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Show insulting Engineers L'n-Hjervedly L'n-Hjervedly Condemn the wVork as Planned. K SKILL SHOWN: MUST ABANDON WORK Bjropei' Dam Can Be Put Bower Down, if Right-H Right-H y Built. HSbY 0. E. ARNEY. EyTlie Tribune mfi Idaho, Sept. 15 Tho Big Br irrigation project has found Kjito tho politico) situation in Kfoiigh (he shortcomings of tho Egte land .bonrd. Tho 'Mackay K j:ey to the Big Lost river ir-Kj'stcm. ir-Kj'stcm. It lias beco condemned I Erd of as competent engineers as Er cm tho security of Irriga-flus Irriga-flus nuywhere. j KH. Qumton stands at the head Hhrofesiou on tho Pacific coast. vcurs Mr. A. .J. Wiley has BTitlio head of his profession in flnCr, D. G. 31 mi iu has had wide Hfto'in irrigation matters in the B&Idaho, covering a period of Hq twenty years, without the Kfthint of suspicion as lo his fabilitv or skill as an engineer. Hnnies "Stephenson. Jr., was tho K&necr who is responsible for Eciont contract drawn with the towbriilgc people for the con-Erbf con-Erbf the Mackay dam, and the Kid of laud commissioners, and EOtho governor and chairman He jaw makes tho nominating of-Kitfitato of-Kitfitato engineer, is responsible James Stephenson, ,Ir. H&r of "pood report" Mr., ttephenson, Jr., contributed, as Kgim'cr, to the state of Idaho, Ktlto credit to t he assets of Gov--Hidy who sustained him in of-Hlto'thc of-Hlto'thc Brady state land board. WpCof "ill repute" Mr. James Hod, Jr.contributed as state en-Hostile en-Hostile slate, must be duly cn-Hla cn-Hla debit and consequently be-Bfliabilitv be-Bfliabilitv lo Governor Bradj- and Hitc land .board. Bus' materially affected by this Hlic discovery of the inefficien-His.faultv inefficien-His.faultv ollicial, clothed with Hibt authorit' for so many years, tit once a "tender spot on the get situation in the state of Hj5, filled with legitimate Carey Kts. Idaho stands away up near Huof the stales of the union (hat Bm advantage of tho attractive Kf this timely legislation. Bprtant is the proner innnage-H innnage-H this . portion of the people's H.of this commouwcalth, that in Katfthc readers of Tlie Tribune Hfully advised as to tho entire Bithcwork attending tho Mackay ttioii, the entire report of this Hon1 of able engineers is hero-Bitted hero-Bitted at length: Hfco Engineers' Report. lKUc, Idaho. September 2. 1310. stc Board of Land Commlsslon-IKte Commlsslon-IKte Capitol. Boise, Idaho; Emission of engineers appointed no the reservoir dam of the Big V "Land and Irrigation company may, Ida respectfully submits lHj!n report for your eonsidera- iHmjor the Big Lost River com-Mocated com-Mocated on Big Lost river, ahout Hps! above the town of Mackay. payc a maximum height of li!0 Jliwould impound 170.000 acrc-fect jaLWlth the water standing ten ftlts ciest. The dam Is of tho Itvpc with n spillway in the pfck at the right end, and an rHPy". a l,'imel in tlic rock near f the hase of tho dam at the !.' tho spillway. MSfcens of .Mackay. knowing- that Ry.1 the dnm mlglit result In H&lw lifc.;,,ul Properly In the lac valley, and believing that BJ? rcls Improperly constcucl-K-V J- B- IJPPlncott of Los An-Knorl An-Knorl P"" Us design and mHKVi, , LiDPlncott condemned HWUcultus. and gave it as his rtlie dam, as being built, was IHStLuV10 '"habitants of the 'Htfc. f,,5Vtilliat! owl"5 to the vtu : foundation, it would be im- fKn'n.ni 1111,1 a saf n"3'" of the Up0n any modincation of Mlon was instructed by you to mako a complete Investigation of the dam and to verify nr disprove the charges mado by Mr. Lipplncott. and tho concfus-ions concfus-ions reached by him Copy of .Mr. Lip- specifications are licrolo attached euT ! n,Sm,hera of Ihe commission, consisting con-sisting of D, G. Martin, the state cngl- W?h,0: JU- consuUIng engineer of Los Angeles, Cal.. and A. J. VHcy. consulting engineer, of Boise. Ida afler a careful consideration of the plana m? K11"5 amI a instigation of thrj work itself have reached the same general conclusions as nrrived nt by Mr. JJppIncott regarding tho Inadequ'acv of the plaits and specifica lions, and