Table Of Content

WT Replies Sorc Pushing Co. I by ed. basset PART ONE Many fr, rahe nel other fr zedge of and cemtorace a4 1286" on Brook HCN thee Kis IN ast ‘hice the iden sha a aval eet con provide 8 useful puree poner has mevr cert <6 he property Ow ‘or FU, tas Use aejevted a ily. The fact romain hcules, dha anpresive adsanlagee San sping fn Soll watersemce isaltoas, Elecirsny fan by generated for getera uae. for pum mg vitor, and for stnctchy oF emergoney porposer and fo pond tha ie aeully ered cin serve adil 252 trea fon watering Hivesocs bdr tives for fre tigi ia psning pal. de place to fabs Bah bv apse oe a Score Por ean Be nftdincd fim any Msang sisim, em snaier how smal, Whetaer iis desiable to harese this power depenils on Iwi felons. Ft des wer wal Uh gear coun, even anche late sumer meni? Seonad, doce enough witer How lev mike the hammessing of i eonomiga ly sound? The fast focter vf sntere, know Tivthe properey maer by observation: the cond may be fdeerminel ty Seiple messremeis Harnessing the Small Stream Resriated cow of Werors cas teat arin of puwer alg werth teseloping? There isu ths coualry 3t Kis one Sater: wheel manvisciurer who “ses a Hine of smal -capocMs Unis. aed els company gmallest hyralortis a8 Aleselope 1/2 iran, Prom thus ean Be nterrd than Ihis company's experience 8 aot economically wise 18 harness scam tr will new deve a teat 30D wate Lepondly #1 the amitchbvurd. Hall § lott will Bgl 10 fate sized Tamper supply 2/3 hp. Spires 9A. decpevslt pump. vith tie igure in rind ara criterion, the render can mneke a peliinary eecunhiiannss ol tie scien power aeallzhle on He propery. The chances are Be SSI Re suspvinad; even seemingly insgaificat sear ‘in iotver many tines (ie enn “The power syalahte my Pe ie af a water whee! (hat before dadusions tae inet cenwies in the shel and generator’ is expressed im this formula 4200 Hp. Hews @ fe the cubic ect of water pring tenngh the shea inne tinue: Hie the “head” ot vera stance Tier theough which the weer falls: 42 che weight in found of Hea fe of water nd SAME the mamber ands gor mine sa hp. A mumber of methods cust by atch the vorahles O and H can be determined, bor before censoring them. it well to examine ft the te for the dam aed hcl, since Whey il ‘The to un of the dam, as suggested in Fig. 1 should be guveraed by eve princpls, I should be placed whens the Frenowt worl, head ip obtainable, that a, where the Frente fll ocours inthe sorte length uf sear. Such & See is often indicated by natoral salrfl, by 8 000 Spicuounly seep slope 07 by the snitiners of the coer Foe rrond lo ip ss a sple mater of cost dam showld he placed whee it ca be soeles and stb ound the swam water, Thie means, im general, thai Shoold be pled where the ream valley or cat by “The aie of the wacer wheel Fi. 2, ay’ bo ether at the any oe some distance below it The ime toacion i he dnote common, Bing tnpler Yo Build sod elmninating the oad for # pips oF peneerk to deliver nce xo the whee. Dasidvancaes nclode the fat cha the epllway mist Be of sple espa 10 protec the powerhote ia me a Figh Stee, aed the fst that only the "artist ead” — that {reed bythe dary self & aaah. tn eaten where the fond fli anny abruptly below the dam hey dhe divided” Layout may be desirable fori ataty i crenes te hen. Fig. 2 oar teoen rt PY ELS tetany Locat tea “he. Saal end eopenciee apd the et Tall ge NRN NON — 5 & ‘? A ie aes te or ig dan se Bagh a ere a prosige tie Nero 1 EARS Seupy mwrdostund ig wile, Wt hase the dann at he Figure 1 tessting the dam @ The Wheel ‘Typical “dlsided-fat ty dom, hich dd the natural tay artical dara) Bed pre tewheel, with the wheel below the “Aslcr prea calcuon dna bu snd oe We lhe height OF ihe proposed dam. This is eesieted, a2 fle only bythe height of the valley walls a