UNITED STATES DEPARTMENT OF THE INTERIOR

BUREAU OF RECLAMATION

u Rhone

HYDRAULIC MODEL STUDIES OF THE OUTLET WORKS KEYHOLE DAM--BELLE FOURCHE UNIT, WYOMING

MISSOURI RIVER BASIN PROJECT

Hydraulic Laboratory Report No. Hyd-338

ENGINEERING LABORATORIES BRANCH

DESIGN AND CONSTRUCTION DIVISION DENV E R, COLORADO

September 15, 1952

FOREWORD

Hydraulic model studies of the outlet works for Keyhole Dam. Belle Fourche Unit. Wyoming, Mis­souri River Basin Project, were conducted in the Hydraulic Laboratory of the Bureau of Reclamation at Denver. Colorado, during the period June 1949 to July 1950.

The final plans. evolved from this study, were developed through the cooperation of the staffs of the Spillway and Outlets Section No. 2. the Mechanical Section, and the Hydraulic Laboratory.

During the course of the model studies. Messrs. H. W. Tabor and R. H. Whinnerah of Spillway ~d Outlets Section No. 2 frequently visited the laboratory to observe the model studies and to discuss test re­sults.

These studies were conducted by W. E. Wagner and R. H. Slykhouse under the supervision of Messrs. A. J. Peterka and J. N. Bradley of the Hydraulic Laboratory staff.

Summary •••. Introduction . . . • . The Models •

CONTENTS

. . . . . . . .

. . . . . . . . . . . . . . . . . . . . .

The 1: 20 Model The 1: 9. 75 Model

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

The Investigation. . . . . . . . . . . . . . . . . . . . . Slide Gate Studies

The 1: 20 model • . • The 1:9. 75 model . .

. . . . . . . . . . . . . . . . . .

Tunnel Studies- -1: 20 Model • • . . . . . . . . . . . Preliminary wall Wall No. 2 ••.• Wall No. 3 ••• Wall No. 4 •••

Stilling Basin Studies •

. . . . . . . . . . . . . . . . . .

. . . . .

. -. .

. . . . . . . . . . . . . . . . . .

Page

1 2 2

2 3

4

4

4 5

5

5 6 6 6

6

Preliminary d~sign • • . . • • • • • • • • • • • • 6 Revision No. 1 • . • • • • • • • • • • • • • • • • 6 Revision No. 2 • • • • • • • • • • • • • • • • • • 6 Revision No. 3 . . . . . . . . . . . . . . . . . . 7 Revision No. 4 • • • • • • • • • • • • • 7 Revision No. 5 ~ • • • • • • • • • • • • • • • • • 7

The Recommended Design • Head Loss in Gate Chamber Method of Prototype Operation

. . . ~ . . . . . . . . . . . . . . . . . . . . . . .

Location map . • . . . . . . . . . . • . . . . . . . . General drawing of dam. • . • • • • • • • • • • • • • General drawing of outlet works • • • • • • • • • • • • • The 1: 20 model . . • • . . . . • . . • . . • . • . . • . . Tail-water curve • • • • • • • . • • • • • • • • The 1: 9. 7 5 model . . • . . . . . . . • . . . • . • . . Flow of 750 and 1, 500 second-feet--preliminary design • • •• Maximum flow through downstream gate frame • • • • • • • • Various splitter walls tested • • • • • • • . • • • • Revisions to improve flow distribution in stilling basin •• Stilling basin operation using Caballo hump • • • • • • • • . •

7 8 9

Figure

1 2 3 4 5 6 7 8 9

10 11

CONTENTS- -Continued

Figure

Both gates discharging 1,500 second-feet--recommended design • 12 General details of the recommended design . . . . . . . . . 13 Both gates discharging 900 second-feet-.:.recommended design 14 Right gate discharging 450 second-feet--recommended design 15 Right gate discharging 750 second-feet--recommended design 16 Right gate 75-percent open discharging 560 second-feet--

recommended design • . • • • • • . • • . • . • • • . . • • 17 Right gate 50-percent open discharging 375 second-feet-­

recommended design . • • • • • • • • . • • • • • . • Right gate 25-percent open discharging 190 second-feet--

18

recommended design • . . . . • • • • • . • • . . . . • • • 19 Water-surface profiles--recommended basin . • • . 20 Depth of scour- -recommended basin . . . • • . 21 Pressures in bellmouth entrance to gate chamber • • • • • • • • 22 Pressures along center ridge . • • • • 23 Pressures along trajectory curve • • • 24 Head loss in gate chamber . . • 25 Details of recommended basin. • • • • • . 26

ii

UNITED STATES DEPARTMENT OF THE INTERIOR

BURE.AlJ OF .RECLAM.A]'ION ·

Design and Construction Division . Engineering Laboratories Branch Denver. Colorado · · September 15. 1952

Laboratory Report No. Hyd-338 Hydraulic Laboratory Section Compiled by: W. E. 'Wagner Reviewed by: A. J. Peterka

Subject: Hydraulic model studies of the outlet works--Keyhole Dam-- . Belle Fourche Unit. Wyoming--Missouri River Basin Project

SUMMARY

The . .-hydraulic model studies discussed in this report were made to determine certain flow characteristics of the regulating gate. to study the flow distribution in the tunnel downstream from the gate chamber. andto check the performance of the stilling basin. The results and conclusiocontained here~ are based on tes"ts conducted· on a 1: 20 scale model of theKeyhole Dam outlet works. Figure 4. and a 1:9. 75 scale model of the slidgate. Figure 6. ·

As a result of these studies,_ the splitter. wall immediately_ down­stream from the gate chamber was redesigned and a ridge along the tunneinvert was developed to smooth the flow before it entered the stilling basi

Four different splitter walls. Figure 9, were tested. In general,the recommended wall consisted of lengthening the preliminary wall by 18feet to provide more uniform flow in the tunnel downstream from the gate chamber, Figure 9c. To aid in distributing the flow more uniformly overthe tunnel width, a ridge 7. 5 inches high was· installed on the tunnel in­vert, Figure 10d.

Studies of the stilling basin operation revealed that the basin prowas·adequate and would perform satisfactorily when the flow was evenly dtributed before it entered the stilling pool. Relatively uniform flow at thestilling basin ·entrance was obtained by installing the ridge described abovand lengthening the horizontal section between the end of the tunnel and thorigin of the trajectory curve. Revision No. 5, Figure 10d.

The performance of the recommended basin was satisfactory at aflows. Figures 14 to 19, inclusive. show the operation of the recommenddesign at different gate openings and for normal and maximum reservoir

· elevations. · · ·

Water-surface profiles in the stilling basin and scour tests of therecommended design are shown· in Figures 20 ~d 21, respectively.

Pressures were obtained in the bell.mouth entrance to the gate chamber, along the trajectory curve in the stilling basin, and at two points along the ridge in the tuI1JJ.el. Results of these tests, shown in Figures 22 to 24, inclusive; show that the pressures were satisfactory.

The 1: 9. 7 5 model of the slide gate was used to study the flow conditions within the downstream gate frame. Tests on this model indi­cated that subatmospheric pressures could be expected in the roof of the downstream gate frame if the gate were operated at openings above 98 percent. These studies are discussed on page 5.

INTRODUCTION

Keyhole Dam is a part of the Cheyenne Division, South Dakota­Wyo.tning, Missouri River ·Basin Project, and is located on the Belle Fourche River about 16 miles northeast of Moorcroft, Wyoming. Figure 1. The dam is an earth-fill structure approximately 3, 420 feet long and has a maximum height of about 165 feet above the lowest foundation.

The spillway, which is a concrete open channel with an uncon­trolled crest 19 feet 3 inches in length, is designed for a maximum dis­charge of 10, 800 second-feet and is located on the right abutment of the dam, Figure 2. The outlet works is located near the left dam abutment and is designed for a maximum discharge of 900 second-feet at reservoir elevation 4070 and 1, 500 second-feet at maximum reservoir elevation 4128. l.

The outlet works consists of a trashrack structure and entrance transition, a concrete-lined tunnel 9 feet 6 inches wide and 8 feet 3 inches high with a semlcircular arch roof, a gate chamber, and a stilling basin. Flow through the outlet works is controlled by two high-pressure slide gates, 3 feet 6 inches square, located in the gate chamber near the center of the dam, Figure 2.

The hydraulic model tests discussed in this report were made to study the flow conditions in the tunnel downstream from the slide gates and the stilling basin performance.

THE MODELS

The 1: 20 Model

The model of the outlet works was built to a geometrical scale of 1: 20 and consisted of a head box used to represent the reservoir. a section of tunnel leading to the gate chamber, two slide gates 1. 95 inches square, a transparent tunnel 12. 4 feet in length, the stilling basin, and a section of the channel downstream from the basin, Figure 4. The outlet tunnel between the reservoir and the gate chamber was not modeled since this portion of the tunnel flows under pressure and no hydraulic problems are anticipated up~ stream from the gate chamber. The tunnel upstream from the gate chamber

2

was represented by a 4-foot length of pipe formed from sheet metal and equipped with a 4-vane flow straightener at the upstream end.

