303. Measuring devices, Big Laramie River Basin, 1936

TMENT OF AGRICULTURE LTURAL ENGINEERING TON, D. C. IAL BUSINESS • _IfjiN % 4.) ind-9 7.• I VII cn Mr. R.L. Par shall,

Senior Irrigation Engineer, Colorado Agr. Ekperinent _Station, Fort Collins, Colorado.

PENALTY FOR PRIVATE USE TO AVOID PAYMENT OF POSTAGE, $300.

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IMI 1110 LA2A1012 SAM 12 042.0241111104

I. L. Itarshall, Meier Irrigation Niegiawar

altrOla of Agricultural Angineorines V. Depairtment of agrieu arms. Soloredo Atgricultural Axorriased Maim

Sort Collins, Color. ..eoptcabor 14, Mg.

AS inspection of conditions along the Big Laramie, McIntyre end a number of tributaries, all la Colorado, was made es „Aiptember

5

and

6, 1936,

for the purpose of oohing suggestions mad mommesilations as to the Installation Ot proper and suitable beadiest**, at the point of diversion, for controlling the flow into ditch*s for irrigation needs and the use of a practical measuring devise to determine the veto of Mow or extent of the amount of diversion from the stroam. The request for sea an inspection and report covering mr suggeations and roommommlattone was &bested to M4 by ,. c. Filaderlidor, State anglneer of Colorado, in concurrence with John 3tats inglueor of Wyoming.

BeeeMmeedetions and suggostions conoorning the installation of a 10-foot Parshall mommailmg flume in the Skyline Mimi'.

It is reOlmmended that a 10-foot reinforced eonereto, fershall measuring flume be installed in the okyline Diteh at a point approz-Imotely 50 feet downstream free the present rating flume. A profile of this *esti= of the ditch indicates Sher* is sufficient tell to

provide for free-floe sessaroment through this new flume under the t011 memo of di...barge up to a maxima of at least 250 seeond-foet.

.2.

Ia esseetioa with the esetruction of this as flues it is seggeeted that the right hood side of the present sods rating flume be removed sad the Simnel be eidemed to a bottom width of at least 15 feet at this 1st; also that the enlargement of this seetimo of the di,* to a bottom width of 15 feet, be extended be* mpstesa sod dossatrems twos the old rating flume structure is swam to give proper awes& eonditions to the new eonerete fous-,.rieg flume* It is farther resememded that the iaside of the eurfee

right hand Usk, just below the as structure, he removed to widen the ehanael at this point am* else Is improve the laigmmeet. The neer materiel obtained from these seevisted yeeldons of the channel ihould be weed in raising the outside or left Meek about one fort between the front and of the eiow flume mod a point 200 to 250 feet upstream* The heavy stone takes twee this enlarged eeetVan of too 'hese' Mould be arremged along the neat line of the too of the

ales as a means of preventing sloughing and saving of the bank into the di tab emd thme reducing the ores section of the sbacsOL,

Is all probability it will be found neettessry to mom the entire old rating ammo strsotsm In this most the leg cribbing iimediately above and below this old time. should be takes set sod a rubble wall, be pissed so as to steed fres the upstream and et tbo soma transition mall of the new flume to the Maestros sod of the

proem* rubble wall. _{The deposit of loess materiel ss the inside} of the first var.*, upstream tram the as flume, ahead be reacved to improve *kennel seditious*

-3-It is recommended that tLe axis of the new concrete

mrasering flume be made to a4;ree with that of the improved OWN& (upstream), and that the elevatioa of the erect of the flume be CMS

as to agree with the present floor of the old rating film stimeturlo. Booms. the flow thro40 this new fltime will not be aubmorgod it Is reoommonded that no provicion be made to measure the throat or Ma gags Might.

the automatio gags height reoordimg tastrument now in uso (Bristol circular ebart typo) is said to be in good working erder• It is rosmansided, however, that this instrument be oloanod,

ressuditionod s aud regulated each nring before the water is startel throw& the ditsh, sad be operated iu manoetion with this newly Installed mussering flume. Its present Lastrumsat shelter appstra to be iu good ammiltion ard sea be used tor the same purpose on this now flume*

Liens and a memorandum concerning the building of this 10..floot conarote measuring flume burs been prepared amid submitted to

Mr. C. Bartols, President of the water lapply sae stereo Company at Fort Collins. It is my usdersteating that soastruetion or this lnirovemmat is sow wader we.

