FRANCIS LEE STUARTPresident

GEORGE T. SEABURYSecretary

SYDNEY WILMOTjJfanager of Publication s

WALTER E. JESSUPEditor

VOLUME 1

CIVILENGINEERING

FEBRUARY 1931

COMMITTEE ON PUBLICATIONS

CHARLES H. STEVENSChairman

HENRY R. BUCKL. G. HOLLERANEDWARD P. LUPFEROLE SINGSTAD

W. L. GLENZINGAdfJerti.ring jJfanager

NUMBER 5

Colorado River AqueductRoute Selectedfor Metropolitan Water Illstrict Requires Pumping

By F. E. WEYMOUTH

MEMBER AMERICAN SOCIETY OF CIVIL ENGINEERS

CHIEF ENGINEER, METROPOLITAN WATER DISTRICT OF SOUTHERN CALIFORNIA, Los ANGELES

. SOUTHERN California, without water, would re-turn to the desert condition from which it has

.emerged. It.r growth has been so great that it i.r nowdepleting all of it.r present available supplies ofwater. Eighteen year.r ago Los Angele.J' com-pleted the Owen.r River Aqueduct, bringing waterjrom the eastern .rlope.r of the Sierra Neoadas, 250miles away. That city, within recent months, hasvoted a $J8,800,000 bond i.r.ruefor extending and en-larging itr Owen.r River Aqueduct to tap the watersof the Mono Basin about 60 miles northwest, and isnow engaged in its construction,

The Colorado River being the only availablesource for additional water, Mr. Weymouth here

THE Metropolitan Water District of Southern Cali-fornia is, in effect, a confederation of cities in thesouth coastal plain. It was organized in 1928

under the Metropolitan Water District Act of 1927,which authorizes the joining together of non· contiguousmunicipalities, or water districts, for the purpose ofdeveloping a domestic water supply. The district isgoverned by a Board of Directors composed of at leastone director from each city, the voting power beingdistributed among the member cities on the basis ofone vote for each $10,000,000 of assessed valuation,with the provision that no city shallhave more than 50per cent of the voting strength of the board. Eachcity has the right toappoint an additional di-rector for each $200,000,-000 of assessed valuationwithout, however, increas-ing its voting power.The enabling act requiresthat the water be distrib-uted among the membercities in proportion to theirassessed valuations, theapportionment to be ad-justed from time to time toconform to the growth ofthe various communities.There are, at the present

time, 11 cities in the dis-

describes the selection of the most adoaniapeous ofthe 60 routes examined, and compares .rix whichwere inten.rively studied. Already more than amillion dol/on have been expended upon investiqa-tions and .rurvey.r of the desert reqions throughwhich the two-hundred-million-dollar aqueduct i.r topass; and it has been characterized as the grecde.r!engineering undertaking in America today.

The material from which this paper wa.r preparedwa.r originally presented by Mr. Weymouth beforea joint meeting of the Los Angele.rsections oj thejourFounder Societie» and fir.rt published in the De-cember 19JO issue of "ASCE," the technicalpublication of the Los Angele.J' Section of the Society .

trict, having an aggregate population of 1,850,000, andan assessed valuation of two and one-third billion dollars.The act provides for the addition of other cities fromtime to time, and for separations. Three new appli-cations have been recently submitted and formally ac-cepted by the Board of Directors. Ratification by thepeople of the applicant cities is necessary before theseapplications become effective. Several other communi-ties have expressed interest in the project. The area,which may be regarded as prospectively a part of theMetropolitan Water District; has a present populationof 2,750,000 and this number must be considered inestimating future demands on the water supply.

UPPER PARKER DAM SITE LOOKING UPSTREAM

For a Mile the Colorado Here Flows in a Rock-Bound Channel371

PRESENT DEMAND FORWATER

In 1929-1930 the Cityof Los Angeles used atotal of 268,000 acre-ft.of water. A portion of thiswas developed from localwells; some of it was de-rived from surface flowsin 0 wens Valley; andsome was pumped fromthe Owens Valley gravels.No appreciable flows, sub-ject to diversion by thecity, went to waste andno water was accumulated

