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<br />voir from which the water returns gradually. to the stream in the.
<br />form of sprillgs, foi'ming-, in turn, rivulets, brooks, and creeks that
<br />never existed before the irrigation works were constructed.
<br />Mr, MIClmNER, WeJl, Lhat statement is largely theoreti",,!. You
<br />wou] d not su.y as a practica.l man living au t in that arid region that
<br />much of Lhe water diverted for the purpose of irrigation reaches these
<br />underground la.kes and streams, would you ~
<br />Mr, CARPENTER, Oh, yes,
<br />Mr, Mrcm:NER, YOIl would?
<br />Mr- CAnrENTlm. Yes. The percentage of ret.urn, so far as our
<br />invcs,tigatiOJ11:i have thus fa.r gone, varies accordip,.g to t.he soil ~Llld
<br />topography of t.he country and the particular stri~ of t.he strata un-
<br />clcrno.uth. In other words, the soil is more or less strntified with rock,
<br />and Lhe dip of the rock, or the qultlity of the subsoil hits a great deal
<br />to do with the llmount of waLeI' that retUl'llS back to the stream. In-
<br />vest.i.gations sbow that.. tho re.turn funs from 20 per cent up to a~ high
<br />as 60 per cellt and sometimes more, of the waLers taken a consider-
<br />able distance from the stream. Where t,he water was applied imme-
<br />diltLcly "dj.wmt to Lhe streltm, alo~.z/tI1C river boLtom \ltnds, where
<br />Lhe lands are underlltid with gm~stmt"" the return is much in
<br />excess of tlmt; the only water thltt is lost is thltt which is lost by
<br />evaporation in the short time the water is exposed at.. the surface and
<br />through plltnL cxlmJation Itnd other like ch",nnels,
<br />The CUAIlIMAN, When you first put the water on Lhe Iltnd, it ta],es
<br />quit,e It long time for it to soltk through tlmt bnd, does it not'?
<br />Mr, CAHP];N'l'En. Y cs, indeed, Mr, Clmirmlt'L The full e!fect of
<br />the rc(.urned supply is not manifested in lllany districts for as high itS
<br />10, 15, or 20..;u>ltrs ",Iter the iniU,,1 appliclttion talms pl"cQ,
<br />Mr, WidseB'; the noted authority on soils "nd application of water
<br />Itt the UnivcrsiLY of Utah Itnd now, I believe, the president of that,
<br />institution, in his vn..ltmble work, says that for ordinary calcula-
<br />tion it may be said Lhat one.half of the earth mass is air; in other
<br />words, it is mltde up of voids, So that if you take It tumbler full
<br />of soil, for cxample, iL would be much like a tumbler full of marbles,
<br />aud one-hlt]f of the space of that tumbler would be occupied by
<br />solid mlttter and one-lmlf by voids, As the water pours upon the
<br />surfltCC of the ground it nltturally pltsses down through Lhose voids,
<br />accumulates below, and raises the water plane as it eXIsted in nature,
<br />so that if the water plane. were raise.d over .a"eert.ain area., 10 feet,
<br />for example, over whitt it originltlly WitS, ~ rough figures ....
<br />~ 1~ i .&.1 r t you would have all underground reservoir of 5 feet
<br />in depth of deltr waLer, This water, of course, is added to,.,,~Fh
<br />yea.r by efLch year's a..vp.lication, and it passes out below ~'. rhe
<br />subtclTanean ehannels~ 6l'eeks, and brooks thltt I have menUoned,
<br />Probltbly the most exhltustive study ever m"de in the United
<br />States on this subject is jnst beiug coneluded OIl the South Platte
<br />Rivcr, The South Platte River is what we know as a disl1ppeltring
<br />river; that is La say, it increased in flow from its upper sources,
<br />the SIlOW banks in the Illountains; it increased in flow as it pro-
<br />ceeded out toward Lhe foothills bevond, And when it went into
<br />the Plain~~l~tlltntic slope,,9Jitlie Great Plains area, it received
<br />no more contributions~ it gmdually, under natural condi-
<br />tions, lost itself in the sltncl, so thltt in the month of August of each
<br />year, for example, it disappeared entirely within 75 to 100 miles
<br />east of the mountltins; it disappe"red, as far "'s visible flow of the
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