.4-Reeessesdations conosrniag iSgseommests at the *est rortal of tkie

Laremie-Pastre tunnel

Ike physleal condition* as to tbe diversion works, Mediate sentrel, sod meassrement of the Moe mere fated Is be essentially as falsest

its diVersisa s serees the Laramie River appears to be in good sesilition. The aisles gates, for regulating the river flow, are in rsir condition; however, because of lumber eonstruction, these should be reconditioned and repaired. Attention should be gives to the setter of properly by-passing, through the sluice gets, the emsd carried in the river. As for present operation, it appears theta considerable portion of this material is draws into the diversion channel and deposited some distance dovinstreem tram tie aim headgate.

Aith further study at the problem of diversion works it would some probable that a practical dimign could be developed which would

largely eliminate tke aesumuletion of send and gravel in the diversion Mussel *ad ales provide for a more sebetantial sluise way and

regeistion gates.

The min relateireedi eseelete heel gits is sliewing eotualtierable deterioraties ewe will shortly seed major repairs. At tbe time of sy inspeetion all three of the metal slide gates were partly opened. A gest bag des vas tkveas across lke themsel at a point seme 50 feet ups _{tress fres the headsets structure. Wo water was passing into tke} diversion Ousel.

.5.

The diversion cuannel, for a distemee of 300 feet or more, was badly filled with *wee river sand and fine gravel. This filling was found to be from 5 1/2 to 4 feet at various pieces ea determined by

seeeg semadiags.

At a point

ghee.

Goo

feet deemstrima from the main beadgate, in the diversion channel, is located a _{12-foot :arshall weesuriag} flume of framed %Jibsr construction, kaviag a double 1-indb boftrd floor end walls. This structure was built some years ago and was found to be in a fair state of preservatioa. _{This flume could be '} used for another year or so for the measurement of nos. It is the usual experiease that with struetures built of untreated material, the period of life, or useful service, is ratter hatted. The

instrument shelter and stilling well are in a bad state of mats.. as _{of the major difficulties concerning this problem, as a} whole, is the constricted akemael between the measuriag flume and the portal of the tunnel.

This

_{channel section is approximately}

400 filet long in a deep

out threelh mars*

gravel and large boulders. At a point about half way frau

_{the asserriag flume}

_{Is the portal of} the tinsel a measureless% of the actual width of the Channel diselosed this to be only 4 1/2 to 5 feet. _{The sides and bottom are irregular,} and the bottom, for some distaneo, is above

gre4e

*ben the true grade is assumed to be that line from the lower eud of the **assuring flume te the invert of the portal

or

the tunnel. Because of this constricted Oblimmel the flow of water through the assurarise flume is checked to Ma

en

_{extent es to produce a high degree of submergeeee.}

It is specifically reeemmemded that:

e. h more detailed *tidy be gives to the matter of diversion

works particularly to *treat improvements *at would insure against the, deposition and ascumnlation of sand and gravel in the diversion shannol. It is reasonable to sesame that sueb improvements are possible and would be advoatemesse is the operation of the diversion of water through the tenant.

b. Repairs to made on the eemerote beedeste structure, including plateaued of OM eoasraul dills in tho gate openings in order that the Wes Lay be properly seated and mode watertight. The *Actual elevntion of these sills should be determined by s carefully

prepared profile of the channel extending from the river channel to tbe invert of tho portal of the tunnel. This improvement to the heedgato structure should be iu keeping with the plan of the send trap and river sluicessys.

e. The amnia between the me-suring flume and headgeto structure be improved by removing tbo emeemmlation of said and gravel on the bottou to such a depth as will agree with the proper grade

determined by the profile previously mentions..