372 C I V I LEN GIN E E R I N G for February I93£ VOL. I, NO.5

in either surface or underground basins. In fact, groundwater levels generally went down. In other words, theCity of Los Angeles actually took more water from itssources of supply than was put back by nature. Thisdoes not mean that the city is actually facing an immedi-ate water famine. There is still water in the under-ground basins available foremergency use, but the volumeof underground water is notinexhaustible, and overdraftupon it cannot continue. in-definitely. We are now, ad-mittedly, in the midst of adry cycle and some relief mayultimately be expected throughincreased rainfall.Rainfall records at Los

. Angeles, for a 50-year period,are shown in Fig. 1. Theprecipitation has been declin-ing, more or less gradually,since 1916. However, therehave been many years with alower rainfall than 1930, evenin the brief period covered bythese records. The 1893-1904drought was more severe thanthe present one. It would be bold to assume thatothers, still more severe, will not occur in the future.It appears that Los Angeles is in a dangerous positionas to future water supply, and it is evident that morewater will be urgently needed by the time ColoradoRiver water can be brought in.

55"

less be placed in a reasonably secure position for atime.The amount of the proposed Colorado River diver-

sion was arrived at by a study of predicted populationcurves, based upon past and present population trendsand comparisons with the growth curves of other large

and progressive communities,such as Chicago and NewYork.From 1930 to 1980, the

contemplated constructionand amortization period, theestimated population increasefor "Metropolitan LosAngeles" is 7,500,000. At thepoint of wholesale delivery,1 see-ft. of flow is sufficientfor approximately i),000people. Therefore, accordingto these curves, the districtwill need the entire 1,500see-It. of new water by 1980.

Ye e r s

".3 ~45:£-5r:::.E 40

1;35~~ 30

~~ 25E.:i 20

~ ~lE~ 10]~

-

, 11111111

11111111

1111111118.24"Average

II 11.2S"Average

II 16.77 Average {

K

12.46"Average5

14.53"Average I \0

I 1111 1+5I J-'Average Annual Rainfall 15.01 Inches

o A1 111111111111111111111111 F

;

50

FIG. 1. ANNUAL RAINFALL RECORD, Los ANGELES

With Accumulated Departures from the Mean

PRELIMINARY SURVEYSCOMPLETED

ESTIMATED ULTIMATE DEMAND

The habitable area of the coastal plain is approxi-mately 2,200 square miles, or 1,400,000 acres. Thecontemplated Colorado River Aqueduct, after allowingfor losses, will deliver something less than 1,000,000acre-ft. per year into local storage reservoirs or, say,0.70 acre-ft. per acre. The Los Angeles Aqueduct, ex-tended to Mono Basin, can be depended upon for per-haps 0.20 of an acre-ft., bringing the supply up to 0.90.Run-off from the 3,900 square miles of the south coastalplain may be counted upon to supply an additional0.4 acre-ft. per acre.Then the total supply, with all prospective impor-

tations, amounts to approximately 1.30 acre-ft. peracre. This is a gross figure, and with no allowance forlosses in handling and distributing. As an irrigationsupply, it is a modest amount, but as a domestic supplyit is low, even for sparsely settled sections, and it makesno allowance for the heavy usage in congested and in-dustrial districts. This allowance will probably beslightly increased by sewage reclamation and perhapsmore notably by "return flow" from irrigation when amore bountiful primary supply is made available.A proposed aqueduct capacity of 1,500 sec-ft., or

1,086,000 acre-ft. per year at the point of diversion,was not selected by the above process of reasoning.But these general statements show that, although theregion will not be overwhelmed by a surplus of waterfrom the Colorado River Aqueduct, it will neverthe-

That the Colorado River isthe only adequate source of water near at hand, whichcan be delivered at a reasonable price, is universallyconceded. Having decided to go to the Colorado tobring the water into the district, a problem of mag-nitude is presented, in the solution of which a vastamount of preliminary work has been done. Whenpreliminary work was first started in 1923, the area be-tween San Bernardino and the river was largely unsur-veyed and the configuration was not such as to pointto any single best line. Accordingly, a general topo-graphic survey was begun, and maps were assembledfrom which the problem could be studied with facility.As an aid in engineering studies and to assist the publicin comprehending the magnitude of the problem, anaccurate relief map of the area was prepared. Thismap is 25 ft. long by 25 ft. in maximum width.When maps became available, a large number of

office locations and preliminary estimates were made.These led to the selection of certain prospective routesfor an aqueduct. These routes were run out in thefield and studied in detail on the ground by the engi-neering forces of the district and by a corps of competentgeologists, with the result that the problem was narroweddown to one line from each of the several possible di-version points on the river. The locations of thesesix lines are shown in Fig. 2.

