Document wrKjjeb4qeXe3Rn33z1ddL0K6

m ****/>. Sowa'-Wi'^K ~v.$< si^ ss c*. i ;i f-V >*"'V.' rs&y&'?A;& ai imm rSUf! 3ft beUtet Steam for gtntrciptonr ust [hydro"! ! PLANT \ ,c"f" 5"T,PLt]?T; l!"vbull,d!n? I^x"i"s <""*l` "d ,url>i"; '<>. "Oturol-drof. cooling to.., wllh Induccd-drol, center, diesel eshoos! slocks wllh boilers ond their Hocks behind; oll-storoge tanks behind It. Emergency sloroge pond b! !IjJW Prefect History. Although ancient remains indicate cultivation in prehistoric times, irrigation by white settlers began about 1867. but erratic river flow and consequent need for storage mode these efforts relatively ineffective. Under the Reclamation Act of 1902, the U. 5. Government financed and built Roose velt Dam to create storago and regula tion for the waters of the Salt River. Placed in ternee in 1910 and com* pleted in 1911, this project included a complete system of canals and laterals, and a supplemental water supply was made available by pumping plants tap ping underground water. To supply power (or pumping and other project operations, hydro-generating capacity was installed at Roosevelt Dam and at four drops in the main canola, with the necessary transmission lines and other distribution facilities. In November 1917, the project was turned over to the fanners as a going oonctro, subject to payment of the un paid balance on construction costs. They formed the Salt River Valley Water Users' Association (SRVWUA), a corporation In which each share rep resents an acre of land owned. From 1922 to 1930 the Association built Horse Mesa, Mormon Fiat and Stewart Moun tain Dams ond power plants on the Salt River below Roosevelt Dam. It also participated in construction of the Cave Creek Flood Control Dam. The years-1935-39 saw construction of Bart lett Dam on the Verde River and spill way improvements At the four Salt River storage dams by the U. S. Bureau of Reclamation. The mop shows loca tion of hydro plants and the watershed supplying them, while table on p 95 lists essential data on dams and hydro electric plants. Water Syitem. The water system of today Is not essentially different from that of 1939. The Salt and Verde Riv ers furnish the main supply, draining about 13,000 sq mi of mountain water shed varying in elevation -from 1300 to over 9500 ft. The four storage reservoirs on the Sait River form a continuous chain of lakes nearly 60 mites long and, with Bartlett reservoir on the Verde River, will hold 1,954,000 ecre-fl of stored water, enough to cover the proj ect's irrigated lands to a depth of over eight iect. To furnish additional water and to control ground-water table in the farming area, 200 pumping plants are installed. Granite Reef Dam, below the con fluence of the. Salt and. Verde rivers, diverts water into the two main cinals: Arizona Canal serving the north side of the project, and South Canal the south side. Combined capacity will per mit use of all river flow up to 4000 see It. Bartlett Dam on the Verde and Stewart Mountain D&m oa the Salt River regulate irrigation flow. From the two main canals water is diverted to secondary canals and laterals which serve the farms. Annual water use varies from three to five acre feet per acre, depending oa rainfall and crops grown. Power Syitem. In the original dri&i opment, provision was made for ukia|l advantage of the 723-ft Ufl between* (rail features, now provides a total of ftiflOO-hp fiTM capacity. Construction In frequency changers are on the system, one rated at 3000 kw, and the other at efficient generating station. The one-Une diagram above shows how this was done, representing the plant as it is high water at Roosevelt Lake and tiila water at Stewart Mountain Dam to i erate power lor the projectt own and lor its farms. Titus Horse Meaagjj Mormon Flat and Stewart MounUisjl Dams are primarily power dsoitVsI. though they add 373,000 acre ft toilerage. The four plants on the Salt RJvejj hove a combined capacity of 94,500 bp' fed a 140-mile transmission line [irsa\Parker Dam to Phoenix makes 'iwlibls power from the Colorado, and plants of the Central Arizona kfchi and Power Co and Inspiration SCk'pper Co ere also interconnected with ./tSsJ&lt River system. Nevertheless, as |f/isrfU'foecome clear later, additional firm ?pwcr b still needed. 