0' Lr\

HYDRAULICS BRANCH OFFICIAL FILE COPY

t-r\ ..___~--~--UNITED ST A TES

DEPARTMENT OF THE INTERIOR BUREAU OF RECLAMATION

oFFI C E

F ~LE COPY B! re_ r .:.u OF RECLAMATION HYDR.1·.UL IC LABORATORY

HYDRAULIC MODEL STUDIES OF THE O U TLET CONTROL STRUCTURE, C U LVERT UNDER D I KE 1

A N D WASH OVERCHUTE AT STAT I ON 938 + 00 -­WELLTON-M O HAWK DIVISION

GILA PRO J ECT ~ ARIZONA

Labor a t or y Report No. Hyd- 359

ENGINEERING LABORATOR IES BRANCH

DESIGN AND CONSTRUCTION DIVISION DENVER, COLORADO

J anuary 7 , 1.953

CONTENTS

Page

Summary 0 . . • . . • • . • • • . . • . . . . . 1

Outlet Control Structure 1 . . . , . • • . . • • . . . . Culvert Under Dike • . . . . . . .. . . . • 2

. Wash Overchute at Station 938+00 . . . . 2

PART !--OUTLET CONTROL STRUCTURE

Introduction . . . . . . . . 3 The. 1: 24 Scale Model . . . . • . 4 The Investigation . . • • . . . . . . • • . . 4·

General . . . . . . 4 Preliminary Basin . . . • • . . . . . 5 Basin No. 2 . . . . . . . . . . . 5

.Basin No. 3 . . . . ·• . . . . 6 Basin No. 4 . . . . . . . . . . . 6

The Recommended Design • . . • • . . 7

PART II--CULVERT UNDER DIKE

Introduction .. . . . . . . • 9 Th~ 1: 12 Scale Model. . . 9 The Investigation. . . . . , . . . .• • • . . 10

General . • . . . . . . . . 10 Design 1 (Preliminary) • . . . . 10 Design 2 . . . . . . • . . • . .. . • . 11 Design 3 . . . • . . 12 Design 4 . . . • . • . . . . 12 Design 5 . • . . • . . • • . 12 . Designs 6 and 7 . . . • . . . . 12 Design 8 . . . . • . . . . . • . 13 Design 9 . • • . . . . • . . . 13 :oesign 10 and 1-1 • .. . . . . . • 13

The Recommended. Design • . 14 Water-surface Profiles .; 14 . . . .. . . . Piezometric Pressures . : • . . • . • 14

Culvert ·Pressures • . . . • 1.4 Pressure on the Baffle Piers . . . 15

i

CONTENTS--Continued .

PART m--WASH OVERCHUTE AT STATION 938+00

Introduction . . . . . . . . . . . . . . . . . . . . . The 1: 12 Scale Model . • . . • . . • • . . . . . • . . The Investigation • . . • . . . . . . . . . • . . •

General . • • . . . • . . . . . . . • . . . . . . . . Design 1 · (Preliminary) • . . . • • . . . . . . . • . Design 2Ar- • . . . . . . . • . . . .. . . • . . . . . • Design 3 . . . . . . . . . . . . . . . . . • Design 4 . • . . . • . . • . • . . . . . . • . Design 5 . . . . . . . . . . . • . . . . . . . . . . . Design 6 . • . • . • • . . . . • . • • . . . . . . . .

The Recommended Design • . . . . • . • . . . . • . . . • Water-surface Profiles • . . . . • • . . . . . • . . . • • Pressures on Baffle Piers • . . • • . . . . . . •· . . . . .

PART !--OUTLET CONTROL STRUCTURE

General Map • • • • • • • • • • • . • • • • • • • • • • • Location Map • • • • • . • . . • . . ~ . . Protective Dike No. 1 and Outlet Channel . . • . . . ~ • . • Outlet Control Structure • • • . . • • Culvert Under Dike • . • • . . . • • . • • • . Wash Overchute at Station 938+00 . The 1: 24 Scale Model . ~ • . • . • . . . • . . Operation of the Preliminary Basin Various Stilling Basin Designs Tested Operation of Basin No. 2 • • • • • • Operation of Basins No. 2 and 3 • . . . Operation of Basin No. 4 (Recommended) .. • . . Operation of Basin No. 4 (Recommended) • .

. . • •

. . . .