The slide gates, gate chamber, and tunnel downstream. from the gate chamber were constructed of transparent plastic to permit observa­tion of the flow conditions in- the tunnel portion of the outlet works. Flow through the model was controlled by raising or lowering the gates by means .of a threaded gate stem machined from brass rod, Figure 7a.

The head box, stilling basin, and downstream channel were con­structed of wood and lined with galvanized sheet metal. The trajectory curve and basin floor- were made of smooth concrete formed to metal tem­plates and the downstream channel was formed with pea gravel approxi­mately 8 inches deep. A plate glass panel was used as one basin training wall to permit observation of the stilling action in the basin:. Piezometers were installed along the trajectory curve on the center line of the basin, Figure 24.

Water to the model was supplied by one of the portable laboratory pumps and metered through a combination venturi and orifice meter. Tail.­water elevations in the stilling basin were controlled by a tailgate located at the downstream end of the model and were set according to the tail-water curve, Figure 5.

Since friction losses are relatively higher in the model than in the prototype, computations were made, ·ll:sing_ Manning's formula, to determine the length of tunnel required downstream from the gate chamber to give · velocities in the model comparable- to those in the prototype. As a result of these computations the model tunnel was shortened 28 percent to give velocities at the origin of the trajectory curve corresponding to the computed velocities in the prototype.

The 1: 20 model was used to study the flow conditions in the tunnel and the performance of the stilling basin.

The 1:9. 75 Model

The 1:9. 75 model was built to study the flow characteristics in the downstream gate frame.· Therefore, only the gate and downstream. gate frame were made geometrically similar to the prototype. The model was composed of a 20-foot length of 6-inch conduit terminating in a short transi­tion section to which the 4- by 4-inch slide gate was fastened. Figure 6. A flow straightener was placed in the upstream end of the conduit to provide uniform flow into the slide gate. The slide gate, previously built for other model studies, was modified to conform to the design proposed for Keyhole outlet works. The roof of the downstream gate frame was fitted with piezom­eters and constructed of transparent plastic to permit observation of the flow as the jet left the gate leaf.

3

THE INVESTIGATION

The investigation was concerned primarily with the distribution of flow in the tunnel and the performance of the stilling basin when one or both slide gates were discharging 750 and 1, 500 second-feet, respec­tively, at maximum reservoir elevation 4128. 1. These flows created the most severe conditions both in the tunnel and the stilling basin. Studies were also made at discharges of 450 second-feet with one gate open and 900 second-feet with both gates open at normal reservoir eleva­tion 4070. In addition, t"'e r~cLmmended design was studied with the _ slide gates partially closed. Thus, a wide range of discharge and oper­ating conditions were studied to make certain the outlet works functioned as intended.

In the preliminary design. the slide gates were 3 feet 3 inches square and the tunnel was 8 feet 9 inches wide and 7 feet 7-1/2 inches high. After the 1: 20 model was built, the slide gate design was modified by adding small deflectors upstream from the gate slots. This modifica­tion was the result of model studies made on the high-pressure slide gate for Cedar Bluff outlet works.* The installation of gate slot deflectors re­duced the coefficient of discharge from 0. 95 to o. 84. thus necessitating larger gates to discharge the design flow. Therefore, the size of the slide gates was increased to 3 feet 6 inches square and the tunnel dimensions were changed to 9 feet 6 inches wide and 8 feet 3 inches high. The model gates and tunnel were not changed to conform to these new dimensions, be­cause the studies were essentially completed and it was felt that the rela­tively small change in size would have little effect on the flow characteristics in the model or in the prototype.

Slide Gate Studies

The 1: 20 model. The preliminary design. Figures 3 and 4, was initially tested using a aischarge of 1, 50d' second-feet at maximum reser­voir elevation 4128. 1 with both slide gates fully open. Under these condi­tions a high fin of water which extended to the crown of the tunnel was fo~med in the center of the tunnel below the gate chamber where the two jets came together, Figure 7 a. When the gates were less than 9 5 percent open. the . fin_ was reduced substantially. It was ~ound that for gate positions of approxi­mately 95- to l0O~percent open, the jet adhered to the sloping top of the downstream gate frames and the high fin, described above. became 1nore prominent.

Of primary concern, however. was the fact that the downstream gate frame acted as a draft tube within the above range of discharges and a high coefficient of discharge was noted, indicating the presence of subatmospheric pressures.

*Hydraulic Laboratory Report No. Hyd-245, "Hydraulic Model Studies of Cedar Bluff Outlet Works."

4

Since the 1:20 model of the·outlet,works-w.as-'compa.J:'atively small for a reliable study of the flow-characteristics in tbe·gate,·:a"la.rg~r'model of the slide gate was constructed on- a scale of ,l:;9. 75. : · .

. · The 1: 9. 7 5 model. Tests on this model disclosed: lil- flo·w pattern similar to that obtained on the s-maller 1: 20 model, but within a different range of gate openings. When the slide gate was exactly 100-percent- open;,

. the upper nappe of the jet was clear of the downstream frame and apparently fully aerated back to the gate leaf, Figure·Ba. Howeve:r, when the gate leaf was raised to a position 100. 6-percent open, the. jet clung to the roof of the downstream frame as in the 1: 20 model,· Figure 8b. The flow pattern per­sisted throughout the entire range of heads on the gate. When the gate was 100-. 6-percent open and at maximum head, the piezometers in the roof of the downstream frame indicated. a maximum subatmospheric pressure ·of minus 5. 2 feet of water at a point 5. 5 inches downstream from the gate leaf. The pressure increased to atmospheric from this point downstream to the en;d of the frame. ·

When the gate was raised further to a position approximately 101-percent open, the jet a:gain flowed clear and no subatmospheric pressures were noted,· Figure· 8c. Al though the lowest pressure rioted in the· gate frame is above the cavitation range, it can be assumed that still lower pres­sures may have existed between the gate leaf and the point of lowest ob-. served pressure. This assumption is based on the fact that the pressures progressively increased to atmospheric at the downstream end of the gate frame. · ·

, .

From these tests it is conciuded that the flow in the gate structure, described above, will be satisfactory if the gate is operated les.s than 98-percent open.

Tunnel Studies- -1: 20 Model

- Preliminary wall. As stated above under Slide Gate Studies- -1: 20 Model, a high fin of water formed in.the center of the tunnel below the. gate chamber. Although this fin was reduced materially when the gates were lowered to 95-percent open, there still remained a small fin of water and some splash at the end of the splitter wall immediately downstream from the gate chamber where the jets came together.

When one gate was closed, the center fin was eliminated, but on leaving the end of the splitter wall the jet spread to the opposite side of·the tunnel,. causing the flow to swing to alternate sfdes of the t:winel as it passed downstream, Figure 7c. ·.This unsymmetrical flow continued into,the still­ing basin where. an uneven jump. formed, Figure 7d.

. These flow conditions also persisted at low~r ;eservoh- ~levations but their prominence diminished.as the head water was lowered. Although the ~isturbance at ·the end of the .splitter wall had little. ;ef~ect on the stilling basm action, steps were taken to reduce the tendency of the jet to swing when one gate was closed.

l '.' ••

i ', , r ·(_ ·.

5

Wall No. 2. The splitter wall between the gates was lengthened to 22 feet 9 inches., tapered from 2 feet 3 inches wide at the gate to 8 :ill.ches at the downstream end., and sloped from 3 feet 8 :ill.ches in height at the gate to 8 :ill.ches high., Figure 9b. This arrangement almost eliminated the cen­ter f:ill. when both gates were operating. However., when one gate was closed., the jet crossed over the slop:ill.g top of the splitter wall and caused more · disturbance :ill the tunnel than :ill the preliminary design.

Wall No. 3. Next., a splitter wall similar to the one described above but with a level top., Figure 9c., was tested. This wall gave a much better. distribution of fiow with_ only one gate open. The tendency for the jet to swing from side to side of the tunnel was still present but .much less pronounced. When both gates were open., a small fin still formed at the end of the splitter wall but the splash was reduced.

Wall No. 4. To determine whether-a shorter wall would be satis­factory., a splitter wall 14 feet long was :installed in the model., Figure 9d. The shorter wall made the center fin more pronounced when two gates were operating and., with one gate closed., the flow appeared less symmetrica;L in the tunnel. It was decided to use the 22-foot 9-inch wall., Wall No. 3., shown in Figure 9c and develop other means to improve the unsymmetrical flow in the tunnel when one gate was closed.