1800 kw. Diesel* pul In. Water shortage in 1936-37 brought home the need (or standby power on (he Salt River sys tem, and in 1938-39 two 7000-hp doubleacting 2-cycle diesels were Installed, then the largest engines put .into serv ice in this country (five Identical units are installed at Vernon, Calif.). Con tinued load growth, however, required today. Cooting-Wofav Hookup. The dleie) en gines now operate with a closed cooling system, served by a natural-draft cool ing tower, with three heal exchangers, for the two engines. Makeup water comes from two sources; wells at the plant and at Indian `Bend discharge into a 750,000-gal emergency storage pond, and (our other hydro plants on flu1 CROSS CUT PLANT canal system In the vslley add 12jOOO^ Isi&ff'. divert large part of the water hp to make a total of 106,500 hp. As a major source of power lo taken Arizona Canal to Crand Canal by state of Arizona, it was natural for "Albert route, the Cross Cut Cana) was Association to dispose of power b _ ,, boil), and since.there was some 100-ft its own needs and those of iu Jpjbetweeo the canals, a hydro plant holders so that today its 1650 miles cij [is .installed in 1914. As built by the transmission lines and 27 lubiUlishij [Bv/uo of Reclamation, the original furnish wholesale and retail power u! LCnss Cal plant had six 800-kw 25-cycle copper componlei, to various pMk; 'factstor* driven by Pelton wheels, utilities, which serve towns la thij* jtfjatu modernization of the hydro plont counties, and to asny Irrigslloa trlcts, which depend on pumped water installation of a frequency changer ijad diesel and steam prime movers for their irrigation. Load Growth. This growth in Impof-, this Cross Cut plant the nerve snd major unit of the Salt River tance of the power phase of operatic^ .SJWOL introduced some new factors Into jPpfc the hydro plant, three of the origl- picture. Load growth tended to bee*^. generators were removed and the independent of the project's Irrigati8'- ..`rJpsce made available was used for in- development program and new requbj^ iiSU4tiD a ^d>00-kw.ccnerftior driven meitta of service continuity . * hands wheel, better suited for the posed. The need for firm power bees1 i*5g|d conditions then the original acute In 1937 and since that timeb hua and of a 9000-kw frequency been a more or less continuous ppirob-J This, conversion unit became lem. The Cross Cut plant, lo be5 dAftS *n 1940 when the Porker scribed In some detail because of U bought 30,000 lew of 60-cyele it?j^rrer to tho Cross Cut bus. Two other that these 5000-kw units serve as baseload machines practically from the date of first operation. They have operated nearly 80% ol the hours since their installation. Continuons preventive maintenance has kept them on the line for these long periods without major overhauls until now. Both engines hAve just gone back into service after thor ough reconditioning. Steem IntteHottou. By 1940, an even greater need (or firm power existed end It was decided lo build a steam plant at Cross Cut. Under the general direc tion ol Clyde R.-Williams, Supt of the Cross Cut plant, C C Moore Co de signed and installed ' three outdoor 100,000-lb-per-hr boilers end three 7500kw turbine-generators in a steel-frame structure extending the building origi nally housing the two diesels. Choice of diesels and steam was largoly dictated by circumstances at the time of the installations, with quick delivery paramount. It then remained lo integrate these units with the existing hydro plant, lo make on effective and and water is taken from the canal at the hydro-plant penstock. Makeup' Is screened and eond-fillered before ad mission to the towers. Circulating water for the steam-plant condensers normally cumes from an induced-draft cooling lower, but can also be pumped from the tailrace of the hydro plant by a sep* . arete set of pumps. In summer months, when the cooling towers become less effective under, high wet-bulb condi tions, both diesels and steam condensers are cooled by canal water, which is avsllable at lower temperatures. Water discharged from the condensers passes through a waterwheel at the tailrace ele vation; power thus generated ' offsets about 70% of the extra pumping in volved. Boiler Feed. Makeup water for the ' steam plant is drawn from the storage pond and sand Altered end aoftened. It then is evaporated and the distilled water stored in the boilerbouse. A sec ond evaporator draws from the distilledwater tank to. supply the bollere. Using now mainly canal water, which is betier 92 (356) POW6R -m J^?W|r juni l94B 1)57) 9) i*`-l > iisS Ml .vs l it;' jr,*-' -J Vd ,t;.\ 'jV'-'-j a