The Recommended Design • • • • • . . . . • • . Head-discharge Curve • • • . . • . . • • ,. . •.• Water-surface Profiles (Channel at elevation 324. 6) • • • Water-surface Profiles (Channel at elevation 333. 8) · • . • . •

ii

Page

19 19 20

20 20 21 22 22 22 23

24 25 25

Figure

1 2 3 4 5 6 7 8 9

10 11 12 13 14 15 16 17

CONTENTS- -Continued

PART II--CULVERT UNDER DIKE

Details of Outlet Structure . . . . . • . . . • The. 1: 12 Scale ·Model . . . . . . . . . . . • . . • • . Various Stilling basin Designs . . • • . . . Rows of Baffle Piers Tested in Stilling Basin . -• . • . . Operation of Preliminary Design • . . . . . . Operation of Design lA . . . . Operation of Design 2 • • • • . . . • . . . • . . Operation of Designs 4 and 8 . • . . • . Operation of Design 11 · . . . . Water-su,;rface Profiles ,. 1• • • •

Piezometric Pressures in Culvert • • • Piezometric Pressures on Baffle Piers Location of Piezometers in Culvert . . . . . . . . .

PART m--WASH OVERCHUTE AT STATION 938+o0

Location Map . . . . . . . . . . . . . . . . . . . The 1: 12 Scale Model . . . . • • . . . . . . • . . Baffle-Pier Arrangements on 2: 1 Apron . . . . Baffle-Pier Arrangements in Stilling Basin . . • • • . . Design 1 (Preliminary) . • • • . . Operation of Design 1 . • . . . . Operation of Design lA., • • . . . • . Operation of Designs 1 and 2A . . • . . • • . Operation of Designs 3 and 4 . • . • • . . . Operation of Designs 4, 5, and 6 . . . . . Results of Scour Tests for Design lA The Recommended Design Water-surfa~~ Profiles . . Pressures on Baffle Piers ,. ,. ,.

iii

Figure

18 19 20 21 22 23 24 25

26 & 27 28 29 30 31

32 33 34 35 36 37 38 39 40

. 41 42 43 44 45

FOREWORD

As a part of the Wellton-Mohawk Division, Gila Project, the Mohawk and Wellton-Mohawk Canals are used to deliver irri­gation water from the Colorado River to land along the lower reaches of the Gila River, east of Yuma, Arizona. Water is supplied to the Wellton-Mohawk Canal by the Gravity Main Canal which carries the water from Imperial Dam to the Gila River Valley, Figure 1. By gravity fiow and lifts of 27 and 85 feet at Pumping Plants No. 1 and 2, respectively, the Wellton-Mohawk Canal d~livers the water to Pumping Plant No. 3, located about 5 miles southwest of Wellton. At Pumping Plant No. 3, · the water is lifted 57 feet to the Mohawk Canal, which irrigates the land along the Gila River east of Pumping Plant No. 3.

The Mohawk and Wellton-Mohawk Canals cross several wasJ1es~ which are normally dry, but subject to fiash no·ods during periods of heavy rainfall. To evacuate the fiash floodwaters and pro­tect the canals from damage, a number of wash overchutes, siphons, and protective dikes with outlet structures were constructed at the washes and along the upwash side of the canals, Figures 2 and 3.

This report covers the hydraulic model studies made on three of these structures, namely: the o_ut.let control structure, Figure 4; the culvert under dike, l F_i~re __ 5;_ and the wash overchute at Station 938+00, Figure 6. The studies on the three structures were conducted more or less simultaneously and the results of one were applied to the other two. Each of the above structures has a baffied apron, :plac~g on a 2: 1. slope at the downstream end of the stilling basin. The baffied apron is designed to lower the fiow from the stilling basin to the outlet channel with a minimum of scour in the channel. Since the channels below the structures are expected to. degrade, w~cl!.P..!'.~.cJ.E:_de~ the use _of a fiip bucket or conventional stilling basin,1 the baffled apron extends below the channel bed to pro-

. vide adequate protection against a major fiood. As the channels l~e; · gradewithsucc;:eedingfioods,, the baffied apron may be extended down­ward, as required, to protect each structure.

The three structures are covered separately in the report. Although only a particular structure was modeled and tested, the . studies covered a wide range of flow conditions so that the experi­mental results may be applied to other structures of similar design in the project .

UNITED STATES DEPARTMENT OF THE INTERIOR

BUREAU OF RECLAMATION

Design and Construction Division Engineering Laboratories Branch Denver~ Colorado January 7, 1953

Laboratory Report No. Hyd-359 Hydraulic Laboratory Section Compiled by: W. E. · Wagner Reviewed and ·

checked by: A. J. Peterka and J. N. Bradley

Subject: Hydraulic model studies of the outlet control structure, culvert under dike, and wash overc;hute at Station 938+00-:.. Wellton-Mohawk Division--Gila Project, Arizona --

SUMMARY

Included in this report is a discussion of the results obtained from hydraulic model studies of three structures, namely: the outlet control structure, the culvert under dike, and the wash overchute at Station 938+00. · A model of each structure was constructed and tested. To avoid confusion in presenting the results, each is discussed under a separate heading.