Stilling Basin Studies

Preliminary desiw. As shown in Figure 7d and described under Tunnel Studies--1:20 Mode on page 5., the unsymmetrical flow persisted throughout the length of the tunnel and caused a flow concentration on one side of the stilling basin. When both gates were open, the flow concentrated :in the center of the stilling basin. Although the longer splitter wall helped to distribute the flow more evenly as it entered the stilling basin., it was

. felt the .flow distribution could be further improved.

Revision No. 1. A hump., 2 feet 6 inches :in height., was placed on the tunnel invert near the downstream. end of the tunnel., Figure 10a. This change was ineffective :in improving the flow distribution. The fiow still concentrated :in the center of the basin when both gates were operating and., when one gate was closed., most of the flow shifted to one side.·

Revision No, 2, The previous revision :indicated a still larger hump might distribute the flow more evenly as it entered the stilling basin. A hump of dimensions and shape similar to that in use at Caballo Dam outlet works** was installed :in the model., Figures 10b and llb. In general., the flow conditions were worse with the-Caballo hump :installed. In addition to the unsymmetrical flow., the jet failed to penetrate the stilling pool and skipped along the pool surface., Figure llc.

From these tests., it became apparent that the unsymmetrical flow should be corrected :in the tunnel rather than at the stilling basin entrance.

**Hydraulic Laboratory Report No. Hyd-72., "Hydraulic Model Studies for the Design of Caballo Dam Outlet Works and Spillway."

6

Revision No. 3: ne:vision'N0~ 3' cbrtiisted of placing a ridge, triangular in cross section and'20 ,mc'hes in height along the center line, on the invert of the· tunnelfrditi Station 10+5lto fhe··tunnel ·portal., Fig­ure 10c. It was hoped the ridge ·would'serve to partially divide the flow and force more ~o the ou~side edge_s of the stilling basin.. .

The ridge' helped materially in forcing more flow to the outside of the stilling pool when both gates were operating. With one gate closed, the flow distribution in the'. stilling basin could be made satisfactory at a

· given head and discharge. ·However,· when the head or discharge was in­creased or lowered, the frequency of the jet swing from the tunnel sides was changed and the hydraulic jump in the stilling basin again became un-symmetrical.. · · ·

In an attempt to make the flow uniform at all heads and discharges, the 40-foot length of ridge was moved to a position immediately downstream from the gate chambe.r. This arrangement gave fair flow conditions over a wider range of discharges,· but in the near maximum discharge range, the -flow still tended to concentrate on op.e side of the stilling pool.

· Revision No.· 4. Th,e studies made ·with the previous arrangement indicat.ed that the ridge should extend over a greater length of the tunnel if it were to be. effective in distributing the flow when one gate was closed. Therefor·e, a ridge 7~1/2 inches in'height and extending from the gate cham­ber to the origin of the trajectory curve was installed in the model, Figure lOd., This scheme improved the distribution of flow when one gate was closed.·_· The flow was comparatively uniform at the downstream end of the tunne1 when either one or both gates were discharging. Upon leaving the. ·-· tunnel, however, the water tended to concentrate in the center of the still­ing pool. Thi~ was especially noticeable when the gate (or· gates) were re­leasing the maximum discharge. ·

Revision No. 5. Since the flow distribution at the downstream end of the tunnel was satisfactory, it was believed that the concentration of flow in the center of the stilling basin could be improved by lengthening the hori­zontal section between the end of the tunnel and the origin of the trajectory curve. Thus, the angle of divergence of the training walls we:mld be less and the change from the 8-foot 9-inch width at the tunnel to the 25-foot stilling basin would be more gradual. Revision No. 5 consisted of lengthening the horizontal section from 20 to 35 feet, Figure lOd~ This change gave satis­factory fl.ow distribution in the stilling basin at all discharges. The hydraulic jump ·was very stable and the full basin width was utilized in dissipating the jet energy, Figure 12.

The Recommended Design

The recommended design, evolved from the preceding studies, is shown on F1gures 13 and 26; This design includes splitter Wall No. 3 des­cribed on page 6 and stilling basih-Revision No. 5 shown on Figure 10d. Figures 12, and 14 to 19,· inclusive, show the operation·ofthe model for one and two gates open with res'ervoir·'elevatidn-4070 and also the flow conditions with one gate 25-, 50-, and 75-percent open and the headwater at maximum elevation 4128.1.

7

For the purpose of determining the height of training walls required and to evaluate the flow distribution in the stilling basin, water-surface profiles were measured along the center line and each edge of the stilling basin, Figure 20. Profiles were recorded with one and two gates operating whe,n. the reservoir level was at maximum elevation 4128.1. These pro­files :indicate that the distribution of flow was satisfactory both upstream from the origin of the trajectory curve and· also in the stilling basin itself.

The results of scour tests made on the recommended design are shown in Figure 21. The scour indicated in Figures 21b and 21c resulted after operating the model for a perio<:I of t4Iie equivalent to 2. 25 hours' pro­totype at discharges of 750 and 1, 500 s_econd-feet with one and two gates, respectively, open. The maximum scour under these conditions occurred immediately downstream from the end sill and amounted to O. 7 foot in both cases.

Three regions of the outlet works were investigated for low pres- · sures. Four piezometers were installed on one side of the bellmouth en­trance to the gate chamber. The piezometer locations and the pressures re­corded at each point are shown in Figure 22. Pr.essures were observed for a range of discharges varying from 300 second-feet with one gate closed to 1, 500 second-feet with both gates operating. The pressures were all above atmospheric within the range of head and discharges tested. Thus, no ad­verse pressures are anticipated in the bellmouth entrances to -the gate· chamber.

Two piezometers were :installed at the high point of the ridge 41 and 80 feet downstream from the gate leaf, Figure 23. These piezometers were used to determine whether adverse pressures existed on the tunnel in­vert where the jet crossed over the high point of the ridge. Pressures measured in this region were all above atmospheric for the range of dis­charges tested, indicating that the reduction in pressure was insignificant due to the water passing over the ridge.

Eight piezometers were placed in the stilling basin at 5-foot inter­vals along the center line of the trajectory curve. Pressures were recorded with the reservoir at elevation 4070 and at maximum elevation 4128. 1 when two gates were operating and also at partial openings when one gate was closed. Results of these tests are shown on Figure 24. The lowest pressure, O. l foot (prototype) below atmospheric, was recorded at Piezometer No. 3 when both gates were discharging 1,500 second-feet at maximum reservoir elevation. Therefore, the trajectory curve is adequately safe against cavita­tion.

Head Loss in Gate Chamber

As an aid in determining the size of slide gates and tunnel required to pass the design flow, the loss of head in the gate chamber was measured in the 1:20 model. The losses were determined from two piezometer rings-­one located in the tunnel upstream from the gate chamber at Station 7+25. 33 (Section 1) and the other in the reduced section of the gate chamber upstream

8

from the slide gates at Station 7+45. 83 (Section 2), Figure 25. The curve shown in this figure represents the total loss of head between Sections 1 and 2 for different discharges with both gates fully open. Since the model was relatively small and was built for purposes other than determining head losses in the gate chamber, these data should be used with caution.

Method of Prototype Operation

It is recommended that, whenever possible, water be released through the outlet works by equally opening both gates. Although the still­ing basin performed satisfactorily when one gate was discharging, the model clearly indicated that, for any discharge, the flow was more evenly distrib­uted in the tunnel and a more uniform jump for med in the stilling basin when both gates were discharging an equal amount of water.

The models also indicated that subatmospheric pressures may occur in the roof of the downstream gate frame at gate openings above 98 percent. Therefore, except in emergencies, the slide gates should be op­erated at openings of less than 98 percent.

9

lnlerlot- • ReclamaUcn • Deanr, Cola.

VICINITY MAP

INDEX MAP

10

FIGURE 1

EXPLANATION PAVED

IMPROVED

DIRT

20

SCALE OF MILES

UNITED STA~ES DEPARTMENT OF THE INTERIOR

BUR EAU OF REOLAMA TION

MISSOURI RIVER BASIN PROJECT CHEYENNE DIVISION-KEYHOLE UNIT-S. OAK.-WYO.

KEYHOLE DAM LOCATION MAP

, \ \ I ( 51,,//woy. .. _____ _,.

FIGURE 2 REPORT HYO.