INTENSIVE GEOLOGICAL STUDIES MADE

The San Bernardino and San Jacinto mountains standas a great barrier between the coastal plain and thedesert country lying east of them. The region whichthe aqueduct must traverse is generally rough andrugged. Mountain masses rise above the general levelof the intervening valleys, which are deeply filled withdetrital materiaL These valleys often form enclosedbasins which are water bearing. The main fault systems

VOL. I, NO.5

THE BLACK CANYONLINE

C I V I LEN GIN E E R I N G jor February I93I

L'EGENO"1'If:5~RI!LINI!~

GR'-'OE TUNNf.\. .••••

GRADI!CONDUIT _

ACTIVf.FAULT,s_

INACTIVE fAULTS-

DUP .•..LLUVIUM i:1Mi,}i\~

are located along, and to the west of, the San Bernardinoand San Jacinto mountains. These systems are gen-erally parallel and extend toward the southeast intoMexico. The most important of these fault lines isthat known as the San Andreas, which traverses fullyone-half the length of the state. Dr. John P. Buwalda,of the CaliforniaInstitute of Tech-nology, character-izes this as the"most importantfault in California,perhaps on the en-tire earth."

Recent move-ments of magni-tude have occurredat several pointsalong this fault,which any aque-duct from theColorado River tothe MetropolitanWater Districtmust cross. I t isconsidered impor-tant that the cross-ing be made on thesurface, and ap-proximately atright angles.

373tunnel, with a low terminal elevation, some flow mightbe taken from it directly for the areas near sea level.In this event, less pumping would be required than ifthe entire flow were lifted at the inlet end, but theactual reduction in cost of pumping would be small,because of the higher cost of power at the outfall. Fur-

thermore, the landbetween the intakeand the outlet isall high above anypossible directgravity flow line,and any such linewould be wholly intunnel. It would,moreover, be diffi-cult if not impossi-ble to construct,beca use it wouldpass at great depththrough several ofthe deep detri tus-filled valleys.

Although thecost of pumpingvaries with condi-tions, for the pres-ent purpose it maybe stated that asum of $80,000 issufficient to buildand forever main-tain and operatethe plant requiredto lift 1,500 see-It.

one foot. Each time the aqueduct is raised one foot,it may be considered as being penalized by this sum.Within certain limits, lifting will bring the line nearerto the general level of the country and the cost will bereduced. Wherever a pump lift of one foot reducedthe estimated construction cost by more than $80,000,the lift was considered to be justified. .

Having decided upon a general elevation for theline, its cost then depends upon its slope. If the fallper foot is great, the velocity will be high and the con-duit may be small. If the grade is flat, large tunnelsand conduits are required and the cost per foot is greatThe correct slope was also determined by the value ofa foot of pump lift, and additional grade was utilized aslong as the reduction in first cost was greater than theendowed value of the increased pump lift.

Taking all of these factors into consideration, a profilefor the Black Canyon line was selected, as shown inFig. 3. This line contemplates a total pumping liftof 1,663 ft. near the point of diversion. The result-ing line is in good location, except for possible difficul-ties in the long 50-mile tunnel between Daggett andSan Bernardino. The San Andreas fault is crossed onthe surface under favorable conditions. A drop of 564 ft.at the terminus is available for the production of power.

FIG. 2. THE SIX ROUTES CONSIDERED

Returning againto Fig. 2, it will be noted that diversions are possiblefrom the river at Bridge Canyon, Black Canyon, BullsHead, Upper Parker, and Picacho, or from the AU-American Canal. A great number of line studies havebeen made from each of these points. The reservoir inBlack Canyon offers an advantageous point for diversion.The water there is at a higher elevation than at otherpoints farther down the river and, because of the largestorage volume, would be of first class quality, entirelyfree from silt. The best location of a line from HooverDam is shown on the map, Fig. 2. This line leaves thereservoir in a short tunnel, after which it follows acontour location to a point near Daggett, where itenters a 50-mile tunnel, passing underneath the westernend of the Bullion Mountains, under a portion of theLucerne Valley, emerging from the San BernardinoMountains near the city of San Bernardino. From thispoint it follows a reasonably easy location to Pine Can-yon or other suitable reservoir.