the sity 90d by the malcrlals, equipment. end morc} available for building it.The higher Iie the grester the howd and the Inyger the pon thie ll be created "Pondoge” water loved for 350 times of peak demand — isan important factoe ie wrter power ealulnions Power ie rarely needed 2a hoore day. and exnnrocion nfs dem of aiicent heigl 10 provide water storage wil gaily increme the power avalible a the ime of day required. TK for example, # heel i to be ron for 16 hours a day: ‘df dae Is ble that il impound all wae fosing imo the pond during the idle eight hours, the poser apacay wil be increased ty #0 percent Den neglect to Slicingu.sh baween “ive socsge” — the volume of wale! tepreveted by dhe difference im heigh ofthe splvay lash tones sad the wheel intake — ard “dead storage” — the toalme oF water below ihe tesel ofthe wheel intake, The Former is power banked aun! tite uf mood; the acer it worthless, powerwise, ‘ace the dam and posierhouse are ientaively sited and tne height of the iret ie provisionally set ie ime G0 rewure INE power asilible, Assume shat all waer flowing sa ite streact can Be mage (oy Uneough tne wheel, Which is a fat asrumplion msm slsllaigas. THI Mae (Qin the pier formula) can be Hotcraived by uke “wen acthed" which ‘nsolver um Seeuckngs emporary dam uf comet proponions or by fe “Aho seth” whl 6 toortieally 4 hale Jena ana, dough sil quite saisfactony. “The fost method (Fig. 2) faves the fran Q equats Ax Vx 60 in whch Qs che wolame of water Rowing in cube Fee per tminuce, A the one seaional apex of the seam. i {qunre fect atthe ate and fa the average welocty othe ream at this point, sxpresedl an fe! por secand a So BURRS teeg -* ‘Selec + lenght the seam that sides approsimately parallel and unecbaructed by rocks v shoals fox 4 dbtaner of abogt 100" Siratch 2 1a wre squarely actos the steam nes dhe sldale of his lenght ad mearre the width of the sites herein inches. Male thus deh off on the vite and divide into ten cQual Aivfaioas. Flom the centre poont of each division, measure the depth of the wator i Inshes, Then average the dope F guce by adding each value and dividing by 10. The cross setioral area of the ice, A, ie now seemed hy raliplying this avenge depth oy the width, ad cing the reall hy 144 in ohtin the answer a9 square feck ‘Your nex! scp in deeming Q is 19 measure the rate ‘of flow Using © steel tape, mark off 2 course stony the hank (ha is 100" tong: the mid-pornt of his course shud be an the Tine where the rons secion was. measored, Sueich wires or eope vl across te steam al each end tthe eeutse, and make afloat by Hiing abette so thai Tides avash Provide it with a pensan! 99 that you can Follow i eaty. Then get che Moar adrift in he mile of| the sceam, timing its progress over the course wih 2810p atch, bepiaming jus when the pennant pases the es wire and Stopping just #5 Ie pasos the setond ‘Male 2 series of rans, averaging the results The speed of he oat feet per seound then the length of the course divided by the average tine. Ths rest is nat resever suilble For immediate vse in the ext tormla, Ssnce met all he water fm Sea Ms 8 F9puly 25 tha in the ceme and near (he wop. Ifyou mulaply te oat seal bythe eoefileent 0.83, che reslcane valu wil serve 22Y iw the flow formula ‘Gaver a inate a he ssn of ae 19 be presenta te hee, you san nv sake a og deter iiaoa Of te horsepewer your siteam can provide. I's worth er phasizing, though that ‘is igure ie meeemariy enya a= Earete a6 the meanrerien» that produced I and tal the over indicated is hot present a he Hee of mencuring [A singlesteam Now vatgeisnot af tell particarly wea Unless cis obtained atthe tie of lowest water usualy io the Tae summer months Moveover ven if you hove farang, ARS som oF Fig.3 Float Method of Messuri bitte << 