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surface.--·'

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z 4 I 00 0 . > w

1&1 4000

~~

~-'--Reservoir area

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Uox. WS. El. ~~28.2-·;J_

ol:i

-r\ 0 ·:-~~ ;: ~ •:,,,,~;

N WS Et. 4099. 3···,

--El 4092.07"

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·-·-Assumed rock surface·-· -··

SECTION A-A

GENERAL PLAN

SCALE OF FEET

~a;~~

15~ A Line--··· 6" 8 Line--··

';'Grout holes

i,-{

./L JJ. •}?!'."'··· SECTION D-D

SUPPORTED UNSUPPORTED

ABUTMENT SECTION

r·-Ax1s of dam

:,<-30·~ 2' R1prop ; 1 : L'

Mox WS Et 4128.2· ·y ~

____________ ·,j_

J-$; Assumed rock surface

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;· Shole .. ,..,.. MAXIMUM SECTION 50 0 50 100

Ax,s of dom---,;J .. ~--- 3~'

15'·­{'Crown ···

SCALE OF FEET

... •S0~~~~1W1JJ~~.2"

'It'; Structural steel nbs / ,,

and !mer plates-··

SECTION E-E SUPPORTED UNS'JPPORTED

Sta 4+00. w- -···">;

CREST DETAIL

ON£

Firm -, rock

3'Mmin ?.Itt:; ._:·1-l:· sound rock--··, 0 .I

Gro~t holesotopprox·'l. ><-~~; -.~ Jifl'Jtlm 20 crs as d1rected-- .. __ .ff,:, \j ;}'-6 Av.

GROUT CAP Note: Grout cop to /Je extended If directed

-- Assumed rg:* surface

L .... t, 40t8.4T-'-',-.'f's: E ~ Sfo.t01- 9ioo··'sto.12-+16.00J·

OF OUTLET TUNNEL 100 200 ~

SCALE OF FEET 4200

---<:--Original ground surface -=---==------ N. ws. El 4099·3··) ----- ------------- -------- ~----:_-__-_-_-_-_-:.:::-_-- ~\\f, 41 00 z 0

Min. WS El. 4051. o----·~ . ··- '--Grout cop , 1

I Outlet tunnel·---·- .. / ' ~--====--2--=----- rSmdsloneoutcropsincenflrthirdofemlxnkmenttobe Assumed rock surface if directed ', I

_ .. )f,i- - / / / / ------- .... ~ed lo J:J slope before placing till. : '·Bottom of Sandstone and shale-.·~-:,.. , / / ...,,.;:1...-50 nd oTN!_,grovel·-~.:-,-·.,,, ____ ';flssumed r_ock ~urface ·-Gro~t holes@_ approx. _ :·, _...,, cutaff trench

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3900

Shale~-,:.: -~ ____ ,_L.l _________ _

35 30 25 20 STATION 15 10 5 0 3900

PROFILE ON AXIS OF DAM

SECTION B-8 30 60

SCALE Of' FEET

·--Toe dram

' '

0tmper;,::~::::,';:!7s~ect;::,o~,~::~~:';ovel

0/e~'::u~'S:af:r;g/t;nls;~e%f:Jc:a:Je;;d grovel compacted by crow/er type tractor to 12- inch foyers.

RESE~VOI~ C4P.ACI TY 100 200 500

so""RVo,~o;"' "~ I

6 8 10 SPILLWlY DISCHARC,£ IN THOUSANOS OF C.F.S.

4 e 12 1e; 20 OUTLET OISCH.ARGE IN HUNOREOS OF C.F.S. 6 12 18 24 30 OIVE~SION DISCHARGE tN HUNOREOS OF C.F.S

AREA-CAPACITY-DISCHARGE CURVES

RESERVOIR DATA Super storage 288,360 o t £1 4111. 4 to Et. 4128.l Flood storage 140,000 o.f - Et 4099.3 to El 4111.4 Irrigation storage 130,000 of- El. 40181 to El. 4099.J 51/f storage 70,0000.f- Et. 4016 to £1.4018.7 Dead storage 9,100 o.f- El. 4016 to El 4051.0

UNJrED Sr.ATES OEF',6dtTMENT ()F THE 1NTElfl01'

SU1'EAU OF ,rECt.•MATION

MISSOURI RIVER IIASIN PlfOJECT CHEYENNE DIVISION-KEYHOLE UNIT- S. OAK.~ WYO.

KEYHOLE DAM GENERAL PLAN AND SECTIONS

: Olf,/jWN

• TlfJICED. ~.,_.._.,_..,.c,..oco ----:::re.-"•I.. ~ CHECKED-- ZVJfJ.f._t~ .A-/fOVEO ---- -11,,t'c"Hi•-;I· - ,

~ ~N~lf. CO(.OlfAOO. •uo. , •. ,... .-ne -.

T----='f ix,

! j _____ _

~~

-i

~l

;f,»r'•J \--<: A I I

[ (Sta.10+91 : : Q, 1500 cJs max : :d,375±n,013 ~--""'~ V=46.3 1/5 : : EL Ft 4017.80 : ,_S,0.003

Theoretical tratectory at_,,,/ //, maximum Q, x, 133_3y-- //

/ ---Design trajectory for spreading jet effectively, X'171.7Y-----------------

TABLE X y

5 0°1 1'11~ 10 0'·61!5/18 15 1

1

-31½& 20 2"-4"

25 3'-7'tl6 30 5'-27/

1

35 7'-,·¼~ 40 g'-3 1~

45 11·-~

' /

SECTION A-A

' ' ' '

' ' '

///

'

=+ .!;lj

_____ .;--1"""====+··-:r··· , : N J___l ' i"'""==--....J N ~ :i ···t-·· i i ~ i B

+----~~~---J-·· _i+j : -==--1 ___ , U)

:-r ---r-- -~ J f · i 1~ . ~--.-====-+· ·f·· i B

--~ !

,,,- El.4006.00

.··6

: . :o

'"---r;----Side slope 2:1----\.'--.._

C:.,.. r Lq C:.,.. ~3co"+------J_ u· . -------------1~-6 .. "gi -- ----------+--------·

-.---- . ' --T (<i. Stilling basin

tEft l_r_ Ht' ·-r ' ' =o Symmet . - ' "o .• rical a ,, -J,- ,--, "' bout i---- ---- , "' --- / Riprapnot h , " + ' '~·-----

·' •' : f -i ' ' ; nl+ ' ' rcrl ;( / ' ~

:: ! __ ,,..,,. .. ---t:J

y;;,----·Side slope 2,1.,···.,J,;..,.-

PLAN

.,---El. 4028.00

Approximate tailwater for maximum Q, EL 4022.00---,,

FIGURE 3 REPORT HYO. 338

~----·End of rip rap

.? .,,.-- -+---- ---+-

"'

--------- ---------------------------t------ -10'-d'- -- "---->i

'

6''-:-: k2~6~ : \ I t :r·-~·:::~-­

"' 11 l N

,;,},.~l\ll~T~-

Side slope 2:1

El.

! ,,-·El.4013.00 :/

' 0 •

111,I I I I I I I SCALE OF

,o

L.L.LJ FEET

SECTIONAL ELEVATION ON i OF STILLING BASIN

as for sides Same curve black.----~

of downstream \ ... . .... i

i·~- . i :]; -~:.-'.}.' .·:0·,

Q

SECTION B- B U.S. BLOCK

£ SECTION C-C

D.S. BLOCK

,.-··Approximate point of tangency ./ for downstream blocks.

~x~ \ ~------- 2~2t~-------------~ I I ' I I I I ' I I

__ y ___ j __ ! __ \:__ __J

>- ' ' ·r-···t·-- ·

Symmetrical about i of block,-.\ Qrigini

SQUARE BELL MOUTH CURVE

X

d-o" d-½i, d-'14'

d-1"

d-2½,'

(j-51~

o'-11¼ 1'-4'~

1'-e½' 2'-1½,'

y

d-5"

d-4};

cJ-41~

d-3'._>,,;' d-21;,.

o·-r~. o·,-,,. oc~;; d-1;,; d-d'

KEYHOLE DAM OUTLET WORKS

PRELIMINARY DESIGN OF STILLING BASIN

~--------- 41-'rt--------.-!

f

LL ~

~ Rock baffle .. --Metal pipe

I '-----

"o

r­;;, !l

4 ~r . --Gale chamber

.---Plastic pipe

L'F===='I===="' L.-----------5.~5·----------.l

SECTION B-B

~ ;;;I

4' t-"'··------4'-ff---------·

y j Glass panel---":.I

~

PLAN

r··-1 ,::, !l

_ 1/c}Plastic

L.11 !' 'I I' L..-1.95•-...,.!..,_35•,,l.. ,_95• _.J

SECTION C-C

~t D In D - D • D

I ------------------

A

;;;I

4,

r--------- s·-o·t ---------,

i~!-•5""i I ' .1 • .-, i - zsr- ·. I : ---Pea gravel

SECTION D-D

------r .. !

IJA! I _____ t_

·1· ,-2-1.95" l.95"HP slid_egates ,-Glass panel Toil water gate---,,

l/ .----Plastic pipe / _-,----;;:;-::::::;;;---::;wllllllll \

1 .,...--Pea gravel----,.. ! .... --Loboratory floor

-------------1:i-4.s'-~-------- ·>+<----i:-o·----,---------------·-··········----------- ---------37!.. . ..,_ _________________ _

MODEL SCALE IN FEET

I I I i 4ol00 40

PROTOTYPE SCALE IN FEET

• i

SEC'l'.IONAL ELEVATION A-A

KEYHOLE DAM OUTLET WORKS

THE I: 20 MODEL

0 2 4 "

MODEL SCALE IN INCHES I FOR SECTION$ B·B AND C•C I

~ ., .. ....... o~ :u-G> --tc· :c::o· ~r'I ... "'" ..