PART !--OUTLET CONTROL STRUCTURE

The hydraulic model studies discussed in this report were made to calibrate the control slots, to determine the performance of the still­ing basin, and to check the effectiveness of the baffled apron. The re­sults and recommendations are based on studies conducted on a 1:24 scale model, Figures 7 and BA.

Four stilling ... basin designs, which varied in length and location of the basin, were tested. Each test basin was fairly acceptable in performance, and the stilling basin studies were con:.. cerned primarily with determining the optimum length of structure without sacrificing any of the efficiency of the stilling action in the basin. The basin length was reduced from 78 feet 6 inches in the preliminary design to 42 feet 6 inches in the recommended design, Figure 9. · The studies also indicated that the chute blocks and basin baffle piers were unnecessary and these were omitted in the recom­mended design. Figures 8, 10, 11, 12, and 13 show the operation and the results of scour tests for the different stilling basins. Table I, page 8, contains a recapitulation of the scour test results .

A head-discharge curve for the structure, obtained by caii­brating the model, is shown in Figure 15, which indicates that the structure will pass the maximum discharge of 7,000 second feet at a head of 14. 5 feet.

Water-surface profiles for a discharge of 7,000 second feet are shown in Figures 16 and 17

PART 11--CULVERT UNDER DIKE

The studies of the culvert under dike were made on a 1 :12 scale model to determine what alterations to the structure, . if any, were required to limit the_discharge to 1,250 second feet at a head of 15 feet and to lower the flow to the outlet channel with a minimum of scour.·

Eleven different stilling· basin designs, Figure 20, were tested in developing the outlet structure to meet the above design requirements. Tests on the preliminary design disclosed that the structure would pass 1, 250 second feet at heads of 12. 5 to 17. 5 feet, depending on whether the culvert transition flowed full or partly full. Since the culvert was designed to flow full throughout its length at a head of 15 feet for this discharge, it was necessary to install baffle piers in most of the stilling basin designs to main­tain the 15-foot head. However, it was found that the 15-foot head could be maintained by using a step 2 feet high at the downstream end of the stilling basin in Designs 10 and 11 Design 10 is recom­mended for construction in the field, Figure 20. Figures 26 and 27 show the oper:ition of the recommended design and the resulting scour patterns with the outlet channel at different elevations. Table II, page 16, . is a recapitulation of the scour tests on all the stilling basin designs.

Water-surface profiles from the recommended design for discharges of 600 and 1,250 second feet are shown in Figure 28.

Piezometric pressures for Design 2 and the recommended design at discharges of 600 and 1, 250 second feet are shown in Figure 29. The lowest recorded pressure in the tunnel was 9. 5 feet of water below atmospheric. Pressures were also obtained on four baffle piers on the 2:1 apron. These results are shown in Figure 30.

PART III--WASH OVERCHUTE AT STATION 938+00

A 1 :12 scale model was used to develop the outlet structure for the wash over chute. The model studies w.ere made primarily to study the acceleration of flow resulting from the 3-foot drop immedi­ately upstream from the baffled apron, Figure 6, and the effectiveness of the baffled apron.

2

Extensive studies of the size, shape, and spacing of the baffle piers-on the 2:1 apron were made in this investigation. Of the six different l:>a~fle-pier.·arrangements tested, Figure 34, it was found that the arrangement in the preliminary design, with an extra row of piers added at the downstream end of horizontal apron, gave \the best flow distribution and a minimum of scour in the outlef diannel. The addition of the extra row of baffle piers caused a hydraulic jump to farm on the horizontal apron which was effective in. slowing the high velocity flow over the chute, Figure 38. The results of scour tests for the recommended design at discharges of 600, 1, 250, and 1, 875 second feet are shown in Figure 42. A summary of. the tests using the various baffle-pier arrangements is tabulated in Table III, page 26.

Profiles of the water surface for discharges of 600, 1, 250, and 1, 875 second feet are shown in Figure 44.

Piezometric pressures on the baffle piers on the 2 :1 apron are given in Figure 45.