2, torsegn oe Bt ing Flow Trewored the flow a alckwater time, the gore auld possible be supplemented ty others serured daring Imavimem springeate los, 29 han you caw elclte the fize of sillvay needed to prevent damage to your ia allaion in dimes of high water, Fes # good prastice for backyard engineers ae well as for profesional, (0 rene, erowecheck, ord tert your Imeaturemoats2y all means 3¢ your disposal. Such chocks trill not oly reduce the chance of dappeimment i the final reste but wil alsa permit calculated econawive jh sonstrction and greater efcincy in operation Reture you beg.n even» pectin. aary eosoansizanc® of sucipower or Jour atonenty the ver sopgete Jou secure a loess notebank to he decoued ately to the project. Devel the habi of neatly entering lida a8 ‘obtained, not forgeting to note dates at stream Con <dions st the time measuecmente ace made. Sch record Is a grea help in performing sound calcalainas and producing excllen esl, PART 160: PUTTING WATER TO WORK Measuring the flow of water inthe steam o¢ brook on your property i the Lape fis! ep in plaonans 9 small Tacrpower projet, Tie float method of waking the Tneovuremea! i generally (he east tn perform anc if done catefuly. i accurate enough foe mitt parps, 1 however sirinn 4 slew ge Jow-oter Cate ato. pede the progress oF 2 weight oat the weir meched oF Festiring Row hae a lvanoges. Essay onl of water fioter, 2 weir in a eecangulor nowch or spilleay of Carelaly coutolledpeeorianas located in rhe entre af = feull ccrporary dat To siaple mcasuecients pera the volume af ose 10 be accurately calulated TReore constricting the dam, aveaiee the depth ofthe ate thea: the deat of ce weir woich M in Fig ‘Should equal ths. Sincethe dam need abt be permanent, ‘simple plank nt tongue-aod-aroove lumber’ will sere fdequasely. No voter St ose excep! thqoagh the ei, {so care should te lakon co seal the ends and bottom ofthe ‘ae by enteding plank into the bans dnd below the bed ‘ofthe team, Clay uF loam pudling onthe upstream ade Sill stop mien seepage Be sute the dam is perpendicular (the Now of the stream “The weir should be Tneated in the cene of the dum, wich cs lower edge not ess than I sows che stfae f the ster below the dam. This lower edge shouldbe azcueaiely levslad Both ths end the vertical edger o he wee should ‘be beveled ith te shacp edge upsiecna 1/8™ Maton the bevel ill Keep the edge from beating down, Propoctiot te weie geht Us length Lis mo les than 3M, and target if posite, Drive awake fa the stream bed atleast Supsreaa ora the usin pounding i down unlit x5 lap is exactly Jevel vith she Howom cige of te we. Allow the stream ee each ite manimun flow rheoogh the stir and thes mmeseoe wit 3 ruler the depth in inctes of water over che take. Referring co the table 08 ths pape. you cin now ead the camber of eubi eet por min water Int sich inen nt Lae weir Sith, HE you mulliply he gure ron te rable by L. the reall is We Wola) Amount of water ‘owing in cubic eel poe minus. bien Ie 40 the hore sepoter Iria IT your steam is already daromea, there fs ne ned te constvet anoiter dam Jt to measure Now. C16 gate posse wo employ he existing dum using is splay as 2 Seer, provided tha 3 wacer eat he we pa hough Cheaply, Cymru w wuude ox stad hate 0 64th spillway and sea iit place smugly The coaire af the frame should incorporate a property proportioned cit soteh. As before. M shout seal te depth of the watet owing thenagh the spillway before the weit Is matted and L may in mow vases be hall ce with nF he play "To get an accurate eset of avslabla hwepower ou will azed a precie figure fee H. the bead of waer tat Dill be present. Head may be defined as be vertical fistance in fet from the suface of water dn the pond behind the dant the surface ofthe stream: below the dam i