4022

4021

4020

I-ILi . ILi IL 4019 z II.I (,)

~ § 4018 a,

a: II.I I-;

4017 IL 0 z 0

fi 4016 > II.I ..J ILi

4015

/ I

I I

4014

40150 200

. .

~ ~

.. / ·/

/ /

400 600 800 1000 ·

DISCHARGE IN CUBIC FEET PER SECOND

~ ~

1200

~

00

UTLET WORKS

R CURVE

1:20 MODEL

:Ill

~'Tl ·•0-

:111 G) -4 C: :c :u ~!Tl c,a UI c,a CD

From pump

............. ···· 2' 6" ·····-···-····· ···<>t ' ' ' ' L '

•. --6" Supply pipe ,'

I

straightener

PLAN

4", 4" H.P. Slide gate-.\._

~··-----··· ···············- 20' o· -- ·-· - ··- · ··- · -·· .. ··+-----····-12"--·----·-t3r ;° ~~ct '

i I I I

--- -:-- 7( )' I I I I

01

ELEVATION

1---i \_ ·~ .... () : .. f Plastic ·-----Tailbox for returning

.,-Piezometers /

--r =~ .,,----·

water to supply channel.······:~-:.: ·--.'I.

PROTOTYPE SCALE OF INCHES 0246810 I I I I I I I I I I I

I I 0 ,5 I

MODEL SCALE OF INCHES

r::;.~:c·;;":'i,;:•':•:'~'''·'"",. :~_:,,:·:,o,_c:,.~.::+,:;t.~:\t<:;s.s,_>,,;,::"~;:\@:Ss@l',•V:t?i.f~

KEYHOLE DAM OUTLET WORKS THE I: 9.75 MODEL

:u '" ..,.,.. o-:u G) .... C: :c::u ~JTI

::: en ..

FIGURE 7

A. Fin downstream. from gate chamber B. Stilling pool operation

Both gates diacllarpag 1500 second-feet Reservoir Elevation = 4128.1 feet

C. Unsymmetrical now in tunnel D. Flow concentrated on one side of basin

Right gate discharging 750 second-feet Reservoir Elevation - 4070 feet

KEYHOLE DAM OUTLET WORKS · Preliminary design

1:20 Model

FIGURE 8

B. · Gate 100. 6o/o open. A. Gate 1 00o/o open. Jet free of gate frame Jet clings to roof of gate frame.

C. Gate 101o/o open.. Jet ap.in free of gate frame.

KEYHOLE DAM OUTLET WORKS Mazimum. discharge through slide gate

1:9. 75 Model

r-•,l, .---Downstream end -.;, of gate frame

i---,. ~~~. :T 1;,j _____ =J, _________ ,__

r-- ' -r·~-R=6u -+

t_, /4'-s~---~~., ... ~.,, .. · ,,,,ii, ,.,,.._,._: .. ~ ..

·-.. ,~:::::1:·:::~-- :i:=;.::=.lj:: '!::·:~-::;-;:;'.;::: :,_ '.;~f:;:;::;':j(-~:::'J~

PLAN

·:..:,-

H@••7•1i ,-;-~:-:);."·1;,_· ._..._ ;::r-~·_-,_-. .cf,_'L'; :&:fi':i. )-:-~·-i·

~~

i ... ~::~:=9 ·:·:·:?:';'\.'."''~:~-~-·c;i:·;,:: .-··!\·;:'$:"]T"'.1::1;:'¥"' --~---·.:-ji:-·q·-1>:··,

ELEVATION

A. PRELIMINARY DESIGN

l-- ~·--·i:,( -... -. ~- -----~-.:,-.~~_::~-:~:;:.,::.:~=-.:w :s.·. tj..,,4;,: .;;.:.~::x::,~-:-;;.:-~·.x,. ~-.,:.·.·.;,;. -~-·-:,:·::;.::~:,r!':;··a:~-.i:

:+

tT:\;~t:~'/:;~:;\ '$}~:'~?,Wi'.}~:~.tt~'c:s:;~JT· ,.·c.: · ,--R•4

" ·--=; •.:, 1a-··Downstream end l -t of gate frame l :J ___ ::i:-.:~::::~:;::~·-?!-'.•:'-~.:-:;::,;;::::::::::~:;::;-_:;~::_: !( ::~:::i,::::~::::i·:::::::*::::-:f::-t:::?.:: ;:,:::::f:::-::::::~::::~:::~::::~f :~:=:~::f ~;::~:::'.'!=:~::::i,,:-

~ in + ....

P LAN

,:·:·q:··-·,··•:t.·.:q;·.:-t::::,;.:.

.st-::,1 _______ I ;;;~

-<-------~;------Splitter wall

. ' -IN .... _, ....

\}:-_:_~:~:-~~- :'·:··-~-:},:::)-.::~:.:~:~:~ ::_ .•. :-~.:-A':::-:\·.}~·.=-:: .. :-::::~::::~:-::}_::-/::~-.:::~::::f:}J ELEVATION

C. WALL NO. 3 ( RECOMMENDED)

~ iii + .... i <n , __

::;:'!'::~.=:;.:: ~::~;:;o;:~:~::,:~~::-:-::;:~:;:~-~;½·."'.:·,· :::;::.:;::.;; _;.·.~:=i:>// ~:.=::i/~\~::::;~::j::/:~:

..--R•4" •+ -·-t--~ - - -..,

cf""'··~:-:-+,:"l•:.":N(.'.~:-."~ . .->: ~--~- .... :~:- ~---~: .. :~_:_._:-... :.~_-

PLAN

::.'Q";::;,::~::::.: ;:~'.::":.;:_:_:-:"#: ~=~:::---~=::~ .-:;)r:::::::·t;:::::~-::~::::{·~ •:•tr. ·-:-:..-::L:~:ii:I:.i

:----- - -- - - --- - - - - - -- ----22'-9"-: __ - -- - - -- -- -- - - -----1 :.;"' ..... _,

r .-:-::.·_:9:}:;:l::

ELEVATION

8. WALL N0.2

' '' ' "' • __ .t.

~-··:;.;;i.: ·: ·-· :_; .·:. /:.c:i(~-: ·;;.,. "•_.)";~·;""<:all·:·· ·:·4 ':/:" :r..,(:. · ·.Li ·:.;::;.;:;;q, ..... :·~·:":'ii,·,::~: "/4 ": _. .::;::'-':'"-.• •:b--. ~

•. ··R•4"

,.';?;1/_ ~ •' a, -1---+--

-.~:-:::~:::~:::~:{:}:;;p:;:{:;~:_•.;:~:::t,:;:,:,::. =~:_:~:_:;::::_I":::_:;?!::•,:"~::::~;}::;;.::,:~:)?-/:~:

PLAN

...... _ ·_ .. · ":"':·: .:.w.-:-:,;•:•4;_:~-.-. .v-.:.:_.,.,., ..... _.,,._. -•~-- ..... _:q._,;.,s;-:-~---.;-:•1i}-1

_. : ------14' Ou-·---·------:

~ ... -,.9--·-Splitter wall I -~ ~~ .... _,

r . -~;~:~:::-:·:·~:-;..;:;;;;_~=~:-:-9-:-:+:--:--(:•:~:p::-:-f.-:;"::;::::t-:::·:O:·::·.<f-·-;,·:'!-:·."k(·:~·:·~----~-~=-:~-~=:":::~::·!:··.~-:~::·!/~\ ...

ELEVATION

D. WALL N0.4

KEYHOLE DAM OUTLET WORKS VARIOUS SPLITTER WALLS TESTED

I: 20 MODEL

:u ~~-o-:u G). -tc: :i:::o ~m :: co ...

i -i

, •• 3~3·,3·~3· Slide gate ••• 3~3·,-t·'S' H.P. Slide gate

~.E,C;rLOJII f.."."~ .$~en~~ !&~"-

ii ~!

}. , I [ :

r I f~ I

:..-ir·~ L ....... 20~ ••••••• ., PLAN .._ -..·

~~--.. ll rl:I C--+-P1 ' ' ' ' ' . P.~A,t,I ~------16~----..... ·---151------~ I ' \1

A. REVISI.ON NO.I B. REVIS:ION .~0.2

•• ··f3"•3:'S'H.P. Slide g9te .•• -·3~3-~ 3~3· H.P. Slide 9ate

~E~TIOI\I !- ~A s~.cmg,,. A~A

i~r· .. J,l I· · a · 1 . I,-

iii . ~f t~ffi~ 11 · ·, KL .

C:~.