I. In view of the feet that the preeent It-foot Perahall measnring flume, of timber construction, has been in this chAnnel for the pest several yaws; that the instrument shelter and stiiiii411011 are in bad re;:eir; the, Ihe ramining *seta life of this

is limited; that the redetermined grade line will probebly she, that the flame would operate effisiontly it placed on a lower

-7.

any diastase that the measuring flume could be relocated

advantageously, it is therefore concluded that in view of these severel possibilities of improvesmit that this old wooden Mae structure should be reneged end a eatable reinforeed concrete Parsball measuring flume be befit, of ample dimensions and

properly located. This new structure should be provided t th both

Ka

and ha stilling wells, and an automatie double-head

gsge height recording instrument should be installed and operated In conneetion with it.

e. That the channel between the present measuring flume and the portal of the tunnel be improved according to the following apprtaimate dimensions and alignment: The interseetion of the side slopes with the bottom of this seetion of the diversion channel should be according to the diverging limes extending from the sides of the portal of the tunnel, a width of about

6

feet, to a width of about 15 feet in a distance of some 400 feet, and in plan symmetries' with the axis of the channel er 'enter point

or

the present measuring flume. the bottom of this ohesnel 'Mild be brought to the pro);er graft, and the banks Mould be

laid up with rubble walls to prevent aleughing sad the cavic47 of lsese material from the side slopes, and thus eliminate the reeurrenee of present conditions.

4-Ueadowlemd ditehes along the Laremde River and tributaries in Colorado.

There are approximately sixty diversions from the tare:ado, eintyre, Deadnaa, „Aubb, stook, and other streams in this drainage arse. Tor the most part these ditches are smell, carrying a flow of less than 15 seeond-feet of water. They are relatively short, UMW in gravelly soil, and almost without exception ere void of headgetes for regulation and kiwi no practioal means of measuring the rate of flow or extent of diversion. The diversion dams are of ▪ teaporary nature end consist generally of loose roek barriers thrown across the stream.

It was noted for zany of the meadows served by these ditches 'het the slope of the ground surface or topography, was mash as to

promote good drainage book to the streams. Seamus* of the *lose proximity of the meadows to the stream Ohemaelso twarsitY• sad porous gravelly subsoil, it is estimated that et least 7, percent of lbe beeigate diversions are returned to tr.* stream. The eonsamptive use of water on these mountain meadow 18nde will be at least one aers-foot per acre per season. The actual use of water on theme meadow lands, in acre-feet pf*I- acre, is net definitely knoen, but it is quite probable that the total annual headgate diversion is in

mess of

5

aire-foet per sere per year. The species or type* and kinds of vase.. eonstituting these meadow crops require adequate water for proper growth eel sufficient soil moisture should be

maintained at all times. Seems* Of the wor /Motors involved in the proper irrigation of these Land* (Mnik as tegMeraphy, soil, altitude,

=pears, end method of api,liestion of water) it is unseasonable to assume that enfflelest eater will be provided ehes the Mr of diversion, at the bead gale, Is taken to be ene sere•teot per etre.

The proper administration of the waters ot the Kg Lerma* and its several tributaries involves compliestions of various digress of seriousness, sspecielly eh re priorities from different streams cosetitute the irrigetlea supply for one meadow. This

eonclusion is based is the tett that eareful measurement of diversions will be eeseeeerr properly to administer the priorities in safeguarding the rights ef the Oppepristers. Is mv recent inspection of several of these meedowland ditehes, attention was diraetad to the Davy Oita', diverting fro- Dead ilea Creek, a tributary to the Sig Laramie through Nunn Creek. A, a point about in. mile below the point of diversion, Don CreeK enters the ditch from the east. The extent of this added supply is not known but probably it is less than 200 sere-feet per season. ho AMA/ of measuring the flow of Pot Creek was apparent. however, 100.11.8 can be provided readily. _{At the} lower sad of the Davy Litch, near Brous Creek, is the Forrester lit& shiek diverts free this wreak. As I understand the relationship here, the Forrester Tata 'outlaws dews the Laramie River Valley to serve the lower portion of the Louis Shaine meadow, with as arrange-nest effective by whit* the tail water from the Davy Ditch *an he added to the ?arrester Ditch water. At present the delta sem* famed at the mouth of Brown Creek 'Canyon allows the stream Is As. in at least three different end distinct channels. One of these chsacels

way serves as the aver stretch of the Forrester AIch. ,t times whea this spook is discharging several seeond-feet it apiAkared that all three branches would be running water. The *mom above that diverted by the Forrester Ditch is interaepted by the Davy Ditek Whisk skirts across the lower edge of this delta cone. it was determined by inspection that Bross Creak could be so improved as to cause the total flow to be diverted iate the Forrester Ditek as a single stream and measarewest at its discharge eould thus be

obtained. This flew ay at tiers =Oh exceed the ditch appropriation of

7

secoad..teet4

Its wads* served by the Davy sad Forrester ditches is also covered by We giber ditches, namely the groan Lite% out of Nunn Creek and the Parker Diteb out of the Big Lavoie River. A suggestion for

the praetleal handling of this situation is that the Davy and Forrester ditches be permitted to intercept the total flow of both Don and Bross sreeke and the diversions be regulated thremgh the Brows sad Parker ditches accordingly. This one case in the adataistratiem of eater is merely cited to aall attention to the problem of iroper regulation and measuring of the appropriations of water for this one large meadow.