tho dangerous dan-gerous characler of the WOrk. done In compliance I herewith. '. REQUIREMENTS OF THE PLANS AND SPECIFICATIONS. tl,fCoLe "fIlc words "rlRhf nnd "left" In tixXr r,siu oi-,crt ,ok- nnTf if ?'ans. a"I fpocificationscall for an ?2n .ai" havlnC a maximum hclghl of So1, and a .tor length of 203U feet. 7om 'I8!??, is, 10 hn,ve ;i tQP width of 20 P'1 the up-stream and down-hi down-hi n,J?,ie,S-r The "P-slrcam face Is to be piolccled from wave action by riprap be w ell plowed. Tho sod s to be removed r1 le n,I(,,1Ie ,thlrd of base? and K i?nUV,ler tlle bottom of the dam near the down-stream toe. A line of centv'l?, ,S,t0 bc driven on the fhS hJ,lie ?f lle dain -'necting with Jinrubld ,rock at the r'Sht end and ex-i ex-i 'S dwn t? firm rock. This sheet SSi n? liinn I?0i,.,L Jc,c lhe dam has a u VlVS iLlo,nbe b?dded in a concrete eoro SnJ.. . 0 lop of whlRh ,s seventy feet below tho crest of the dam. This' core t.,,?""r8 A", lhc rock ""ope niTl'e fls Invn lin V? "!1,n l ,,hC P0I,- Wbe,c its level top nlorsects the natural slope ?, l,Jf Kiound. J (;yond the point where , sheerl ?,,,nRs ends, 110 feet hc- Smni5erl,?pif.l ,c (Ul'11' the co,c wal1 's founded in a trench cut six feet .aeon in the natural surface. Bevond the end of the core wall, the only bond be-Lr.nnrtn'0 be-Lr.nnrtn'0 dam and the natural surface n,n by a, Pencil four feet wide on he bo torn and six feel deep, which is to be baek-lillod with selected material, the nature of which is not specified. i lie specifications name three alternative alterna-tive methods which may be used in building build-ing the dam. The one adopted by thc oriiractor consists in dumping from a of m,1'!!1, tW0,,Uy-?vc feet high trains ?,lu: 13 .1?a.d.cd by s,ca,n shovels. The k hrtv ! e lon pllc?d upon tbis method is the rem iremenl that an ccjiial weight ,,'Mar0,;,,al sl,a" 1,0 dumped' upon each tide of the core wall. COMPLIANCE WITH PLANS AND SPECIFICATIONS. "i ;,llL .half complelcd. appears lo have J , 11 " -onformlty wllh the plans fil,ua V.0,,s CXCCI(; lhc driving of i ,n.a,,ccLt.,p,,l"s- which, tho evidence &hows, noilher extends to "firm rock" a.'?, "c depth indicated on tho plans. c.itions Is of little consefiuencc, however compared with tho fact that tho sleet r.neJs mM entirely under about lfiOO the sh'n' , T1,e p,ans s,,ow tba "I' sl?Ps at a point where tncie is sun near y a maximum bond upon the base of l.lie dan" d the !l,mal!lratir of, 1,10 ,nncr sectIon of tnc dam may have boon si ghted. but the complete saturation of this mass of gravel aitd boulders would have made Utile improvement im-provement In Its quality. The method of ? ha,m.? l" ""Jterlal. both In th bod? SLVi e d k"1 aJld 111 tne eentral saturated f?l : ,by duniplnsr from a trestle 25 feet high, xvhich Is called for by tho specifications, effects an almost perfect separation of the materials instead of the mixture which Is called for by tho specifications, speci-fications, so that It would ho impossible to comply with one provision without violating the other. It therefore appears to -us that the fatal defects in the work are clue to tho plans and specifications rather than to thc construction. REMARKS UPON THE SPECIFICATIONS. SPECIFICA-TIONS. Mr. Lipplrcolt has said in his report tnal the specifications are misleading. ve consider that he has been very mild in this statement. They are not only misleading, they are Incomplete, indefinite, indefi-nite, contradictory and erroneous. They are silent where they should specify, and, when they specify, they sometimes specify wrong methods: they are Incomplete, Incom-plete, because they omit some of the most important data necessary for the successful construction of a. dam, as, for instance, the method of mixing the various va-rious ingredients or which thc body of the dam and the puddle core is composed. com-posed. They are indefinite, because thev do not define; ns. for hihtance, where "thev Bpcak of the "material" of which the puddle core is to be composed without mentioning what It Is. And both Indefinite Indefi-nite and erroneous, in slating that "there is an