the ste of the wll This gure my be obtained by any ‘ot several methods a ates where adams reac penn and wih saely greater difficulty atthe se 9 on unui bn Measuring a dlference in elevation cam he aug and securately done with an engineer's tansi¢ and kstlleg thd, RUN since aot everyone has access «0 these jae xeunents and since those wha da Would not need instruc tions on 30 simple wl 3s runing level, we'l pass en 10 ther methods, Figure 2 llstites very slnple way of ancasuting a seetical distance. The equipment requiced isa carpemer’s level. folding rule or steel pe, 2 1” by 2 by & board with to edges planed parallels wooden pegs, a tke tnd a Coclomp. These ave em that canbe found in ete cutee eRe BURP E EEG EER ee SE SER SSS) Bpteer or hee areas Ie pie support ‘ c a aa fig. 1. Welt Method OF Measuring Fiow. Mare trouble cotate results. Iti espectally esefl ia skallow streams, (in the Mlont method, his gives somewhat more ues oy if'a dam iy already preset [van ihe sraighnadge het level, verte paic of pegs is reed off and noted suse atthe site Slecied for the water hee eos any home, wad weenlnty any form, Though de thettod com be sotesat tobous Hf he dference io ievaon tr ge fe reat e gp scurte mith Sratbery caren leveling and ean How tn the Sowing shai the case Of peeecnieat dam, Ove of trove mennicncats need 10 cary armond te ge af Tied ne raactes fom rater hun sae fo ta ers poeta to nod coes.thokgh al sf ote int alas ave foo thar wage to determine head Fieaions conte messed rudy bythe echoes sf photertphi surveying Fe hore whoa olay uh So perebbeec its» ample mater Wo tate the reed Peters the fl dod Then sate ue equeed carson Sine det feo the decloped.phoegraph. Another seth involves the rots auromsterscthg mercury oF Theol Io nei dlcasne i heuns However ie troiod i well aly here whe end 4 be maces nsdersbe say. ove thn 36" and cat fr Speci techmgucs tho he peal err dos to cepa proportion, Ficop i undstal circumstance Wier, Renmnends thatthe mad Pie 2 be employed imsamuch asi euuves Te spl Caan and wih fedinay coe gives od resi “Wisound figures tor bott Hand O. sour now seady to cleans the ale hongpover of jour foaaloion ‘ihe formula gen previo I ee power is found vo te sulin to mura enpuneing Mth the profes, #97 S55 pa the les sour mene sep sto Astra the fntare of sour power fequiremenms. Here indvidal ridions ave 30 ny sso maton dient to ovine Jpeite procedaret' potle. hose wo suggest fee TEs you should consider in pleaning your power pl Same a he we o wth sallespaiy “nslalstns are uccssuly put iclode circly. powering pumps til nachine josie omer sldemand machin at Seaing a genre saps eect for ether ging Sr poner purpose. The later type of inalaon i of Course he move Rex ad generally wich. Determine, them the ue you propose for jour wer power, 308 Uablate the horsepower seQuitad sfc each em Te the foc of eecre mators ar appliances rated in srpctes ar setts remenher that wars ne vols fies amperes 304 Ghar Td wae are equ tT Bp rom tis ation ne pak ead cas be Steed. this ist su ol the power demands made by afer prose ot cauipment tit a8 prema heise stone tine: Krowing povss ad load you can nove dtc the propiced mtn wil fe on ound Beas. ‘oh ant ace sour avaloie horsepown Ngare dct sie dedecnone sul! rat he nese Tos nt ote whorl wud da tle generators if you, Inna Abe ning ne, Bir ual itallaters ancuine wheel ticncy tn be 9 pr cen. any ans wl bar {Hs bur ihe aspen wll prvi leeway for posse Corman in mesuring H asd Q.Gencetorwceney Sen sn obo 80 pe ont gue ta wl san he Secreta nay caves Fat on he ode Tus seas brant poor muy be eros tl 254-9 or Sate Sane hoes Ae ths age af the gee Ce 46d Jo mull over the onthe sonatas and combinioas rather thin te | rows Sih spe soetocinn on Comer or Phbsing peotenea dam PSB use Ske ‘ee 3 