~-----------~o'------------>1,.-5~ -. 1 :,.. .. 7~--l k-·· Id ·,...l .

PLAN r' I ,,~ 1·(

C. REV1$1Q!l,l NO.~

~-------20·--------..:

KEYH.QLI: Ot\M QUT~l;T WQ~~§ R~v,~1pf-i~ To !MPR,oyg F!-QW l.)l§TR.l~IJTIQN

IN $TILLING BASIN

I: eo MODEL

PJ,.A'11

Q, REVl$19N N€>§, 4 a 5

$--:,i -:z I~

;.:JP lfP.I

iii

FIGURE 11

A. Preliminary basin B. Caballo type bump installed

C. Both gates discharging 1500 second-feet· with hump installed.

KEYHOLE DAM OUTLET WORKS Basin operation with Caballo bump installed

1:20 Model

A. Flow in tunnel

B. Flow distribution in stilling basin

C • Stilling action as seen through window

KEYHOLE DAM OUTLET WORKS Both gates discharging 1500 cfs.

Reservoir Elevation = 4128. 1 feet. Recommended design - 1:20 Model

FIGURE 12

I I I I

I I I ~ I I ~ I I ~ I I "' I J t I I 1 I

I f I

., .. ::

o, .,

~E69,75o

~~ ~)

"' L-' =:c:::c:£~___'._,~~_;_;,___--..~_2::~$~~D ::} 1 ,.-Inlet channel---C: _.,.. ___ ~f--+-f-+

/:; --c ~-,,-£1.40200----

/ !_._-L..J........L...L__L_.._.L.J-,l--1_.J.-> I

f Side slopes ¼ 'I in rock and : ,/

/ I 1/2: I in common material _.,1,-

/ I

/ I

~ (\,j

)

(<{(. _,.--£ Outlet wrirks N 7•I5'w

-=.-;:f.T

_,, __ ...... I I J ,.,, ..... I /' _____ ....

, , ! ___________ ,,

1 ,--·

I:: .g_~ : t ..... ""- 0 1

,,,, __ \ ,r- ->> CS"') ~ '" ' ~~ ~ °', o.\1.

,- I -\---, ,-'~1 ., .,. ' ,, ., -- - _, ___ ,. .' .,;~_ - - . • C,

,, ,' ~

/ ~

PLAN

Max. W.S. El.4128./----_·::::,.,....,,......,.,. __ _

r.-Axis of dom

,,=w i .__f~/4134,Q

~ £140250--~ V') E.....,_. V>

., ~ .

---------e /_

C, .... la o; "" • 1-

S? ~

,.Outside of tunnel to be formed from rock I face downstream to tunnel por to! Tunnel ' woll to hove uniform 15" thickness. ~I~ "' -- . ~ ....

Narmal WS. El 40993, Assumed rock surface--,, ===-=-=--- ----- -- _ -~ - - - --Original ground surface ~ ~

<o

"' . <o

,-Inlet channel ( El 4020 0

Pipe or drilled holes in funnel orch for placing mortar or grout by grouting methods, location as directed by con-tracting officer. ____ _

Location, type, size, and spacing of structural steel ribs, liner plates and IO()ging fo be as directed or approved by the contracting . officer________ "'-~-~, ---· --- ,.,, ..

Structural sfeef [ibs---=~-:_-_- ;_-1A1L_1ne-- ... ----,L .·

8 Line---- I Liner plofes or lagging----~:-,

~~--

.!,; 0 Troshrack sill "'~J

£1. 405100------..,_

8 ~

l;

,,. ; I

t(l ~ -E! V>

Ar"' ,,-5=000291

~ ~ ~

I I q_ £14019./1-

,E 6:o• Dia. access shaft ..._________ .B 40BOfJ

/ ,'f.J8~o· Gate chamber

/ ,4-3'6~j-6"HPgafes '-' Splitter wail ,--Ridge in floor

E/4018.78: f Br'" ,--s. 0 000292

-, --i-1 ,: AL:- .. ,,,.,:=,v- I I I

I I I '--f Upstream tunnel I I _,,.I ,-; E;i,,

' ~ E (r/l:J~;"g';';;t;;•=;,~ \<;: D~wnsfream funnel

20:tdeep (@ 2o't crs. approximotely

f--', Groui- holes 20'± deep (@20°J: crs.------,.-~-, ~ :Ii . . i ~

Sta 7 •80 to Sta.I0•80 Incl

ScCTION B·B SUPPORTED-UNSUPPORTED

PROFILE -ON£ OUTLET WORKS 'P ~ 510 'C?O •r , , zyo

SCALE Of FEET

Fl

~

TYPICAL TUNNEL SECTIONS 10

SCALE Of f E ET

V> "' ~ V> ''

"-.t.

<o <o - . ~ ~ ~ ~ ~~ttl ~ 1 E ..._ , ;

S..: ~-~ : ,Approx.MaxJW. .--E/402~00 "'!_ 'O.: £14022.0--,

' ',E/4013.0

,-4"R

.:;! V>

~F

:·.-·.·.~-=i

E/402264-. .,..-Sta. 7•'15.75

z 0 I-.. > w _J

w

w u .. "-a: ::, (/)

a: w I-.. ,:

a: 0 > a: w (/)

w a:

FIGURE 13 REPORT H\'_p. 338

-Assumed rode surface

Embankment---, Ground surface- - : -

SECTION C·C

DIVERSION DISCHARGE, C.fS.

1000 2000 3000 4151

J J

4101

/ / Outlet works discharge curve- -- -/ /

V /

/ V / ,/

40~0 I~ /

/ .-El. 4036.0<. J< Diversion discharge curve I<".- 11 ~/

~ -,.,- 1_ Outlet works tailwdter 1curve

4000

.. ~CQ, .... 11:<,;

500 1000 ISOO

OUTLET WORKS OISCHARGE,C.FS. TAILWATER, C.FS.

DISCHARGE·TAILWATER CURVES

NOTES Following not shown, Reinforcement, electrical conduits

and apparatus, reservoir level gage and piping, high pressure gate control piping and opparafus, gofe-chamber ventilating system,air inlet piping, metal ladders,grate landings and handrails.

Type NI metol seals will be placed in all transverse construe­hon joints in tunnel.

All concrete will be designed for 3000 lbs. per sq. inch compressive strength at 28 days.

UNITED STATES DEPARTMENT OF THE INTERIOR

BUREAU OF RECLAltlATIDN MISSOURI RIVER BASIN PROJECT

CHEYENNE DIV./SION-KEYHOL.E VNIT-$0.DAK.- WYO.

KEYHOLE DAM OUTLET WORKS

PLAN, PROFILE,ANO SECTIONS

OltAWN ........ c.r.e ........ SU8AIITTED ... :1'.~~---·· TRACE:0 ...... F,/V..l', ....... RECOMMENDED .. ~ CHECKEo../lJ.t!(__ ,M.APPROVED ... lll'r({J;&_...lt,~-- ...

DENVER,COLOlfADO oc,: ,T,19« 9 I 4 86-0-2 9

A. Flow in tunnel

B. Flow distribution in stilling basin

C. Action in stilling pool

KEYHOLE DAM OUTLET WORKS Right gate discharging 750 cfs.

Reservoir Elevation = 4128.1 feet Recommended design - 1:20 Model

FIGURE 14

A. Flow :In tunnel

B. Flow distribution in stilling bas:ln

C. Action :In stilling pool

KEYHOLE DAM OUTLET WORKS Both gates discharging 900 cfs. Reservoir Elevation= 4070 feet

Recommended design - 1:20 Model

FIGURE 15

A. Flow in tunnel

B. Flow distribution in stilling basin

C. Action in stilling pool

KEYHOLE DAM OUTLET WORKS Right gate discharging 450 cfs. Reservoir Elevation = 4070 feet

Recommended design - 1:20 Model

FIGURE 16

A. Flow in tunnel

B. Flow distribution in stilling basin

C. Action in stillin,r pool

KEYHOLE DAM OUTLET WORKS Right gate 75% open and discharging 560 cfs.

Reservoir Elevation= 4128.1 feet Recommended design - b20 Model

FIGURE 17

A. Flow in tunnel

B. Flow distribution in stilling basin

C • Action in stilling pool

KEYHOLE DAM OUTLET WORKS Right gate 50o/o open and discharging 375 cfs.

Reservoir Elevation = 4128. 1 feet · Recommended design - 1:30 Model

FIGURE 18

A. l'low in tunnel

B. Flow distribution in stilling basin

C. Action in stilling pool

KEYHOLE DAM OUTLET WORKS Right gate 25.,, open and discharging 190 cfs.

Reservoir Elevation = 4128. 1 feet Recommended design - 1:20 Model

FKHJRE 19

a; Q ,g '{'

a; + Q

~

re :l: ~

------ -=~~-

o e 4 s a m I I I I I I I If If

VERTICAL SCALE Of FEET

I!) IO

HORIZONTAL SCALE Of FEET "°

::e ~

!