Impervious bed of clav and gravel" underneath a bed of gravel (about 2000 feet long) "averaging about 15 feet in thickness." They should have stated thc maximum and minimum depth of thi? layer of "Impervious clav and gravel" and its thickness. Obviously, if it were only an Inch thick, one would not take lhe risk of founding an fmportant structure struc-ture upon II. Again, when they say that a "trench Is to. be backfilled wllh materia!" ma-teria!" without specifying what this material ma-terial Is to bc, or how It is to be placed. They are contradictory when they call for a method of placing the material in the dam which shall Insure a mixture of the materials, and specify a method of placing it which will effect a separation separa-tion instead of a mixture. Again, where they specify "earth" as a "mixture of earth and gravel containing over 10 per cent of earth" in par 4. clause -I. sec. 11. and "gravel" as "all gravelly material" containing 90 per cent of clean washed Kravcl In the very next paragraph. According Ac-cording to the specification;, If the material ma-terial conlainod exactly JO per cent of earth and 00 per cent of gravel. It would be "gravel:" hut. If it contained 104 per cent of earth and 91 per cent of gravel. It would be "earth." One would natunilly suppose It was still "gravel." Tills classification, clas-sification, although not absolutely contradictory. con-tradictory. Is so near it as to show that tho writer of the specifications had no clear conception of the difference between be-tween earth and gravel. Earth and gravel, properly mixed and placed in an earthen dam. will make -a watertight water-tight structure; but material containing 00 per cent of gravel, dumped promiscuously promiscu-ously In a heap without, any attempt at mixing or proper compacting, will not do so. The specifications relating to the formation for-mation of the dam are entirely Inapplicable Inap-plicable to the material of which this dam Is competed. Willi Its aggregates properly segregated nnd dispoped. this material might have been built, into a waler-JIght. structure, and It. Is posslblo thai the foundation might have been 1 rendered secure from thc passage of large I amounts of water through or under It. but these things could not. ami have not, been done under these specifications. DAMSITE. The fie'.cclion of thc damsilo was an unfortunate one. To found a dam expected ex-pected to retain water to a maximum depth of llf feet on anything but a sure foundation is a hazardous experiment. The principle laid down by Mr. Lipplncott Lip-plncott that such a dam should connect with bed rock, or at least, with a con-llnuons con-llnuons liiipermcable stratum connecting ! with bod rock, is a safe one. H Is t:lcd that s'oundlngx. made with a chum drill , ami H-Inch pipe, showed a hard resisl-I resisl-I ing htrntum at depth of 11 to 11 feet below 'rhot bottom. There Is nothing to show, however, in these soundings how deep and continuous thc stratum is, nor what is below it, and the onlj- inference that could safely bo drawn from such soundings would bc that the drill struck something hard which might be a boulder, boul-der, or might bc a hard plug of material formed by the churning of the drill and to compacted as to bo Impenetrable, cr a hard stratum of unknown depth which the drill could not penetrate. Such soundings sound-ings aro of little value in determining the nature of the material on which thc dam Is lo rest. On the other hand, evidence collected by Mr. Lipplncott, and corroborated in a general way by a letter from Mr. Elliott, El-liott, a civil engineer of Salt Lako City, shows conclusively that no continuous Impermeable stratum exists at thc depth stated, and thai dug pit3 and driven wells passed through an impermeable stratum at a much greater depth and penetrated bodies of quicksand ' which tlowed so rapidly into thc pipes that tne work had lo be abandoned without reaching bed rock. It is .slated by the engineers of thc company that the sheet piling for about thirty linear feet Is driven to a depth oi thirty-two feet, and