BME ee Fig. 2 Measering Head. With a carpenters level, sienightedge, sud pegs, head can br measured before oF ler the data fs boil. cxumple the decision cequire if xt indicated swachbourd poster well seemingly handle the poth toad ~ hatter to build dan just Large enough wo We this job, or to Pu ‘on suhitaninlly lager Lu handle posible Fara increases in power rsquirements, The former shoice will be cb sivnsty cheaper a1 frst he may aot he 50 the tang can sinve power demands have # way ol growing snd sine #96 rarely stisicory Lo inceeaee rhe atucture of an exile dam, TW the peak toad 3s apparently toe sigh possibilities should be considera Will "pondaee Stored behind the dans cwenight st slack pein “help Du? Con the use of equypaent dispensed with? Is the project necessary a yeursoued! enterprise, nat the Inwepoer chavactristes of ary Season be ignored” A word of sastien on these peanis mae nt De iss Ws i better plan au ingallation de wil poids ore pomer than you need than one whien dicsat supply emvush, Whether in the event tha yeu UECHLS Uo generate ele wieny. toast AC OC fsanothardscisina wera fh cumstances wher: he gunerator must hy "ocated. some distance lium the toad, AC isthe oly einige. or DC (eansmission buses would be woo hign-amouneing in sal insaltsnans to 2 prosbitise perceniage nf switchvoard oer. IE your buildings and esuiprrent are araaly sured to recsive one ype af eutrent tut) sbpyinusy be see jibe ct om the same pe of oer, Yor swamp soe firm is already wired tor battery type lighting sytem, there woud be ee eso to evap the installation én AC. on tbe other band yal are warding fom scratch Fecommend the ote «f BC wherever phssibl. Aa AC. An impulse (rere tmy senes! bs 14 sed bythe force af 11 t feom ehe nore Hea ft hie bes! THe Fest Amerieas ghee toheel Ix turned by Pam ater ailing oem a duct In hich the raacer or ke ty com Bonds navi, rate pone: she tenctlon wheel moved by co propeller is fire a0 a High sured horicantol- As overshot Fey wheel i cole he eight of Oke Fig. 3. Four Types Of Small Water Wheels everater man be elosiy rogubted at oF slighty above Syachronute speed, and. clog repuloion requires com plicated governing equipment bat ws trcky Lo Wail ve €x pensive tn buy, Acampoand-saund DC generac, on the Diher Rend, provider inherenaly close voltage replation eit 8 side speed range; and even a shutwound DC foterator wth @ dcec-schag Geld shooste regulates Sheotd Be sacisactery Selec the ight wheel foe your plant i gerhape the Fiast sep ot your pecliniaary planning. There arc thece [geneal per of Sater whecl — iinpules, sean, and Eriviy — and several Sly common varistioe of e23h {3pe. Mowever, fo anal plant prpores, i iz praible t9 fctow the number down co thaw showa i Fg. 8. Note thee te typer af reiction where. che France ane the Dronalley ate shown. acd bul nae viiey of gravity whoa, fhe nverhot ane "The Impulse at Pelton whel.opersted exchaivly by te force ofthe wile fom the et iplules ions sad tages very slight leakage and frictinn loses su0d. of fetensy under varying flows, an 3 suficientiy Nigh shee speed to drive a generator, His mare censtin te pitng by sreer containing sand, sic, or minerals tha the scattion ‘ype, 1 dssavantages include the fet that Ht eanmat tee all the evsilable need, lnger than a zeae whee Alereloping she same poser, and wi wallow in high fal fvaoes ts be maunted as close co fhe fail water ae posible The reacion wheel ier mle Francis nr propeller ype 's yoned ty ihe fal af water through a et oF pipe In Sia the wheel ndined. ee the moet comput OF th heels for a given poet, usc al uf the avila led, an aperaes at 3 satstacony sped for ditect coupling to 8 entrar. Ws a efficient wheel over a wide range of sondiions. and. con be mmunted at any Sonvenvent heighe sbove il