-·Top of training wall, El. 4028.00

-----------~=

;:: ~

~

<D + !!l!

.e '11

_ LProfile along ~~f basi~

~,; -Profile along left and right

edge of basin.

·El.4013.0

-~Dumped riprap

BOTH GATES DISCHARGING 1500 SECOND-FEET

;:: +

!!! +

!!l!

i ~

/Profile along Q. of basin

~-1..---------=-·

RIGHT GATE DISCHARGING 750 SECOND-FEET

KEYHOLE DAM OUTLET WORKS WATER SURFACE PROFILES

AT MAXIMUM RESERVOIR ELEVATIOI! OF 4128.1 FEET

I: 20 MODEL

.~.~-

/El. 4008.00

,-·Profile along right ~eofbasin.

~~~-=;::== ·'-Profile along left

edge of basin.

-·El. 4013.0

,_.,,~-.v .. ''-·Dumped riprop

:u i;i...., o­:UG) .... c ::c :u ~rt,

"'"' go

FIGURE 21

A. Bed arrangement before tests

B. Scov after right gate discharged '150 eta. for 2. 25 hours (prototype)

C. Scour after both gates discharged 1500 cfs. for 2. 25 hours (prototype)

KEYHOLE DAM OUTLET WORKS Depth of scour - Recommended basin

1:20 Model

FIGURE 22 REP.ORT .HYD, 338

45....-------'----------.---------'-----------,

~ 40t-----t1---"'-..----------,-,--,-,,-, --1 RIGl:iT GATE OPERATING AT MAXiMUM · . RESERVOIR ELEVATION OF 4128.1 FEET

I '-. . 0:: 35t----........... --"<------~'--'---'-----------------UJ . ! " I- 30 ------k-----.J\,-----------------------'----'------l <l r, " :ii= 25 -----1i-'....=..---~"-----------------------

'1 ', " IL. ' "-- Q = 750

~ 20 t==JL:=:~'5,;,Ji =-=~~=?c~fs=:;;:::::::::::==J UJ l5 I -- T---<1..= 625 cfs I _J ~ 10 1-----11---~',....:.·~ .... :::---l-1 __ ---=-_-__ -_-_-_-_-_--=.:-=*"...,.,,........,======~----I

l - ...... + ___ Q = 500 cfL_ · 1 ·-

~ 51----+------+--------==,-==-,._,,,..-'~-....... =====-===~-1-------..L Q=.300 cts · 1.

_J ---·--

J O O'---'--~i.-----+:-::======-=,:==,::===t==-==========-=i------' o:: I UJ J: Cl. (/) 0 :i: 45 1-<I 40 UJ

~ 35 al <l 30

UJ 25 0:: ::, 20 (/) (/)

UJ 15 0:: Cl. 10

5

0

en (.\I

+ I'-

I I I

I BOTH GATES OPERATING AT MAXIMUM

:'.. : RESERVOIR ELEVATION OF 4128.1 FEET

"' I I I.

I "' I I I

r----, " . Q =1500 cts I I

.......... 7 I , ....

L_ i----..5!.:.!.~<2.sfs I

"""""1

I -- I ---...L r---- -4-I -

_ Q=IOOO cfs ---t--------------1 .... Q=600 cfs-- -+--------

_J

' I I I I I

ol ,..;I

..-Roof ot it>I

·7 I

I I

. I I

cl iril

~In .. ,' .

~Piez.No.11

.{ Gate Chamber ;: 1 I cl I ti; I

~I ":I ~· <I) I

' . ·•

'--Piez;No.13

KE YHOL'E -DAM :ouT-L Et ·WORKS

PIEZOMETRIC PRESSURES ON

BELLMOUTH ENTRANCE TO GATE CHAMBER

I: 20 MODEL

I

:'.Piez. No.14

FIGURE 23 REPORT HYO .• 338

~ .· --- . ________ .-41 1--- •. -· ------- --- >k-- _---3g!-----1

- I. - . _.. -j--i- ~. (', .... _,;::.-.-,.-, zr ·, ,: · --· ..... No.,3) .,.;_ .... .:i

-

,,-3'·3" X 3'-i' H.P. i,..,' Slide gate.

PLAN

CE r:s:.lA_....·~--___ ·_··_ .. _·-_··-_: ... _.·.-I'····

"""-'v--Spli-f'ter ·wall ·

•.·• .t, • •. • • .• • •••••• • •• , •• • 0 11:i" ••• • •U.• 0 .•: •• , •••

. ,,·Center ~idge ~:

5 Q: l&J. I- .. <( 4 31: . ' IL 0 I- 3 l&J· l&J IL

• , ••••• .... •· ••• ,.·.· • • ···:- •• ..... • v. • ............. • •• · •.. ~:,t.•. --~ .. ••o•,• ,• • o .......... 1,

"

PIEZOMETER LOCATIONS

o- Bath gates dis~harging . A--- Right gate di1 charging

Q: l&J I-

!S----....... -----.------.------<( IA

. . • IJl--1----4------i--+---+-+---+---I

IL 0

I ....,......- • A ..... v- L,.,,,,, &

1-~---t--r----t--+---+-+-­l&J l&J

I ,...,,, ,,,-" IL ,,....... _;,,,.

Z 21---+--l-+-""7'1'~+--+-+-~ ....... ze1---+---l---+--+--+---+-'-';t-~

'l&J _,,,.. a: _,,,.

~ 11-------1--+-..-+-+---+--+----1 (/) LLJ Q: a.

20 40 80 80 100 120 140 110

FEET OF HEAD ON GATE

PRESSURE AT PIEZQMETER No.13

l&J

~ fa I

"' Ci)

~ -,.---,.---L----r a. o._____.______...___._ ________ ..___.

20 40 . 80 80 . 100 120 140 110

FEET· OF HEAD ON GATE

PRESSURE AT PIEZOMETEf' No.14

K E.YH .OL:E · D ,AM: O.Ui.l ET W.O R KS -

PROTOTYPE -P.RE.$SU;R·E·S AL<tN;G CENTER RIDGE

. · _. t: 20 .. ~ 0 D.E L

4022

4020

4018

4016

4014

4012

4010

4008

4006

4022

4020

4018

4016

4014

4012

4010

4008

4006

,.-Origin

\ ~-! 2 I 3

4

I . 6

I I

1--1,--------------------------···-····,. I

____ _... ..

,.,x2 • 111.sy

'FIGURE 24 REPORT HYO. 338

I I 1--1,-,---------------------------------en~-~...,,..--~---~--i

I I I I I I M--------I I

~ 4 i

/·Origin

:-\:::=----"j I

I I

I I I I I

-·-- ---~.-e"-~~~--+--·--··1"¾"--

I

---------8 Piezometers on 5'·<f centers---------------------------+l

-2 3

--- Both gates 100% open and discharging 1500 cfs. ------- Right gate 100% open and discharging 750 cfs. ---·- Right gate 75 % open and discharging 560 cfs. ----- Right gate 50% open and discharging 375 cfs. -.-- Right gate 25% open and discharging 190 cfs.

I ii 4: t

RESERVOIR AT MAXIMUM ELEVATION OF 4128.1 FEET

2 4 6 8 ~ I I I I 1 I I I SCALE OF FEET

,, ,-, -·

~ -~--:"'

4 .. -~

6 ··~ •• -·x2 •111.6y M"'

7

e"'-- -~ '"-.

' I _I .. +

., ---

l+---------------------:--8 Piezometers on 5'-0" center ~ -. -- Both gates 100% open and discharging 900 els. ------- Right gate 100% open and discharging 450 els. ----- Right gate 75 % open and discharging 340 els. ----·- Right gate 50% open and discharging 225 cfs. --- Right gate 25 % open and discharging 115 cfs.

~ CD +

RESERVOIR AT NORMAL ELEVATION OF 4070 FEET

KEYHOLE DAM OUTLET WORKS

PIEZOMETRIC PRESSURES ALONG TRAJECTORY CURVE

1:20 MODEL

;::: +

m in,., l\l,.,

IIJ~ a: :i:: ~ ... ·c, a: _o LL. l!i

cc

'-

7.0 ..-------,-------------,,--------r------~------,.------.------,...-,r-----......;-,

0)

C CM 8 6.0---------- 0 +

~- l"- aJ CM ..

u C + .2 I'-... ¥: Cl) Cl)

r 5.or-----+---­>

ll I I I~-·· ...

0

~ A.

~ 4.0 r-,-------1-111 LL.

z