Time did not permit the investigation of all the ditches sad their respective problems.

Te meet requirements as to regulation sad inemenremat of diversion from the BigLessmie and tributaries, the filleeing recommendations are madot

-11-That all ditches be provided with substantial headsets* ef preetical design. Iu mg inspection of nearly 50 peremat et these meadowland ditches, I found that not one as adequate': **sipped for mistral sad regulation. The Link A-- Ditch has a substantial dem Chore the diversion to the diteh is through a box culvert at the end of dea. This opening is without a slide gate, flash boards Wog used for regulatioa. It is reeemmemied that same type of sores er lever lift be provided for ndequately adjusting the flow, these headgate structures to be built aceording to some acceptable and apiroved plea or deals*. _{its a means of keeping the expense below what would be} involved by concrete, a practical design using log crib and rock fill construction should be employed. _{The structure should be}

provided with one or more slide gate, as required, these to be water tight and made of 2-ineh lumber equii,ped with a preetieal lifting devise. _{titmouse of the soarse gravelly foundation, it} will be mammary to provide ample eatPott eella to ;revsnt a flow beneath or around fhe structure. its wing wall protection should be provided, espeeially on the upstream,. tailgate end. b. _{That trash ditch diverting from a stress be previded with a}

Parehall measuring flume of suitable else and espeeity. It Is reSemstanded that these flumes be of framed, lumber Samslarsetlas, 2.4s4M pleak being used for walls and floor with 4 by 4 in* sills sod pests and double 2 by

6

indi areas ties. This material should

-12•

be native lumber, surfaced four sides to

salters ilaeseiese

and ereosoted before fabrication. Galvanised eatted nails and belts should be used to insure a loft life for the structure. The building it thee. flumes should be ender the supervision of an experienced earpsater in order that they Shall be built property accordinc to specified dimeasleas and be aalfira is eonstrustion. _{The flame mwy be eeesabled in two parts in tie} shop, namely the seavergiag wnotlea, as one plea', and the throat and diverging sections ea the Oh. Ihs esaplete structure COY:

then be

put together at the site

or

_{loestion and She ups. and doma.}

strong wings instals. after the flume proper is careftelly aligned sod leveled in plea'. _{It is important that some engineer}

ft/411ar with this type of ceaeuring devise be

assigned

to the

Installation

of these

60

_{or mese flumes. 4 inspection revealed}

that for the greater number of eases no problem would be involved as to the 4102,00 setting of the flies. There will be required, no doubt, in an °sessional instance, beams of the relatively flat grade

or

_{ditch, a short profile of the 460111114 to guide in}

setting the crest of flame et the most desirable elevation. IS may leiter be found necessary to raise the crest of She diversion dam slightly in order that the flow through the flame shall net b.

tee kidity sebusesed.

_{Where submerged floe conditions out not}

be avoided without tremble and =se, _{it i* recow.anded that}

beak le 41.4 Nib SW

_{or stilling soils be provided. Afore the}

.0.

enamel gage staff, graduated la feet, tenthe asd hundredths, be fixed vertleolly at the proper point es the iselde fees of the converging section. _{#or submerged floe, s point gage is to be} used is determising the Ha and hb heeds which, when referred

to a diegrms sad table, will give the rate of discharge is eeeesd-feet* _{It Is sot reeemnended that autosetie water-attge recordisi} isstrumeste be used in SOSSOOtitni with Ws _{group installation of} the karshall sessuring flume*

The matter of location of the flume with reference to the

listened, from the head gate should be given eassideration. _tould this lesation be within 50 or 100 feet of the gate, the water

official would find it most convent's% for sagpliaties, lames if it is at a seasiderable distance does the MA& =eh ties will be required in properly adjusting the rate of disebarge* goseese

or

seepage losses in th, se small ditebes, it would be equitable to the user to maim?* the rate of diversion At a reasonable distance from the needgate• _{in some eases, as ea* observed, the meet} favorable lesation for operatins the flume will be found at seise di _{stases downstream from the point of diversion.}

Time did sot permit me to inspect the Deed Man labia into Mod Crest, a diversion into the north AmAdre drainage* is netter will to given attention at an early date and a brief report submitied covering it.