water. Dosadvantages include rapid nrzosinn wth sled waver and relevely high Jeaerge Sd (ition tosses, expectaliy fo smal units Tinaly chore ce uvershot gravy whl, igh sure fed Targriy hy the weit ofthe water and ply Pals. 1 hat gond efficacy under varying fl, and. Uroffected by sand. sl, oF minerals in he wate. Graity hoels tra’ at a low apeed, whieh is undesirable for Geiing a genetatoe oe high sae wacsinery, bur suiable for some pumping and grincing applications Such 2 wheet Wale in igh ler, te ep whee fr given Dover, and will be obairgied hy ice in winter unless hovse PART THREE: DAMS TURN WATER INTO KILOWATTS Concette hough desirable, ke" acessay for dornning a tmall steam, Beavers Inve gtten By for gears thou it Sotable rats las can he found om almoxt any farm. Ls. rovahhewn Timber, enc, masokes plaka, grave, sand, Ind city reall utctal. Choose the materials most feadily ailable oe your property. of the last expensive if you trust alain ther elswleee ‘You will have daverained the Reig and wideh of the dam you will eed t0 convert your areame t power. The omer monihs pede im West tine far tc eaastucsion for then ost Pranks are aL their lowest level and the snier wll not inpede the progress ef work Four asi pes of mall Gams ate show inthe accom panging drawings All ato acapeate in zenerl tothe kind Br mmciale Tkely (9 Be om hand an sso the the head of power deswed “There are two basic paciphs cf desig ro bear ia sind no matter which jo alld, Fis, alam should be sealed Tih above and bebe ils fvadatina to preven the SAE Ra Selec ehh Us. BdPES TAS oondari oe wien brass PEERY Zeon slave, Fig. . The Earth Dam seepage of water tbrough of undoe it Seepage inough & Gam. if permitted. weakens the structure nid oil Ssh Wally brent i; that under dam wil endermice Re foun Anion Then. tow, some theane wat be prowdcd 10 prevent undermining of the dam by wheter that Nowe. x additwn, you should check with your tacal authorities and possibly ile plans Gr yous da wh them. Beneral siperstson conse under the Water Board, Figuee | illvarses the earth daa Sealing tis type af Jam #6 mos important since seepnge wil lcraly corey i say 1 allowed to progress. The veal spt in Beet nd the ddan built croand 4. How tar dient shoal go depends upon the Kind af Sih, A sind foundation. oe iusanee Feauites the seal eo extend daoper han cy” Iplonking is sad, 1 Sail be wll 9 apg &petctee ona rh a ‘A goneealpasira for deposiing the earth ill shown he dang ai ret lo la ‘i age, tlling aid lomping each lapse cll Then pote the waterside santa ‘tom Gresiom By covering i ‘etieg sowel from Brush, Pant tae! on che top and Afowostecam sie tn hold the cath BAL Sar Ey ee ees 21 shoe eS antung on. revgh-pewn timber metres, or emigee ghaotvpsasecwayRtys fies BEES. Lh Le ee igner aaes ses strve ‘oF Fuk, ‘ekrues wy Seatuge senagact ESTE PLR EB § Cer chu Sheet hgh Figure 2, The Framed Dam ‘Such a dar abviowsly cannot ave water spilling ove is ret since ths aclnn Keald wash i atay Uo Suggestions for handling cte ences water are shown The spileay sas be of some meri, such a misonty or planking fesisan to the erosion af rushing Water, and tees ‘ust protec the oper cod ofthe earth dam from spl: Srarer, An alternative sethod of Handling “uno wer is {Fh Gea ies hove a pila. nts means aoe be provided for shuting cheat, A sample cover a the ue Figure 2 shoes the fumed dm, which Bhi cu. be sus built, pastioolrly ov < fain shere tumber in day {rin from loge co planks i abundantly sealable Each frame contiate of une jobt on which Ine surface ther it and and one o¢ more stutt Once the height af te dam it determined, the ive af inci rsnes ai vary depen= dling om the ennvout af he gltey, the frames Incite 3 the tose par being the largest. The frames ae spaced ace cording te the spp