PART !--OUTLET CONTROL STRUCTURE

Introduction ·,

The outlet control structure is located about one-half mile southwest of the Wellton-Mohawk Pumping Plant No. 3, approxi­mately 22 miles east of Yuma, Arizona, Figures 2 and 3. Together with the culvert under dike, its purpose is to control the evacuation of the storm run-off waters retained by Mohawk Protective Dike No. 1, which extends approximately 13 miles along the upwash side of the Mohawk Canal, Figure 2. ·

The outlet control structure consists of a check wall with four 10-foot-wide slots, a stilling basin, and a baffled apron on a 2:1 slope immediately downstream from the stilling basin, Figure 4. The slots in the check wall are designed to limit the flow through the structure to a maximum discharge of 7, 000 second feet at a head of 15 feet. This discharge is the maximum flow which can be safely handled by _the outlet channel without overloading the wash siphon at Wellton-Mohawk Canal Station 822+17. 17 or endangering bridges and

· embankments of the Southern Pacific Railroad.

·t1ydraulic model studies of the structure were made to check the size of the control slots, to determine the performance and ade­quacy of the-stilling basin, and to check the effectiveness of the _baffled apron'.

3

The 1: 24 Scale Model

The model o( the outlet control structure was built to a geometrical scale of 1 :24 and consisted of an inlet channel, 6 feet in length; the outlet structure; and an outlet channel approximately 9 feet in length, Figure 7. Since the stru_cture is symmetrical about the center line and to keep the model construction costs to a minimum, only one-half of the structure was built for the model studies. Therefore, one side wall of the model was vertical and straight, representing a plane of symmetry on the center line of the prototype structure, Figure BA.

Water was supplied to the inlet channel by one of the port­able laboratory pumps and was metered through a combination ven­turi and orifice meter. Since a tail-water curve was not available for the outlet channel, flashboards were placed at the downstream end of the outlet channel to act as a flow control and to hold the mov­able sand in the bottom of the outlet channel.

The Investigation

General

The model studies of the outlet control structure concerned primarily the distribution of flow downstream from the notches as it affected the stilling basin performance, the adequacy of the stilling basin, and the size of the control slots required to pass 7. 000 second feet at a head of 15 feet. Four stilling-basin designs. which varied in length of basin, were studied. Comparison of the different basins was made by observing the distribution of flow downstream from the

. notches and obtaining scour patterns for each design. The scour tests were made with the downstream channel at two elevations, 333. 8 feet (original channel elevation) and 324. 6 feet (assuming degra­dation had occurred) with the model operating at the maximum dis­charge of 7. 000 second feet for 30 minutes, which is equivalent to approximately 2-1/2 hours in the prototype. Similarly, the scour tests were used to evaluate the effec_tiveness of the baffle piers in the basin.

Visual observations of the flow distribution in the stilling basin were made for discharges of 2, 000 and 7. 000 second feet. No changes in the size or arrangement of the baffle piers on the 2:1 sloping apron were made, since extensive studies on the wash-1overchute model, Part III of this report, showed that the baffle piers, as originally de­signed, were satisfactory.

4

Preliminary Basin

Initially, the model was constructed according to the preliminary basin design, Figure 4. The model, shown in Figures 7 and BA, was operated at the maximum discharge of 7, 000 second feet.

The flow spread fairly well after leaving the slots in the check wall. There was a tendency for the water to "pile up" along the train­ing wall and between the slots where the spreading jets converged downstream from the check wall, but the water entered the stilling basin fairly uniform, Figure SC. From visual observations, the stilling basin appeared to be much longer than necessary and the baffle piers appeared to be too far downstream to aid in dissipating the high velocity flow. Practically all of the stilling action took place in the upstream half of the stilling basin and the flow was evenly distributed at the downstream end of the basin. Results of the scour test for the preliminary basin, with the bottom of the outlet channel at 333. 8 feet, showed that the maximum depth of scour in the outlet channel was 4. 8 feet, Figure 8D.

Figure 8B shows the model operating at a discharge of 2, 000 second feet. At this discharge, the pile-up of water between the slots and along the training wall was negligible and flow through the stilling basin w-;j.s very quiet with little visible turbulence.

Basin No. 2

Since the preliminary tests indicated that the stilling basin was too long, the length was radically changed from 36 feet to 12 feet in Basin No. 2, Figure 9. In addition, the basin baffle piers were removed, since their usefulness was questionable with a short basin.

Figure l0A shows the operation of Basin No. 2 at the maximum discharge of 7, 000 second feet. The flow immediately downstream from the slots was similar to that observed in the preliminary basin. The operation of the stilling basin was satisfactory, with the full length of the basin being used in dissipating the high velocity flow. The scour in the downstream channel, Figure l0B, was 5. 3 feet--or 0. 5 foot deeper than that obtained with the longer basin in the preliminary -design.