October 19, 1936

William R. Kelly, Esq. Attorney at Law

Greeley, Colorado

Re: Measuring Device on Laramie-Pore Tunnel

Dear Mr. Kelly:

Some weeks ago I addressed a letter to Mr. Clark Moore, advising that it was possible we Nould nave to require the installation of a new Parshall type measuring flume near the west portal of the Laramie-Poudre Tunnel, together with other improvements in connection therewith, in conformity with the views of Mr. R. L. Parshall. We have recently receiveu Mr. Persia:ill's report and recommenda-tions covering the need for measuring devices, and the type of same, in the Laramie River lialley in Colorado, in which I fully concur, and in which State Engineer Quinn of Wyoming also concurs, with one slight exception,

ing to tae type of recorder on the Skyline Ditch. With respect to the Laramie-Poudre Tunnel, following improvements:

The physical conditions as to the diversion works, headgate con-trol, and measurement of the flow were found to be essentially as follows:

The diversion dam across tae Laramie River appears to be in good condition. The sluice gates, for regulating the river flow, are in fair condition; however, because of lumber construction, these should

be reconditioned and repaired. Attention should be given to the mat-ter of properly by-passing, thru the sluice gate, the sand carried in

viz.,

William R. Kelly -- 2 10-19-36

the river. As for present operation, it appears that a consider-able portion of this material is drawn into the diversion channel and deposited some distance downstream from the main headgate. With further study of the problem of diversion works, it would seem probable that a practical design could be developed which would largely eliminate the accumulation of sand and gravel in the diver-sion channel and also provide for a more substantial sluice way and regulation gates.

The main reinforced concrete headgate is showing considerable deterioration and will shortly need major repairs. At the time of sly inspection, all three of the metal slide gates were partly opened.

A land bag dam was thrown across the channel at a point some 50 feet upstream from the needgate structure. No water was passing into the diversion channel.

The diversion channel, for a distance of 300 feet or more was badly filled with coarse river sand and fine gravel. This filling was found to be from 3 1/2 to 4 feet at various places, as deter-mined by actual soundings.

At a point about 600 feet downstream from the main headgate, in the diversion channel, is located a 12-foot Parshall measuring flume of framed timber construction, having a double 1-inch board floor and walls. This structure was built some years ago and was found to be in a fair state of preservation. This flume could be used for another year or so for the measurement of flow. It is the usual experience that, with structures built of untreated material, the period of life,

5il1iam R. Kelly -- 3 _10-19-56

or useful service, is rather limited. The instrument shelter and stilling well are in a bad state of repair.

One of the major difficulties concerning this problem, as a whole, is the constricted channel between the measuring flume and the portal of the tunnel. This channel section is approximately 400 feet long in a deep cut thru coarse gravel and large boulders.

At a point about half way from re measuring flume to the portal of the tunnel a measurement of tele actual widtn of the channel dis-closed this to be only 4 1/2 to 5 feet. The sides and bottom are irregulart, and the bottom, for 5=0 _{distance, is above grade when}

the true grade is aesumed to be that line from the lower end of the measuring flume to the invert of the portal of the tunnel. isecaune of this conntrioted channel, the flow of water thru the measuring flume is checked to such an extant az to produce a high degree of subetergence.

It is specifically recommended that:

a. _{A more detailed study be given to the matter of diversion works,} particularly to effect improvements that would insure against

the deposition and accumulation of sand and gravel in the diversion channel. It is reasonable to assume that such improvements are possible, and would be advantageous in the operation of the diver-sion of water thru the tunnel.

b. _{hepairs be made on the concrete headgate structure, including} place-ment of new concrete sills in the gate openings in order that the gates may be properly seated and made watertight. Thu actual

ele-William R. Kelly -- 4 10-19-56

vation of these sills should be determined by a carefully pre-pared profile of the channel extending from the river channel to the invert of the portal of the tunnel. This improvement to the headgate structure should be in keeping with the plan of the sand trap and river aluiceways.