The mean elevation of the water behind Hoover Damin Black Canyon will be 1,167 ft. For convenience indistribution, a terminal elevation of at least 800 ft.is desirable, and 1,000 ft. is preferable. If excessiveconstruction cost is to be avoided, a line as long as thatfrom Black Canyon requires a drop of approximately1,000 ft. to overcome friction losses. It is, therefore,evident that pumping would be required on a line fromHoover Dam.

If the water were brought through in a straight gravity

THE BULLS HEAD LINE

As an alternative, it is possible to shorten the BlackCanyon line by making the diversion at Bulls Head,

374 C I V I LEN GIN E E R I N G jor February I93 I VOL. I, NO.5

about 50 miles farther down the river. This plannecessitates the construction of a diversion and powerdam at Bulls Head, the cost of which tends to offsetthe reduced length of line. The pump lift is higherthan at Black Canyon, but this is partly offset by thepower produced at the diversion dam. Taken all to-gether, the estimates show this line to be slightly less

4500b.T."':!~~~.;;:f==1b!"! I I4000

~ 3 500

.s 3 000

!2500w2000l I III ID:'run'l II k._.",,:.1500~--+----t~~+----4----~----~~~---i~~1000I--+----jloj-

350 300 250 200 150 100Distance in Miles

FIG. 3. PROFILE OF TENTATIVE BLACK CANYONLINE

Showing Bulls Head Alternate

economical than the Black Canyon line. A profileof the best Bulls Head lire is also shown in Fig. 3. Thetotal lift is 2,051 ft. and the power drop at the outfallis 564 ft., as in the Black Canyon line.

THE PARKER LINE

A diversion at the Parker site, still farther down theriver, near Parker, Ariz., is likewise possible. The topog-raphy along this line permits of a lower summit ele-vation so that the total required pump lift is less thanfor the Black Canyon line, even though the diversionlevel is lower. The longest tunnel, moreover, will beonly 13 miles as compared with 50 miles on the BlackCanyon and Bulls Head routes.For its full length the Parker line is in stable and

safe location. After an initial pump lift of 539 ft. toan elevation of 989 ft., the Parker line (with dam) leavesthe river in a 12.3-mile tunnel through the WhippleMountains, of granitic formation and free from impor-tant faulting. Beyond this tunnel there is a lengthof 51 miles of surface conduit which may be of cut-and-cover conduit or open-lined canal. This sectionis located in granular detrital material, a product ofdisintegration of the native igneous rocks. It offersstable foundation for any type of lined surface channel.In its proposed location, the conduit through this regionwill be relatively free from any danger of disturbanceby cloudbursts or earth movements.The above mentioned length of surface conduit leads

to a tunnel through the Granite Mountains, whichwill be mostly in solid rock, although some detrital ma-terial will be encountered at the portals. It is not ex-pected that water will be encountered in these detritalapproaches. Leaving the Granite Mountains, the aque-duct lies largely on the surface, with a few short tunnels,in stable material, to a point west of Shaver's Summit.In this stretch are located the pumping plants requiredto lift the water up to its final summit elevation of1,817 ft.At the base of the last pumping plant, just before

reaching the summit, there exists a natural basin oflarge capacity, the Hayfield Reservoir, which can be

developed at a nominal cost and is available for theequalization of flow or as a protection against possiblebreakage in case the surface conduit leading to it isof open-canal type.West of Shaver's Summit, the line is located in a

series of tunnels along the face of the Little San Ber-nardino Mountains. The tunnels are in a stable blockof ancient rock which shows little if any importantfaulting.Emerging from the San Bernardino Mountains, the

line crosses the upper end of the Coachella Valley inconduit. The San Andreas fault and its importantbranches are traversed on the surface under condi-tions which insure reasonable safety against seriousdamage in case of movement. The line then passesunderneath the San Jacinto Mountains in tunnel, emerg-ing near the mouth of Potrero Canyon in Perris Valley,where the San Jacinto fault line is crossed at the surface.From this point the line may be led to the terminalstorage reservoirs by either of several safe and satisfac-tory routes.As shown by the map, this line could be shortened by