To determine the effectiveness of ·the chute blocks, a scour test was run at maximum discharge with the chute blocks removed, Figure l0C. Results of this test showed the scour to be 5. 8 feet

5

which is 0. 5 foot deeper than that obtained with the chute blocks installed. Since the depth of scour was only slightly greater with the chute blocks removed, and the stilling basin performance was satisfactory. it was decided to determine the proper size of basin without the use of either the chute blocks or baffle piers.

All the previous scour tests were made with the outlet channel at elevation 333. 8 feet. To ascertain the effectiveness of the baffle piers on the 2: 1 sloping apron downstream from the stilling basin, the bottom of the outlet channel was lowered to elevation 324. 6 feet and a scour test run at the maximum discharge of 7. 000 second feet, Figures l0D and llA. The depth of scour with the lower outlet channel was 5. 6 feet or approximately the same as that observed with the higher outlet channel. Thus. assuming the depth of scour is proportional to the velocity of the flowing water. the baffle piers were very effective in retarding·and breaking up the water as it flowed down the 2: 1 slope.

Basin No. 3

From the tests on Basin No. 2, it was concluded that the 12-foot basin length was adequate and any shorter stilling basin would probably sacrifice some of the stilling basin performance and increase the scour in the outlet channel. However. it appeared that the pile-up of water between the slots downstream from the check wall could be reduced if the horizontal floor were shortened. For Basin No. 3 the length of the horizontal section downstream from the check wall was reduced from 26 to 18-1/2 feet and the 16-1/2-foot curved section was replaced with a sloping section 12 feet long. Figure 9. This alteration was made without moving the 2 :1 sloping apron. Thus. the stilling basin was 24 feet long for . Basin No. 3, but the studies were concerned only with the distribu­tion of flow immediately downstream from the control slots.

Basin No. 3 gave an improved flow pattern downstream from the check wall at maximum discharge. Figure llB. By com­paring Figure llB with Figure l0D, it can be seen that the pile-up between the slots was materially reduced. Results of the scour test with this design are shown in Figure 1 lB.

Since there was a definite improvement in the flow pattern downstream from the check wall, it was decided to accept the shorter horizontal and sloping sections between the check wall and the stilling basin.

Basin No. 4

The tests on Basin No. 2 showed t~at a 12-foot-long stilling basin gave satisfactory results. Therefore, Basin No. 4 combined the stilling basin of Basin No. 2 and the horizontal and sloping sections of Basin No. 3, Figures 9 and 12A.

6

With the maximum discharge of 7. 000 second feet passing _ through the model. Figure 12B, the performance of the stilling basin was satisfactory with the flow well distributed at the downstream end of t_he basin. Downstream from the check wall the pil~-up of water between the slots and along the training walls was still evident but materially reduced irl height.· Results of the scour test. Figure 12C. showed the_ µiaxim,um depth of scour with the _outlet channel at eleva­tion 324. 6 feet to be 5. 6 feet, or the same as that obtained with the · longer and more costly structure in Basin No. 2.

Figures 13A aq.d 13B. respectively, show the operation of the model at discharges of 7,000 and 2,000 second feet with the outlet channel at:elevation 333,. 8 feet. At the maximum discharge of 7,000 second feet, the appearance of the flow in the stilling basin was the same -as that observed with the outlet channel at the lower elevation of 324. 6 feet. A scour test made with the outlet channel at elevation 333. 8 feet at maximum discharge. Figure 13C, showed the maximum depth of scour to be similar to that obtained with the outlet channel at the lower elevation. With 2, 000 second feet, the flow through the structure was excellent with no pile-up of water between the slots and well distributed flow through the stilling basin.

From the results ·of the above tests. Basin No.· 4 is recom­mended for construction in the field.

The Recommended Design

A detailed drawing of the recommended structure is shown in Figure 14. In length. the recommended structure is 36 feet shorter than the preliminary design which represents a considerable sa_ving

. in materials and construction costs. From the scour tests. which are tabula,ted in Table I. it can be seen that only a slightly greater depth of scour was-obtained using the recommended structure with its shorter length of stilling basin.

7

Basin No.

Prelimin-ary

2

2a*

2a

3

4 (Recom-mended)

4

Table I

RESULTS OF SCOUR TESTS :nischarge of 7, 000 cfs

.l:!.il of Tail water outlet channe 1,

el, ft feet

340.·7 333. 8

340.7 333.8

340.7 333.8

332.7 324.6

332.7 324.6

332.7 324.6

340.7 333.8

Length of basin,

feet

78. 5

54.5

54.5

54.5

54.5

42.5

42.5

*Basin No. 2 with chute blocks removed.