the remainder onlv lo a depth of eighteen feet or less, tho statement being that it was driven to "refusal." The sheet piling used was entirely too light for driving In gravel, being only six inches wide and one-quarter inch thick, weighing about eleven pounds per linear foot, and, moreover, it was driven with a hammer weighing only 1700 pounds. For driving througn gravel and boulders, such as found m this foundation, a twelve-inch steel pile, onc-half-Inch thick and weighing not less than forty pounds per linear foot, and a 3000-pound hammer should have been used. If this had been done the depth Of "refusal" would have been verv different. dif-ferent. Nothing is said in the specifications specifi-cations about the size of the piling or thc weight of the hammer a serious omission. omis-sion. It Is well known to construction engineers engi-neers that it is a difficult matter to make the joints in steel piling tight, and, naturally, tho fewer joints the better bet-ter for the Impermeability of thc curtain cur-tain formed with tho piling. A larger; section with fewer Joints would have presented pre-sented fewer scams through which leakage leak-age could have taken place. As now driven, water is probably passing tlirouch and possibly underneath what should be an impermeable curtain driven to an impermeable stratum connecting with bedrock- About two-thirds of the dam rests upon the gravel cone of Cedar creek, into which the water from Cedar creek, at all times except in flood, has been sinking for ages. The dam is composed of precisely pre-cisely the same material as that of which the gravel cone is composed, and It may well be asked. "Why, If the waters of Cedar creek have been sinking and disappearing into this gravel bcu for centuries, will not thc waters of Lost river, when piled up under head, do tho same thing?" Thc only known answer to this is, "They will do so unless prevented pre-vented by proper means." To facilitate the entrance of the water into this gravel bed, great borrow pits, exposing large areas of clean gravel, have been excavated exca-vated in thc reservoir site near the dam. in places thc water, when at its maximum maxi-mum level, would be fifty foot deep over large exposed areas of gravel, and it. Is safe lo assert that thc water Is going to pa3s freely under thc dam and cut-off trench, shown on t lie plans and mentioned men-tioned in tho specifications. We have no hesitation in saying that such a foundation for a dam to Impound water to a maximum depth of 110 feet Is insufficient and Insecure. DAM AS CONSTRUCTED. In section 2. division 1 of the specifications specifi-cations tho dam is defined as an earth dam, and in division A of the same section, sec-tion, "one of the definitions of earth is a mixture of earth and gravel containing contain-ing over 10 per cent of earth," and this Is what thc entire dam, as now constructed, con-structed, is composed of. Jt is too late to .specula lo on what the writer of these specifications really meant by those definitions, defi-nitions, because, there being no other definitions in the specifications of the material to lie used In the dam. tho contractor naturally went ahead and built the dam of this material, which might bo said to bc a mixture of earth and gravel containing over 10 per cent of earth. 1-Icro is a grave defect in thc specifications, specifi-cations, and, "lo make bad worse." thc method of depositing thc material is clearly outlined for the contractor, allowing al-lowing him to dump thc gravel from high trestles, thus grading it from fine to coarse in a vertical direction downward. If this material could have been graded from fine to coarse in a horizontal direction di-rection down stream and placed in the dam in a skillful manner, an impermeable dnm might have been mado of this material; ma-terial; but. to specify that it should be dumped from trestles on the lower and upper toe of the dam was merely lo make a series of blind drains through the dam and that is precisely what Is dohe now. as water passes freely through the dam (although the reservoir is