moving the point of diversion downstream. This isimpracticable because the river channel below Parkeris not permanently fixed and a diversion from it wouldbe precarious. At the proposed diversion, the riveris confined between rock walls. The Parker site isfavorable for the construction of a: combined diversionand power dam. The height to which the water can beraised is limited by encroachment on the city of Needles,Calif., about 58 miles up the river. A dam raising thewater 72 ft. to elevation 450 is contemplated. Fouri.-dation conditions at the site are excellent for any typeof dam, except for the great depth of overburden in theriver channel. This difficulty may be offset, in part,by deferring construction until after the river is undercontrol at Hoover Dam.The diversion may be made by pumping directly

SAN ANDREAS FAULT, NEAR SALTON SEA, FROMTHE AIR

Characterized as the Most Important Fault in California if Noton the Entire Earth

from the stream, or a combined diversion and power. dam may be constructed. The power producible atthe site will pay for the dam. If the dam is not built,it will be necessary to install clarification works at thepoint of diversion. In this event, a low-head pumpingplant will be provided to lift the muddy water into theclarifiers, and only clear water will be delivered to the

VOL. I, NO.5 C I V I LEN GIN E E R I N G jor February I93I 375

high-head plant. A profile of the Parker line, as atpresent projected, is shown in Fig. 4.

THE PICACHO LINE

The lowest practicable point of diversion from theriver is at Picacho, about 20 miles north of Yuma,Ariz. It is contemplated that the water would be di-verted by pumping directly from the river. This couldbe accomplished with safety at the selected site, as theriver is confined between definite rock walls and hasno opportunity to meander. A low diversion dam couldbe constructed, but its cost would be prohibitive. Inany event, it would be necessary to install and operatesome type of desilting equipment, as a storage reservoircapable of absorbing all prospective future silt accumu-lations is not feasible. The water would be pumpedfrom the river through a height of 332 ft. to elevation516 and delivered into a tunnel leading through thePicacho Mountains to the northern slope of the ImperialValley. This tunnel would be partly in rock, thoughtto be of stable character, but toward its western end itwould encounter an alluvial formation for a considerabledistance.After emerging from the first tunnel, this line skirts

the northern rim of the Imperial and Coachella Valleysfor a distance of more than a hundred miles, parallel toand near the San Andreas rift, as shown in Fig. 2. Thisrift is characterized by numerous side faults. Accord-ing to Dr. Buwalda, "it appears to be inviting troubletofollow the San Andreas fault closely for long distances."

ALL-AMERICAN CANAL ROUTE

It is possible to eliminate the eastern end of thePicacho route by pumping from the western end of theCoachella branch of the All-American Canal, which,as shown in Fig. 2, follows the San Andreas rift evenmore closely than the Picacho line and is consideredmore dangerous.

4000 -f---+--~ ••i--+---t---t---iJi

3500

3000

3SO 200 ISODistance in Miles

100 SO300 250

FIG. 4. PROFILE OF ADOPTED PARKER LINE

It is probable that a cooperative project would in-volve unavoidable operating difficulties, and it wouldprobably be necessary that the All-American Canal andits branches be under full control of the irrigationinterests. This would leave the Metropolitan WaterDistrict dependent for its supply upon the operationby an outside organization of a long irrigation canal.It would also be difficult to enforce necessary sanitaryregulations along the irrigation channel.Losses in an unlined canal through a sandy region

like Imperial Valley would be tremendous. So the only

way to make this project feasible, as regards losses,would be for the Metropolitan Water District to linethe entire canal at its own expense. The practicabilityof such an arrangement is questionable.