Maxrmum depth of scour, ft.

4.8

5.3

5.8

5.6 ,

6.6

5;6

5. 8

A scour test was also run ·to determine the extent of scour upstream from the slots in the check wall. Results of this test are shown in Figure 13D. The maximum depth of scour, which was 4 feet, occurred at the corners of each slot and extended from 10 to 11 feet upstream from the slots. Therefore, it is recommended that a concrete slab, 10 feet or more in length, be placed upstream from the check wall.

The results of the calibration of the control slots. are shown iri Figure 15, where the discharge in cubic feet per second is plot­ted versus the head in feet. This curve indicates that the. maximum discharge of 7,000 second feet will be reached at the head of 14. 5 feet in the inlet channel.

Water-surface profiles were obtained at the maximum dis­charge of 7, 000 second feet with the bottom of the outlet channel at elevations 324. 6 and 333. 8 feet. These .profiles are shown in Figures 16 and 17, respectively.

8

FIGURE 1 REPORT HYO. 359

// R.23W. R.ZZW. R.16W. 15 14 13 12 11 10 R.9W. ~

' I I '- ···- - ~ " I II . "' t',Ol)(IQQ, ¥,;,•

-- " " I " . " o r ...-?,. ~ 11 E ~ostleDome # \1 , '---· 11 1 \ ...-Y"1 '{0-.

1--1 / lit~ )fr,r Peak I \ \ . '-- !J. ~ I 'i = -. 7 T,4 s. el h ., Ii t' I'\ l\; k,;"" M• nteiumo T.4S.

~~ ~ . ~ II q~/ #// l-. \~

~ !-e i., _ ~ ~**3/ / \ _ ) ,;;,11':i... I I I I I

T.13s.U-1 bt_~ ~ R.ZIW \\ 1/*v,--- ,/ '\ '\,. 1, _ _,,.t---- II HollWell .,.,,.,,.. I I

I - , _-:::J _J~:,,,!'- U _Ii I ;, II - 1 \ I I I I I

-r-;-~-,-t-.U~,c~ch<t-r 1- ~I\•,, •1k_,*-/ " , , 1 ,. 11 H der.--' ..- i,....~

-1--1--t-L -1---t--1-L-t-- ,':~, ,r )' . '\ \.. ~ Lo~4s i\ II ~!;:ii' 11,- -k~

I I I I I I I l I \"'Ii ,, .,.. I

---l-+-- --,----t--1--,- ,, "' .,,, I " ~ 1 u I . I# --A,,,

I I 1 I I I I I ~ ..... ~ ~ ~ T 5 5 •11 // , II \\~Qcn,;it.a I.Ii, , \. -= ,_ 1 V/

~~·!<-, : +-1-1 -,--,-r- ,,~,, , · // ,,,===========}' 1\ ·['°,,_ Well ' ,,< # I"' Aiuoro,ente

I --...~- +- L I ! L ' :\, ( # ~'f- G\ f/

I-<-:""--+- - -i-,-,-, -+,- p· ,.,.,, // \ I' ),li\fs.1 I I : \I,~ ,,,,,., l,ll9/;c.-,'

n I P1cocho \ 1 I L 1 1 l L ~ ,-fy 11 t'".. ~ ~ ·~-"' · H '

Pl!llk-7- +-r--1 -,-7--+- , - ' R zow.ti/ 19 I/ ,e 17 D,1,. '<r , ""s 0[~ "' , D

,__7 I I I LI I 1 I _l h ·.

~ 5

T.14S. -r-1 1 -T-,7-t ~

0

+-t--'\t-- 7 ---+-I I I //i I I ..-1' I I 1 t 1 1 1 I I I I I I I I I I ·-1 :'\i I II '\, &,;09' :,_ , >j

I I I I I _J ~ I I \I I I -;--,:il-;(-Tt--J---l----#--.J_J_1_ 7 _.L--1-J._L-j--l-T-1-~~ - r-~-.,--i",_ " "' I# 7-+-,-T-r-r I- -,c• -+--,,11--t-->---' I ,i1r'j I I,( b ' ' I I I I I I I I I I I -r~1 I~:---. \ \ I 1 I l.dl,,,.. ~,l.._ _,.::;.-;;;, > I- ¾,_

IQ" ...1 L f- I I I I\\) I 1'' I I L....,..-~~T_L_L7-+-r:::~-L-1-4-L __ .J__1_1--+---+-I-T_L--4,._ ~7-µ_J !\\

,-1-1 1-r-r-+--1---11~ +--1Ll.;\-1-1--IY4~ i , -:::,..,:;-1 I I I I I i 1 I I i i I I i ,-..... i I ' '- n ~ '\.J !. '"~'P" ~ 1-- z ---;;:~