almost empty) and there is practically no pressure upon the dam. It may well be -asked what would happen to this dam if lhc reservoir reser-voir above It could bc filled with water to a depth of 110 feet, exerting a pressure of nearly fifty pounds to thc square inch. There Is no provision In the specifications specifi-cations for making lhc dam tight, but great reliance seemed to have been placed on saturating a portion of the same material used for the body of thc dam, nnd thus creating so-called "puddled "pud-dled material" In tho center of thc dam. There is no definition of "puddle" or "puddling material" in these specifications specifica-tions a fatal omission. Jt is vaguely alluded to as "thc material" in clause S of the fourth section, and thc only inferenco that we can draw from this definition is that the material alluded to Is that of which the. dam is composed, namelv: gravel with 10 per cent of clay. The onlv treatment received by this material ma-terial Is the addition of a certain amount of water plavcd upon It from a small hdse under light pressure It is needless to sav that the result is not "puddle." It is "a heterogeneous mass of boulders, gravel of all sizes, and occasional smnll pockets of flno clay, through which water could pass freely. LIPPINCOTT'S REPORT. Wo have been asked to slate In this report whether we agree or disagree with the general findings in the report made bv Mr. J. B. Lipplncott, assistant chief engineer of Los Angeles aqueduct. Theso findings may bo summarized ns follows: (1) "The tests by sounding rods for Impermeable material In the foundation are misleading." We agree with this statement nnd consider that Biich testa arc of no value for a structure of thc magnitude and importance of the proposed pro-posed Mackay dam. (2) That "tho gravel 'bed or cone i formed by Cedar creek and on which tho greater portion of tho dam rests is pervious." per-vious." We agree with this statement. (3) That, "the sheet piling has not been driven to firm rock" and that the puddle pud-dle wall is not to and Into impervious stratum. Wc agree wflh these state- 1 incnts, because that there Is ample cvl- t dence to uhow that no "firm rock" ex- : ists within thirty-eight feet, of the surface, sur-face, which. It is admitted, is tho great- I est depth to which the sheet piling has ' penetrated; and also lo show that no Im-I pervious stratum exists within six feet of the surface, which Is tho distance shown on the plans for thc projection of the core wall below the base of the dam at lis lpwcst point. (I) That "tho specifications arc remarkably re-markably weak In defining boili the character char-acter of the material to be used in making mak-ing tho dnm and In describing the wnv In which it should lie placed:" nlso thu't in this matter they are not definite and do nol represent good practice. We arce fully with this statement nnd think that Air. Lippincotl has. if anything, been too mild In his statements about the specifications. (5) That "the work was not bclns done even as well as the specifications Indicate." Indi-cate." We do not nulio areo with thl3 statement, as we saw nothing to indicate indi-cate that the contractor was slighting the work - In any way. lie seemud to have done tho best he could under such specifications. (G) "Neither l.ho plans nor tho specifications speci-fications define the length of the core wall." Wc consider that, the profile on center line of dam on drawing x, Mr,, 202. BZ. shows the ends of tho core wall and that lis length is sufficiently defined de-fined on the drawing as 050 feet (from station 11 to station L'0.50), although It Is staled In tho specifications that "the exact length will bo determined as thc work progresses." (7) That "thc puddling is entirely inadequate." in-adequate." We fully agree, and go further fur-ther nnd say that no puddle coro coul.d be found with this material. (S) That "when the water is raised 90 feet or more in tho reservoir, and tho area exposed to percolation largely Increases, In-creases, I'speclally along the left 1300 feet of the dam, this ;ear;age will bo greatly Increased." Wo fully agree with this statement. (9) That "the water Is now passing In a stream under the upper half of tho dam. and that it will pass downward through the envc with very slight pros-sure pros-sure head." We fully agree with this statement, ns we saw the water passing, not only under the upper half, but under un-der the lower half of the dam. and there was strong evidence that It was also passing under the corn wall and through or under the shcel piling, (10) That "the spillway Is cnlirch' Inadequate In-adequate as now planned." Wc agree fully. (II) That "the dam and Its foundation will leak very badly with onlv a partlallv filled reservoir, and flint It will not be successful for storage purposes," We aro of tho same opinion. (l'J) That "thc filled reservoir would, in my judgment, be a serious menace to life and property, to the town of Mackay nnd to tho Lost River valley." We aro of the same, opinion but go further ;ind bellc-w that it would Inevitably end In disaster. (Iu) That "the foundation:; of the dam j art; fundamentally bad, and thc structure thereon I beliovo lo have been improperly improper-ly built." Wo agree with the first part of this statement, and with the second, but only because the methods specillcd necessitated Improper building. (11) That "lhc remedy for thc settler lies, In my Judgment. In finding a more suitable dnm and rosrrvotr site." We cannot fully agree with this statement, as wo believe It nyy be possible to utilize util-ize In some way the work and material which has been expended on tho present dam. Xothing could be done, however, towards the completion of the dam lo its full height until a thorough Investigation Investi-gation of the entire foundation of lhc dnm Is made by means of dug pits, driven wells and, If necessary, diamond drill borings. This is absolutely necessary neces-sary and should have been done in tin; first place. It is possible that thiu investigation in-vestigation may show that it would be cheaper to throw away the work alicady done and seek a new dnm she than to make the picsenl dam safe. (lii) "'J can see no valid good to thc settler .or the state lo bc derived from Its completion." This refers to the dam and, if Air. Lipplncott meant the completion comple-tion of the dam under the present specifications speci-fications nnd met hods, wc agree with him, CONCLUSION. We believe that It may be possible to construct a. lower nn:n nnd utilize some of the material and work done on the present dam In j-uch a way as to impound im-pound wiitcr In l he reservoir lo a depth of T0 feel. This would mocuic temporarily tempo-rarily for the settlers a partial supply of water for irrigating their lands and for domestic- purposes, without endangering endan-gering the lives or property of thc cili-zeno cili-zeno of AInckay or the Lost It I vcr valley. val-ley. Tim plans and specifications of the dam, however, would have lo be carefully care-fully considered and passed upon bv competent com-petent engineer;) experienced In this work. (Slgnr-d) J. u. qiJi.VTOX. Consulting Engineer. Los Angeles. Cal. O. G MARTIN. Slate ICnginccr of Idaho, Boise. Ida, A. .1. WILEV. Consulting Engineer, Dolsc, Ida. Such is tho. I'oiidition of one of Jla-Im's Jla-Im's splendid irrigation i-ro.ioets; ono which is nieril.orio'us. The litiui, I ho wal or, tiio cliuialo. all aro liounlLfiil and ideal. Tlio project avi II Miccecil. 1L cannot lie "jobbed" lu thc ilea Hi. A faulty .stilts engineer lias acted upon it. cither without capacity or by conni ancc; and :t state land board lias ncg looted it and postponed attention to dutv for what was lo them of more important im-portant consideration politics. As for I ho slate land board, the report re-port should condemn evwry one of them to their political defeat. As for the state engineer, James Stephenson. Jr., he might v.'ell transfer his attention to placing a coat of lath and plaster on his neglected profession, other than to pointing out the ''shortcomings' ''short-comings' of tho Idaho correspondent to the Sail Lake Tribune. |