THE BRIDGE CANYON LINE

Of the lines shown in Fig. 2, the Bridge Canyon line

3000

Bridl'Co.,."•...-ii~2500

i2 000H-~Rffif+H-:-:+ri.st\---,H---I\w 1500\-+-'---1-;;,

10001-+=;:~== =+--+--+--

350

FIG. 5. PROFILE OF BRIDGE CANYONALL-GRAViTY LINE

is proposed as an all-gravity route, delivering water intoPuddingstone or other suitable terminal reservoir. Thisline requires a dam of from 600 to 900 ft. in height atthe lower Bridge Canyon dam site, which site appearssatisfactory for a dam of considerable height. Theplan, as presented, contemplates the construction ofthe diversion dam by the district, on the assumptionthat the power developed will be owned and controlledby it. But it is improbable that such an arrangementcould be perfected.According to this plan, the aqueduct leaves Bridge

Canyon in a tunnel 75 miles long under the GrandWash Cliffs. As this tunnel lies at a great depth belowthe surface, shafts would be deep and construction ofthe tunnel expensive. Some of the shafts are locatedwhere the alluvial material and detrital valley fillingsare of great depth and undoubtedly carry a considerableamount of water.Emerging from the tunnel, the line passes in conduit

to a point west of Topock, where it goes into a steel pres-sure line 4.9 miles long across the Colorado River,where the maximum head would be 1,025 ft. Westof the river, it pierces the Mojave Mountains in tunneland proceeds along a comparatively safe route, about45 per cent in surface conduit, to a point near Ludlow,where it passes into a tunnel 89.5 miles long under theBullion Mountains and beneath the water-filled LucerneValley, finally emerging at a point in the vicinity ofSan Bernardino. The outlet end. of the tunnel is at alow elevation and for several miles is in the water-bear-ing gravels along the northern slope of the Santa AnaValley. The San Andreas fault system is crossed deepunderground by this long tunnel. This line, a profileof which is shown in Fig. 5, traverses a most difficultgeological terrain.The claim that water would ultimately be delivered

practically without cost neglects the requirement forpaying taxes on district property outside of California.The dam, the reservoir, and 105miles of aqueduct wouldbe located in Arizona. The cost and the operatingexpense of this line are much greater than for any ofthe pumping routes.

376 C I V I LEN GIN E E R I N G jor February I93 I VOL. I, NO.5

ESTIMATES, NOT INCLUDING TERMINAL STORAGE, FOR ALTERNATIVE AQUEDUCT LINESBRIDGB CANYON PARKER, WITH PARKER, No DAM

ALL DIVERSION (DIRECT

GRAVITY DAM DIVERSION)

(3) (4) (4a)600 '72 0

1,705 450 3781,000 1,000 1,000

o 1,523 1,601498 406 406o 2,384 2,533

89.51 12.95 12.95225.64 92.60 93.678.69 18.38 18.86

315.90 265.36 266.912,800 1,430 1,430

. 56,575 2,860 2,860966

QUANTITY AND COST OF TERMINAL STORAGE

Investigations have shown that ample space for termi-nal storage near the outfall end of the aqueduct is avail-able. There are several promising reservoir combi-nations from which a development may be chosen.Possibly the most convenient combination would beone including'[the Los Nogales Reservoir, which lies inthe valley west of Pomona. Other promising reservoircombinations involve theruse of either the Cajalco site,south of Riverside, or what has been termed the Perrissite, near Lake View in the Perris Valley.Terminal storage, located as near as possible to the

delivery end of every long aqueduct, is a most desirablefeature. Such storage not only serves to iron out thedifference between the seasonal demands for water andthe uniform rate of delivery through the aqueduct,but also enables the aqueduct to be shut down when-ever necessary for repair or other purpose. The longerthe aqueduct the more important does terminal storagebecome, and this Colorado River system is one of thelongest aqueducts ever projected.Terminal storage, moreover, is even more important for

a system used for domestic supply purposes because ofits effect in improving the quality of the water deliveredfor use. Still further, terminal storage is a direct in-surance against the possibility of interruption along theentire aqueduct system which lies beyond the reservoirs.A terminal storage volume equal to 30 days of aque-

duct capacity would call for practically 100,000 acre-ft.,and this quantity would reasonably serve all other pur-poses during the early years of the project. Terminalstorage of 100,000 acre-ft. can be developed at a totalcost of $17,500,000, on the basis of building the neces-sary dams so that later on they may be raised to pro-vide additional storage as future developments require.

