ROMANCE OF WATER WORKS

Dominion, Volume 13, Issue 202, 21 May 1920, Page 3

ROMANCE OF WATER WORKS

« SOME «BEAT AMERICAN ' SYSTEMS CITY ENGINEER'S OBSERVATIONS In the course of his report oil his last yenr's trip abroad the City Engineer (Mr. W. H. Morton) paid a good deal ot attention to water supply schemes. On this subject he writes:— The infinitude o£ soma of the watersupply schemes in the United States of America is such as to lw hardly understandable bv a resident of this city who has not made inauirios in. connection with the matter. Four particular watersupply developments of the size and nature referred to are:—The metropolitan water-supply system shared by Boston and the neighbouring cities, and wh.cli has been in operation for some years; the Owens Eiver supply system of Los Angeles, recently completed and partly put into operation.; tho Cntsbill 6ysteni for tho supply of New York, now practically completed; and the Heteh-Hetehy Fcheme for Snn Francisco, work on which is now in progress. , Of the above I had the bfst opportunity of ascertaining the extent of the Los Anw'le? and San Francisco .schemes. At present San Francisco receives its supply from n private waterworks company. An idea of the magnitude of the undertakings is given by the following figures. On tiie Los Angeles scheme the entire development from the Owens Eiver intako In the terminal receiving reservoir near 1> Angelas has a total length of 223 miles, including ninety-seven _ miles of lined and covered conduit, forty-three miles of tunnels, and a . reservoir _ eight miles'in'length. The aqueduct is desisned foT <i enpneity 260. miJUon lons dailv. which can be used in transit to develop electric power averaging.'4fl,ooo. iiorse-nower. The cost to date w about ■fo.'iOO.OOO, and water is now being delivered. but no power has as yet been commercially developed. • Active work on permanent construction was begun in JNovfinber: 190". and in November, 1913, tho first water was delivered at tno tenninal An. important point to be remembered in connection with such works in thn necess:ty for careful and thorough .preparation. The chief, engineer of the. nroiect emphasises this in a the' undertaking: ".We spent altogether .eROO.fIOO in getting ready [or the job. That was the most trying time m the; existence of the-work. Wo were all fearful that some d'l'gent taxpayci might arise and say: 'Here vou have snont and you haven t done b dollar's worth of work yot, which would have been absolutely . true. • "So far as the. actual construction of the aqueduct was concerned there has not. been ii dol'nr'-- worth of worlv done when we had ,».« spent It was always impressed on me all through my life that it paid to get a good 'ready on I didn't want to see the work start until it wns completely And ypu. could not' properly start without doing., that." More than a-year was spent in preliminary investigations and surveys, and then a board of consulting enßineerj? was appointed to examine the. grniiml. review the work done, ■ and estimate, the cost of construction and time required, and suggest changes. , The Catskill development of Vw . York ndd= 250 niillion gallons daily .o the ci v suonlv. The water is impounded m the tßhnknn reservoir, which has a capacity ceTentv-five" "liles through the anueduct The Kensico reservoir has a npf, y to New York if the Catskill aqiieIte izs? A-sag „kra"lto» »« tanmlp"'" l 5; .'and "will take eiclit years for construe the Hetch-H"tehv scheme ;at San (''rancisco 'the aqueduct in the iniHal development will consist of 88 miles Of ■iiSs to r,i feet in diameter and ,G0 mTle's of tunnels. 10 to l»i W.n d,meter, a- total .length of 154 to. the' boundary line of ?an » County. After the first 10 mile» ot anueduct is completed the water will be dropped 1300 feet through an electric generating station, where an nj« nse <£ • fifi.OOO horse-power will .be available. An ultimate consumption m eisco Hay region of 400_ million gallons daily from this source is contemplated, and the. aqueduct tunnel ' above t|ie nowcr-housc is designed for this quail-, titv so that the full amount of. water may be diverted and used in the powerhouse at once thereby safeguarding-the city's water rights, and giving a maiketaliie asset at an-early, stage of developriient. O'her tunncla ,and pipes below the power-house are not .being made of the full capacity at present, in order to reduce the cost of the initial develop: ment. . - Both the Heteh-Hetehy and Los Angeles schemes, it will be soon, are not. merely for- the supply of water, but for. the davelopnwnt of hydra-electric energy.- and in both instances immense ounntities of water are required for irrigation pui poses owing to the scanty rainfall which in IjOs Angeles averages only 13 inches per annum. It was found that in the Lake district, many cities drew their water supply from the lakes. In the case of Chicagotunnels are driven under,the bed of Lake Michigan, and the water is pumpeddirectly through these tunnels into the mains.' Similar methods are adopted in other cities. In Toronto, however, a complete filtration plant has .been provided, and through this the water passes licfora being supplied ti the city. The magnitude of the lakes is hard to realise, and at first it would, appear that with the discharge of drainage into them and the amount of shipping which is now borne upon their waters—a sufficiently" pure supply might not be obtainable. Owing to the great extent of 'the lakes, liowevev. no such difficulty seems, to be experienced. In the cast of Chicago, a difficulty has been found, but more part'cularly in connection with the" water that is used Cor diluting the sewage in the cana! known as the Chicago IliVer, whic;h connects Lake Miclvgun and the Illinois Kiver. This canal has been construct,id principally as a drainage channel, and it conveys pra'cticallv tlie whole of the sewage of Chicago into tho Illinois Eiver. and subsequently into the Mississippi. In orde:- to dilute the sewnge and prevent complaints, an immense quantity .of water flows from the lake,' and. the Federal Government has recently culled upon the Chicago 'authorities to kmsidernbly lessen the amount of water so diverted. This presents a problem of great magnitude and '.difficulty, and evidently must result in a sewage purification plant on a very great scale being insulicd. There is another aspect of the ease, probably in comiecf:dh"ivitl (lip amount of hvdro-elcc-tric power supplied from Niarara, as by a treaty between the United "States and Canada an agreement was come to some years ago regarding the quantity of wate : - which might be diverted from above tho falls lor hydro-electric, power. The quantit.v of water which is drawn from l.ake: Michigan mid passes through the canal referred to must diminist to a great extent the amount of wafer th-i'l is _ available for the United States at 1^ nra ,' ..Thus -it is not difficult ■|- •seo pioixib.o reasons nctuating tho Federal Government in renuiring that a much smaller quantity shall be used for s C „ age dilution in the canal, reforreu to."