:! e 2.0

:I 0)

-~ I

± . ~ ~ 0 I I O --"- .,. ~---3'-3" H.P. Ga-te

-- ,,,,., ' ,, L4_Piezometers \_3 Piezometers

· in ·ring. In ring.

1.01-------+------+------~,C.....---+---------+-------1

00 200 . 400 600 800 1000 1200

DISCHARGE IN CUBIC FEET PER SECOND

1400 1600

KEYHOLE DAM OUTLET WORKS

TOTAL HEAD LOSS IN GATE CHAMBER

BETWEEN SECTIONS I AND 2

WITH BOTH GATES OPEN

1:20 _MODEL

,-Trashracks Dj t<--; -.;-;--1~ -- - --/6 I 6~- - --- --,- -;-:,1

~3-0"'r-t,----tO 6------~3'0<>; _1

___ I I I l ____ t_

I

-;;., ----f

I I

k------ ---------------' I -,

0, I

1,i ---~~ccc---~: --=--=-=---r

-------,25' o"-----------

FIGURE 26 REPORT HYO. 338

' I I .,

_? ~

I

I

i I

L~ .: A Inlet structure ~

~~ ~~" ~ <i~----=-=-------/" Resilient :-=- -joint filler--------- _ _ .-r,,on1:rocnon I

{~ .fl-~' /

: I

: '

1

'rtoor blOCKs;_ k-------1946~------elliptic~ol _; '

i \---- ---Trash'racks----- ---{ '<symmetrical about~ \ - -78ell mouth--- ,_ I

1 : entrance

<> Dr> 'i? SECTIONAL PLAN A-A ~ i-,3-o'!-l<----T-------200-----":1' I 't'' ~ ~ .,...k =x. 71 -.,.,

I Ti __ _ ! -,- ---

-.. -. -.-.-.. -. -.. ·" :i·+·~~ ~-~-;

' ' : : ------------------r-

1

--- I

I f JO Int I ' ' 1 _\ I Sewer pipe dram outlets,,----------

i 1 :O ____ _...,__ --{ Stilling Basin \ A_ k---- <t , - . - --r, ~ I 1

11

I ~ 1-,, ··:---Expansion ;oin/ :<-- io'-o~-- Symmetrical about {----' :+, '\l_

>c--L '? A>

4" Sewer pipe drains---------~

, , corner - - _ J -.'§___L

1~ Hh~ f ' HGl; I - - ' ' ",!, ' L - I

1h t. ~r- - .,f- :it>_. ~i I •,;;,,.:3~0 *{P. '> !I- - I I

;;; .. ~ t( ~ El. 4025.o----,----- ~-~c '~ '" < u ' -- -~-~---- -- -- -

/4 Resilient ioint fi'//e • ~ .-r- ----, • r <ri ;:;:: J I I

'-.q_ 3' Dumped riprap--. __ __ } ____ _

End

I

., c:, -.i, <)< ' I

/ I A :I =I

c'i-! I trM»>};<f?;,,tn . 'o·

'l'

,-- - ---Symmetric.!!/__ '!__b_<:ut { \ --q_ Inlet structure -- -- , \ A

- I 'C

• " ' < ' '

_,_. R,bo,, w,t,;;::, ------ ------. - u ,oz,oo, ~- P L A N __J_,_ __.,.___Ull? ;;

1

I Expansion iomt - ---- -- - - ' • • -----..__ I : : " ,--------. ' -- -------,s'o"-- ' • K ~-

: ~" . . -;, U"":" F •'0" .;;; ii '"''": '.'.".'.''.'.'.'. , .. ,. . ,~.. --- --- - .,-o· _ _ _ _ __ • j "'l _ -4d-o" _ _ _ +-"" J - I ' I : : l I

: -i---:;,;. _L'y' __ _

Stoplog guide/

11 11

1--/"Grout header j 1,,---Metal sepls Type NI

~-,, _,24- A line

·(~~~~i7i~~~~tE1:.·······•i\-t'F3°(B·Line,~·.··W - '-Toper uniformly

-'.·c;i_··

~~

SECTION B-B

F2 4063.50

I

=c.o _, ~ I

_ I 11 r, - . -· ,~1-olTT

i _,

T I

SECTION L-L

~-- - - - -- -- - -16' 6" ------ - - _.J l.,3'-ol!.l.c--5'-3'C- --5C3'C~-3coJ Ar--1 I I I

'I : :El. 4063.50- , : -;r-r

1:1 I ~: 11L-+ --r-: I I I I I

I I I I :

1 1 I : • 1

\1 it 1

1 i:':. 1 -iA I 1 , : '(

11 I I

1 I l I I I : I

Trashrack or -!-.i-'' Stap/ag guide- --Li'-•-

,--El. 4051.00 _y_ E 40 - ll I I I I ,. 51.oqJ __ u~ __ LL

1 =' ~ ::: ~ -il1-

I a' -I <::) I_, I '<)

I _ _£_ ,_ _r,_ _ I <J--- 27.30 1.9/ -

1 I

Br--j I y I

Removable ___ ---~ trashrack-·'.,.,_-- - ---18C9''

...., , I I

El. 4020.00-, : _'t_)'.__

,-Toper : uniformly

' I I

, , -: -~'-Metal seals Type NI ! ~ ·- ------ - _____ / 23'·0" -- - -- - -- - - -- - - --.>k-- - ---- ---- --20' o" --------------~

Goncrete plug to be placed \ ' ' and grouted after diversion-!

SECTION C-C INLET STRUCTURE

'"' I -"/2, I I I

1/\': 1'· I L l rT)1~ 1-~·,..'JyN)·.. -----~ i _nz;·, ~ ------------17' 6" - --------- ~

SECTION D-D

U3 Finish-------\

I I : I I I ' I I : I I I o

: ,-H 4013.0-: ., J. -~:

4"j~7n~~~ :~~~/!e~~-~ ~:;~e~~-c_e_".7_e~_~e_~------~~~--EI. 4006.00 . .~. 7 N y "' ,v~vv:-,.,_, .~------Assumed rock surface

SECTION E-E ~J K

I

r-------------,r-----_,-e::--=::=----;::::".;-E/ 4028 00 I F2F' 'h I { ' r,-----,-------------'--7

I • ' I / / l

1

1amt 1

_________ ·=-IV"_,..,, _________________ , 1 C~c~n~r~::n-1 -~~---:~~---26r~O~~t~~:~~::':_ -=="S7"=>' /J I --~----~ --------- /~/ :

-----+---- 1

1

,.,..,....:,.,..- 1 / /

: I ~------- .---.--- _,.,..J

Embankment--.,-;---->-•,_,

I I . ,,,,,, ,,,,,.,.,, ,,,..' I ,,....... ,....... ,.,..

: ~~k:;k==----j-------,-,c-cc,.,...,k,.,~2; / / / / / / / I ,,. /

Assumedracksurface--,_ 1

--~ _____ , ----- ------1----------- ,,.-----:. t=~---==~-~====-=-:---:------ --------- __________ L ______ +-----------

El. 4028.00'1

->t ~2" / I Wl---L

SECTION F-F

Foating---:t I \ \

1

I I '•-Cut 1off I L- -- ----- -------------- - - - - - - ___ .J_

NOTES Reinforcement and reservoir level gage

piping not shown. ~El-4028-00----- - - ----- SECTION

. . ..... ,~,-, I 12'!.-">i ~- 1

E -Slope tops of ·~·"-_i.-~-F2 r: · h I. 4025.0- II '" d _q_ St'//' B . . ... -<> ~ ,ms

\. ?} la~:.0" f><

1 mg osm :o1-3L-~7~,w-~"_"'_i,-w-o-, -

,f2 Finish

K-K

C ~ QJ·--,··::/J;pt;"/ "'°'" ,;::-.-- --r ";::,-1 1::::) =-,~, -- ' -t-!-,

<o ' - .··:.0:-·.o.·::.·<=1.··

Apply two coats of sealing compound to one face of contraction joints.

Embanlrmenlc,;:j.··.,----- -- -----26

' o·~ lo:\ Backf ill7y1 Y ._. -----13'0~---~·: t

Batter f" {) perfooh •.

·.·Lr'.•: :':--'

~,¾-1/ @:~J./1i:~~=~.::J==:'.l=c 4" Sewer pipe drains with/ SEC TIO N

uncemented joints, _ · embedded in grave/--'

J-J

STILLING BASIN

SECT~O-N G-G CHUTE BLOCK

Elfiptica~/ ,~:=--_ corners· + .:..•_b:-·:.·•.·.-9:

SECTION H-H FLOOR BLOCK

C)

~' ..,

UNITED STATES DEPARTMENT OF THE INTERIOR

BUREAU OF RECL.AMATION

MISSOURI RIVER BASIN PROJECT CHEYENNE DIVISION-KEYHOLE UNIT- S. OAK. WYO.

KEYHOLE DAM OUTLET WORKS

INLET STRUCTURE AND STILLING BASIN

~~I- -----~--;:=-:~~r ,.,., r,~~~~tf!EC~~,~~f'!'1''" -,,----~ --- --1 ~~