II,.r Oll::llity ::Ind Cnn,,"m,.r CO!i:t!i: May 1972.
<br />
<br />
<br />1.4BlaCk and Veatch, Consu~(ing Engineeni, Fronnrnic Fffect.c; of Min~1"31 Con lent in Munirinal Wat,.r Sllnnri~!i:
<br />WashIngton, D.C.: Ofrice or Saline Water, May 1967, pJ. '
<br />
<br />
<br />15California Department of Water Resources, Southern District, r.on""m~r Cn~r.c; ofW::ttn Oualitv in nomeslic Water
<br />IJ!i:e-1 ompnc Area Los Angeles: June 1978, p. 6.
<br />
<br />
<br />16James M. Montgomery, Consulling Engineers, Inc. W::II,.rT1"l"alm,.nt Prinripl,." :lnd nf"!i:icrn New York: J h W'
<br />Sons, 1986, p. 393. - 0 n Ilcy &
<br />
<br />17A . W W ^--"
<br />mencan aler orl..5 n:>o>OClatlon, Inc., W::tl~r OU31ity 3nd Tre::tlment ^ Handhook of Pllhlic W::lI~r Su lie"
<br />Denver, Colorado: 1971, author, pp. 299, 309-311. pp -
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