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<br />incurring additional costs. These alternatives Include
<br />drain installation, ditch lining, land leveling, deep
<br />plowing, planllng bed modification, sprinkler and
<br />drip irngation. and increased Irrigation frequency.
<br />
<br />(51 The last alternative is 10 plant salt IOlerant
<br />croPS. An economiC IOH would usually occur since
<br />many sail tolerant crops ordinarily produce a lower
<br />economic return.
<br />
<br />Municipalities could"
<br />
<br />(1) Do nothing and the reSidents would consume
<br />more soap and detergents Of purChase home
<br />softening units or el(petll;'nce accelerated frequency
<br />of replacement of water facilities
<br />
<br />(2) Build central water softening plants
<br />
<br />(31 Develop new, less mineralized water supptie"
<br />
<br />Industrial users could combine mOle elttenSlve
<br />treatment of their waler SUpp1i' with the purchase of
<br />additional makeup water based upon the economics of
<br />prevailing conditions. The required mineral quality
<br />levels are maintained in boiler and cooling systems bi'
<br />.,eriodically <ldding an amount of relatively good
<br />quality water (makeup wated and dischargmg from the
<br />system <In equal volume of the poorer quality wilter
<br />(blowdownl.
<br />
<br />The cost of applying eilch of the alternative remed'al
<br />actions was determ,ned, and the least costly alternative
<br />selected lor subsequent analyses. For mdustrial use, an
<br />estimate 01 requ,red makeup water assOCiated With
<br />salinity increases was selected to calculatl' the penalty
<br />cost, Mumcipal damages were est, mated by calculatmg
<br />the reqUired add,tlonal soap and detergents needed,
<br />phvslcal dam.lges to fJcilities, and the COst 01 central
<br />softening.
<br />
<br />Economic studies wcre Intended to prOVide a baSIS lor
<br />assessing the economic impact of a change in salinity
<br />levels. Water quality, water use patterns, and econom,c
<br />conditions were prOJeCled and appropriate discounts
<br />milde to arrive at representat,ve values. Di,eCt penalw
<br />COHS wert' then aggregated fOI the en!!re im!Jact area
<br />
<br />Because of the ,nteldependence of num..rous economiC
<br />activities, there eXist indirect effects on the r..gional
<br />economy stemm,ng from the d'rect economic impact
<br />of salinitv upon agncultural water users. These effects,
<br />
<br />termed mdlrect penalty costs, can be determmed if the
<br />Interdependency of economlC activ,t.e. is known. A
<br />simpl.. ratio of direct to indirect Impacts was used
<br />based on the EPA study wherein an "mput.output
<br />model" was developed to folloy., changes affecting any
<br />agricultural mdustrV through a chain of transactions in
<br />order to identify secondary or Indirect effects on the
<br />economy slemmmg !rom the d,rect economic costs of
<br />salln,ty
<br />
<br />The economic validity of salinity reduction measures is
<br />dependent upon the extent 10 which damages to water
<br />users are reduced or the usefulness of the waters is
<br />mcreClsed. Similarly, ,"'ater uses ijnd projects which
<br />cau~ salin,ty levels to rise must be considered CiS
<br />ImpoSlIlg cosu or dJmdges on the system which must
<br />lJt' offset by benehts or controls.
<br />
<br />An eXJmple of economiC eflects of salinity mcreases
<br />on iHlgated crops In the Colorado River Basin IS
<br />described below.
<br />
<br />Po.Chu,1Il Sun's 1972 ,tudy: provld<:s ij means of
<br />..stlmdtlng the d'lect ~aliIllIY effecl per mg/1. Utilizmg a
<br />regional economiC model for 469,200 acres results In
<br />an estimated $16 per dcre reduction in net farm
<br />'flcome or a lJenillty effect of 5 cents per mg/J pel acre
<br />per year.
<br />
<br />The Lower Colorado River Basm was diVided mto three
<br />study areas Southern Callforn,a, Lower Ma,n Stem,
<br />Jnd the Gila ared_ Withm these ~tudy areas, irrigation
<br />districts or BUleau 01 Reclamation projects were
<br />identified as representative and for which inlormat,on
<br />regard,ng crop value was ilvailatJle_
<br />
<br />A summary at the estimates for each area is given In
<br />Table 7. The total direct salinity impacts are 566,900
<br />per mg/) on an annual basis fOI 1,076,800 acres or an
<br />Jverage of 50,0621 per aCle !Jet mgil per year. The
<br />mdirect effects were estimated to be 62 pelcent of the
<br />direct elleets. The total Impact QI salinity upon the
<br />agriculturill users 01 the Lower Basin is estimated to be
<br />5108,400 per mg/l per year ,n 1972 dollars.
<br />
<br />Household damages due to salinity have been estimated
<br />lJy a number of researchers An anai' of the calculated
<br />(;O,ts IS shown in Table 8. The Orange County and the
<br />Black and Veatch studies are the mas! complete of
<br />those available. From these t.vO studies and other
<br />information available from various salinity reports, an
<br />estimated valu.. for each of the household items was
<br />
<br />:Sun, Po.Chuan, An Economic Analysis of the Effects of Quantity and Quality 01 Itflgat,on Water on Agr,cultural
<br />Production In Imperial Valley, CalitOlnia, an Unpublished Ph.D, Dlss.ertJtion. UnlverSlty of Cal,lorn'a, Davis,
<br />1972.
<br />
<br />31
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