R.ZI E. zz _J_Z3s_1_ '--~a:~! I \11 I ,I'.'.' T_l7rt_L_l::;f£T_l---+-r-1---l-L--1---1--+-l---l-l-----l-t-7- lt1-rl{_ ~ _,.,,• - . 6

I I I i I I I i I.J~ (jjp-f,j,i["l'rr-r-jl tT: 1/ j/1 I I I I I I I I I I I I I I '1. I j\,_ II i ~ ~ ,.,,"' ,:J------' OOmJS z,:::, '

--'-..l.-' , - - _!_1._L - - r_; ~ iiA)L1 11, , ,-..1.-,--,'l,,r-,-l-t---i-.1._L--J -t ,--+->---+-t--'--i--'--t-t--L -il....,-r-- ', Kofg,, ol•

I I T ~ r ; I I I i ,~ 1 I 171[ -:-+ I :74 ~/)' I I I I I .:. L I I I I I I I I I I I I L. I\\__I Kl " I II '~'4"=r>"';s;, ,,.J&7 "',~ w~.J_l '11 :::, 0 1\- Sent"n·' TO PIIC~

--1--+-, --,.-L--l _ _j__t--.L I I II I/ --1- -r, .. 't-,-,-t-r,-, I 7 T ,7 + I T I l i I r I 1v I I '.\ ~' """ ;,_~ '\\ 0 u I 11-•on

1 1 1 1 I' 1 1 1 1 1 1 ~ 1-::., , 1 1 1 n , .L....J_1 ..J._~ 1 1 1 I I I 1 1 1 1 1 , n nurcu~r: ?""" """i ~ \11',. To. u-

T.15 s. -1-7-,-r " ,--:,-1;;_---1tho-lT- J I VJ / ,fl I I rL I I 1 Signal_.,, I ~ 7 r c--, u = .. ,, ..

i i i i ~ i, i --o· es,, / I rJ 4_.__ ---t--r Butte - ,c ,o

-7T t=J~: I r, \ [\ co-J'~· LJ-,_ (jj ·;p-- n A..UN'A ; ·' ,/' I_ I J_ I_, I I 'i~' 11 k,,;i ,,.. -~,,t ~ ~ I} 1' .~ I- L S~On"l_ix 1 f"'~

,__=t_/-i L:-=,+ YUMA I'-.\ f2J;C/ I.A: AAlli , A /1 11 }_[ 1_i _ _l__1 1_;_j~ l Growlere~,"' r:!:'.==::::.- _,..__ Aztec ·-.h•r

· JP, ·.,. oounc -- ... 1 1 -t 1 1 r 7 I *,- ¢ii' .1

I NOIAN ~ or'- f ;,"" MUGGONS I , LL I I I 1 1..,,, Tyson ~ll!!!l""'f' orto, rr A //1

-1-- .. ~~ rwr J LIA,GUNA ---r-- - 7-+-1

·'\., RE s. ~~ ~ I MT s. '/ MIT~-_/ --'-~-:_.)._, J._1_J. L -""" _.,,.;;;;;i;-UJJl_J,Vl~ ~=- /)-. .s:, "1~ 11Aztec

~tnK~ob '· • __ t; lfr...:.L"::l~ • ' ' T r I I I I r I I Ir _1r-,, r.t= -~ ,,~ C' k,,e,"'o0"' " H, Is •<I I I "'"\o Arn7 ,.;"\., I I MIi ,., i 1 1 1 1 -I-;::- ,,,, 1 , / r

T.1& s. i<s. ,.,, "- s•,. ,c, ~ -~r----, it= e== ~)- l -~:-+, lC/4~. u D ~-roe;; ' . lh -;- ,RtodSiu111 _i.,., Fall[/ - _I,' ' -,-' IZ"o{I,, 6¢~Sto ol ~-i-- -~-~-l..J_ .!L_J._;._ ~-L11

ToUlfl . .1 ,~ I. U/, 1 ome ..,.., --·~ lat a pr.mg /\'- i., 1 ~ 11 , , , l<1

0, , 1

A':i'9lw• .Ill,, '<:3. 1- > ~ =rr ·w.11--:,u11P1N& \S\ ~ I c,•'r-lPeak .__,__. i>"' I "" 1 , I ' " .l_L_: _ _l_-+-,---1---1--L+-J