c. _{The channel between the measuring flume and headgato structure} be improved by removing the accumulation of sand and gravel on the bottom to such a depth as will agree with the proper grade determined by the profile previously mentioned.

d. In view of the fact that the present 12-foot Parehall measuring flume, of timber construction, has been in this channel for the

past several years; that the instrument shelter and stilling well are in bad repair; that the remaining useful life of this flume is limited; that the re-determined grade line will

pro-bably Show that the flume would operate efficiently if placed on a lower elevation and that further study with the aid of a fixed grade line may disclose that the measuring flume could be relo-cated advantageously, it is therefore concluded that, in vievi of these several possibilities of improvement, this old wooden flume structure should be removed, and a suitable reinforced concrete Parahall measuring flume be built, of ample dimensions and pro-perly located. This new structure should be provided with both Au and Hb stilling wells, and an automatic double-head gage tight recording instrument should be installed and operated in connec-tion with it.

William R. Kelly -- 5 10-19-36

e. That the channel between the present measuring flume and the portal of the tunnel be improved according to the following approximate dimensions and alignment: The intersection of the side slopes with the bottom of this section of the diversion channel should be according to the diverging lines extending from the sides of the portal of the tunnel, a width of about feet, to a width of about 15 feet in a distance of some 400 fee, and in plan symeletrical with th axis of the channel or

center point of the present measuring flume. The bottow of this channel should be brought to the proper grade, and the banks should be laid up with ruble walls to prevent sloughing and the cavin of loose materiel frou the side slopes, and thus eliminate the recurrence of present conditions."

This office is prepared to furnish tne necessary elevations and profiles called for in Mr. Parshallis recommendations. The construction of the flume in question requires not only mechanical skill, but also ample experience in such work, in order that mistakes, resulting in expensive changes, may be avoided. The Water Supply and Storage Company has just completed two large reinforced concrete flumes, under the direct supervision of Put Costigan, their ditch superintendent. I have not seen these flumes, but aa advised by Mr. Parshall that they are com-pleted with great accuracy, and constructed in a very acceptable manner. It is suggested that it may be possible for your company to employ r. Costigan to do this particular piece of work, to its advantage. I have just been advised by

William R. Kelly -- 6 _10-19-56

Mr. Temple that their concrete machinery is still on the ground, and it might be that tae same would be available for the use of your company.

In view of the provisions of the last decision of the Supreme Court, which provide that the methods of measuring the waters diverted by Colorado ditches shall he determined by the two State Engineers in question, and since this decision has been made by an authority to which the matter was referred by the State Engi-neers, we feel it necessary to require that the Laramie-Poudre Irrigation Company proceed without delay to the carrying out of the program recommended by Mr. Par-shall, tc the end that your compnny may not be deprived of any water next spring thru having failed in such compliance.

Prior to any actual work being initiated, we deeire that this office be advised, so that we may furnish the necessary lines and grades and locutions upon which the flume will be constructed.

Very truly yours,

Memorandum Relative to Improvements of Parshall Measuring Flume, Cameron Pass Ditch, ',,ater Supply and Storage Company,

Fort Collins, Colorado.

A brief inspection of conditions of the Cameron Pass Ditch and the present 2-foot timber Parshall measuring flume was made on October 4, 1936.

The proble- of lowering or depressing the grade of this small channel was given consideration. Tecause of the nature of the outlet conditions just upstream from the flume, there appears to be no limitation to the lowering of this structures about one foot. It would be permissible to exceed this

amount if it is thought advisable, however, it is suggested that whatever lowering of the measuring flume is made that tlie invert of the culvert p under the hihway about 250 feet or more upstream, be made to agree with the .;rade of the chnnel. It is estimated that this actual difference should show the flume elevation to be about 0.3 or 0.4 foot lower than the invert of the culvert.

Because of the inflow into the ditch between the flume and the culvert, it is suggested that the new flume be of the sEme throat width as the present structura and located at the srme place ir the channel. The present wooden flume appears to be in a fair state of 1)reservation and could be dismantled and rebuilt at the lowered elevation. If this is done, it is suggested that 45-degree wing walls be provided at the upstream end of the flume as recommended for the standard setting. Because of the permanency in building it

is believed that the better plan would be to construct this new flume of reinforced concrete as outlined in the

Einclosed Experiment LAation Bulletin 423, "The Pnrshall Neasurin, Flume".

R. L. Parshall,