the sre timber ocd. hat the Thiter the suracing tke more Suopari needed. ay the tanking surface or reughhewn vier horizon tally and edge iv edge ares the Fees, and bol or spk each in place, Calk the jaints and apply + protective oatiog. Fills pu it behind the downsrenm sie. Bald Plantung seals be Lory, Una ation"| the sina ently of plank sma mde) ihe mich ig oars apn HS for ne sang isda Woutd be moa fesse where lerge racks of field snes abound. ries, conte OF Cinder bist, nd ten chs of Baker since favementace ash exeeCen aes dn sl) 3 frsony ‘perch beck beng al with ore Tang vot erica at fon ay These th diver ut if aorta forthe seh dare ast Bo Tinea. Te placement of eh nda in gle i te fo aly pi of ut ide ts Rete pak Siete the banka te ghonr Orbe he Jy eal pound ie seer ould eum umes hme Sina widh ot nore han 10" Ie ean Umber sed aly ata fame om which tn phe lea arace <T FBenting ay shown ane te droinge Fig 4 the Shar fer usher il depend en he sen he HMenting and aso on hei of the a. ‘Oni ily foundations areconudered in he drawings bet you may be Tetnate shou to hve said rock feuscaton 99 shh co bald mht as wal be the frumdition wil no be axes. Rut seme means Be mramied To uncor che Gen ote eck. Sch 5 with 29+ ‘hoe bls inthe case ter the ccd oe gravy Cam. Fig. 3 The Gravity Dam bret, cpnerene: mueche Pavement er hela Seone. TH VETTE Litewise the dam should be sealed 2 the focktoundation te preven scepage under i ln mat instances il wit be Fouad hes > testi the swidih ofthe silley for excess water 10 some pat cf the rat tenuis of the dam, This wil always be necessny in ‘cise ofan cath dam to prevent washing. Thesp tage Tength of re the trater may be allowed (0 pant over the ea (eamed, gravity, and afth dams. how precaaions shown in Fig. are takes I te dowsteam side ofthe dan oF of the spina is curved hard surface ef wasomiy ov Lines appresinting he nawal eareatre of the water flowing steel tuide ue spillage water 20 i il be dicetee dewestream ithout actually falling. Such a curved splleaysurfoo particularly salsfectory for on eatth dam. Lerge rocks. Ericka or other hatd objeste plored on the dow Sido of» spillway not having + curved surface wl the force of the fewflllng water and prevent erosion “The silly nits simplest form kes the shape of a searaegulse depression ine cre of (he dam H should Unually be large enought cate of ouicieny excess water fo al mngounded ers sl wot lip the lam at any season ef the yeae. This, of course, 8 ule ¢ plese, since accurace determination of pilleay capacity requires s Reed of de oxal sre Urine Byte eeek being choca plus data on the amount of rlefll at alt However, most of us wil now whether ur mo he res scare danni g stays within Hs mks ag the yea docs. then + sale rate ws apply would be to make the aces Utah apitvay coal the eros-rction area of the creek 1 the da when te rial oF jun ready 12 flood. The Grote ts Dlaneated in Fp. & I te stream does food, then citer constuct a dam Dal ina emergency can allow water 4 spi fl engin ‘oF buil se srt of Mouagate fe the ea 0 3 ean be ‘opened when neces. One formeich a fsedgstecauld Take ge ut drat ies teh he Sam shown i Fg t the hugh of the dam you banld ill be determined by the area of mend to be cowted by ie Inippuntel water In general, the ighor she das, she greater the afc ‘covered by water above it ‘All vegeta. beash, stage, and the lake inthe area to be flesded and for about ("around it should be bu ned ont or stewie eared Before the Jim is built TNE eeps down the Breeding af mosquitoes and helps retard pollavon, Ii require the repaltions of some. sa fd 58 wise recaaino even wen me cveted by by, In iddition. all trees mn the area be flowdea should be out reavonatly close to the graund { eatRa ie Na “i Pts Spike flor bert, Fig. 4. The Arch Dam