.r=: PARKER ROUTE SHOWS LOWES~ COSTS

A summary of aqueduct cost estimates along theselected lines, together with certain pertinent physicaldata, is shown in Table I. Of all the routes studied in

TABLE 1. SUMMARY OF COST

PHYSICAL DATA

Height of diversion dam, feet. " .Initial elevation, feet.Terminal elevation, feet.Total pump lift, feet ..Total power drop, feet. . . . . . . .Pumping. millions of kw-hr. required per year..Longest tunnel, miles .Total length, all tunnels, miles.Total length, all pipe lines, miles.Total length of aqueduct, miles.Deepest shaft, feet. ..Total depth of shafts, feet.Years to construct ..

BLACK CANYON

(1)BULLS HEAD

(2)

120640

1,2202,051564

3,15451.33105.9624.57254.011,84012,535

6

o1,1671,2201,662564

2,35351.33128.2412.69299.401,84011,825

6

•

detail, the Parker route is clearly the most favorable.The main reasons for this conclusion are summarizedas follows:1. While the Parker route is less expensive in initial

cost than any of the others except the Picacho and theAll-American routes, it shows a smaller operating costthan either of these because of its lower pump lift, andit will furnish water to the district at less cost per acre-ft.than any other safe and satisfactory route.2. From the viewpoint of the geology of the country,

the Parker route passes through the best terrain, in-volves less hazardous construction than any other route,and will be the safest line to operate.3. The Parker route is the only one on which it is

practicable to provide intermediate storage. The lo-cation of the Hayfield Reservoir gives to it an advantagenot enjoyed by any other route.4. It is located entirely in California and is free

from taxation or assessment in any other state. Watermay be taken directly from the Colorado' without inter-ference with the rights of any other state.5. The estimated ultimate cost of the Parker route,

$220,535,000, is believed to be within the financialcapacity of the district and is reasonable in considera-tion of the value of the service it will render.6. The advantage of slightly lower initial cost of

both the Picacho and the All-American routes is morethan outweighed by the generally unfavorable terrainon both of these and the disadvantageous operatingconditions of the All-American route.The foregoing conclusions are also those of the Engi-

neering Board of Review of the Metropolitan WaterDistrict. The Board, appointed to review the reportof the Chief Engineer and to study the problem as awhole, consisted of:' Chairman, Thaddeus Merriman,Chief Engineer of the New York City Board of WaterSupply; A. J. Wiley, Consulting Engineer of Boise,Idaho; and Richard R. Lyman, Consulting Engineerof Salt Lake City. Its report, submitted on December19, 1930, confirmed and endorsed the conclusions setforth in my report of November 14, 1930.

PICACHO

(5)

o184

1,0001,997620

3,23115.3456.7118.43234.121,4302,620

6

ALL

AMERICAN

(6)o

1771,0001,888406

2,65212.9538.1815.69271.441,4302,045

6

COST IN DOLLARS

Preliminary investigations. $2,500,000 $2,500,000 S2,500,OOO $2,500,000 $2,500,000 $2,500,000 $2,500,000Head works ... .... 500,000 13,970,900 68,163,000 13,058,400 3,983,000 3,812,200 3,219,200Aqueduet. .... ...... 194,529,000 163,051,100 370,977,000 144,423,700 145,942,100 132,836,800 117,334,800Auxiliary storage. 0 0 11,000,000 76,900 76,900 0 2,115,000First Development (800 see- It.) :Pumping plants .... ........ 13,047,000 20,867,000 0 24,733,000 26,650,000 35,680,000 29,165,000Power plants at diversion ................ 0 705,000 11,004,000 516,000 0 0 0Return power plants ...................... 2,286,000 2,306,000 0 1,100,000 1,100,000 5,027,000 2,878,000Total construction ... .................. 212,862,000 203,400,000 463,644,000 186,408000 180,252,000 179,856,000 157,212,000Total, including interest ..... 239,006,000 227,346,000 557,846,000 206,279,000 199,442,000 199,180,000 174,265,000

Future development (1,500 sec-It.) .... ...... 9,724,000 15,768,000 4,284,000 14,256,000 14,112,000 15,552,000 13,320,000Total capitalized, operation and maintenance. .. 121,617,300 135,940,000 145,918,000 119,454,000 128,635,000 152,642,400 133,146,400Capitalized return on power sold ..............• 0 0 55,095,000 0 0 0 0Average perpetual cost per acre-It .............. 23.35 23.95 39.99 21.60 21.82 23.34 20.30