CALI . I no '.Q.Q .:, II ' r~ 1-<=: P<~#f~~- .Ii\"' E,_ ,;,, -·',I+--...:::::,. /II ~ ~ ', ., -; di ,m I\ II +-~-:-J-~_I ::1!-u_;_~_J_1_J 8

--r'.l_ --.;,; ~ - ~ ' ltisdeii{o \i""l~\, ~ - " " CllNA I/ s • ,11Mohowk \ '~ ~,'~ff'0 11 ' I I I I [=>·-, I I l) MEXICO /JA'v'J "' , -d·•· ·~ 1 , ,r-t- - ,\,; .,., . , , , __ embrke ;-if- _,...- l'I ,-r-1--t-r-,>1Q:T-,---i- - 1

-11 ,. .. illets f\l, ¾;[_J_JJ•u11P1#6 ~ 1,·"-.,-, <+--f"'- + lr.w 1·kJ '- M11,..,.... i;._/ ., Colfr,,lrl \ n 111 ".rJ .l_L...J_.1_1-1 __ L...1_~~-J

,.. P<A#Tr" Forton:>1~ I I ,---...---...-...- 'I!! tr 1//1 !,• -~ - Ko phs ,_ ' II 'R ~ !! I I I I I I <II I I

K/J. f lvol n i,.,;: t-- ~ ~ ·, I'_\ .. , ',gurto"""---0, ~ b<"' 'w llto T ,-'--1--M'll I -- ..:.J_-1,_L__J _J

r-1' .I - 1 T"- ,·, .q 'i"> rr ,- e ,,, en ii , .__ , 1 , , ··..; 11 I

2

_ ••.. ,. t '+f m Ar.ob~/ ! \J ~ YI¾, _[_ I I 7 i1 $ ",- :111~, 1 Dl"'i1 ,, As1:!;~ ~pr ~·~ ··--- 0 , ~ ~ ',;'rs-~ " J~_ttj_ I~~ Gar iool'\, \I o, I t'

•••• ,1. I/ ' Y I \ 11 -,,,._-,.,,.,,1.s;;r _ • ii ,,._ "" ~~ _ oks I JV •. \~ b 1 , t 11"'ell , "' = 'cj Eagle Tonk

/ t V ['7 I PLANT~- .a ..-, 1.., '\: -:::i,,.. ~V "\"+-1---l-- ~- Y

l1 ' ,. I ~ \__[__ -+-- ~-1- T-;----;-, tt'.;Z~"".f:',f;\ - ~- Bk "~._ 111 '1- '• I i L -~ ,JI 1 ~ 9

I/ \ , t- -+ - ,---'-f-'f O e -7T -,•-1--t- I I "'

I -... / ..r ~ ·~ 1 J ~ i I I I / I'. 'I;, I Tonks 'j\_~ '\ I\. 1 _".} L _J I _ I 7 t\~ rs:-. I f '" \1 T , -t-o, , 1~ I~ 1 i 1'- \." 7 1 ,, 1 ,.T 1 : L q 11:--- J ,_."'F, I ,

v ''' om~t,ton c, • ·-1..-- ___ ,-. ----1----,._ 11 1 -~-1-<--L "' ·;, , ,.,.,, r ~i,;

C) h: ' T I I 1"- 1 I I ' I I wnL TciN r,,,, 1 1 I I I I \ 1 I I I I I I I I 1 1 I ~ 1 1 I '! I _J 1 ~ I I L, ~ Hit;,,'\, ·,G> I f>_.s,1 .L I I I

'"t" \ ! .. ~ ..l-t-----,.L-+-T-11-- -1-,-rc:~--7~~-L--+-r-'--t--Y--l-7--l-----t--i--t--i-----1-r-'*-+--r~-r ,-1-+ -1--t- )f Wll ~- ---..-r.. 7 ...-, -,-r, ~.....,

t I I i I i 1 I I ,H,,_L;' I i~~1 I I i ' I 1 , I i I i I I I i i I~~' I I ~J.. ' I i IL e -.: ·- r-.,~.,.. i ~~

~ ;s Godscen L.J (" l ~~T-f---'--?-;-1--t-'t--~ 1- 1 -r----j-+-1 ,.1-_:'1,--1-T-1-- 7 -L-r.,'--l- 1 --1-_L-,.-~--J-T-i-..l-1---1-Ji-"t-,-;-1~J-1-1 Ti-rfr I I\. 1 ~i---F-¥-,.-~-t

~ ffOJEC ·- I ,t' I I l I I I I ~ I~ I I I I t,.. I 1 I I I 1 I I I I! ..!~,,J_ I ~~ 1 I I liJ .,_ I .::::i:.9 I I I

or~ r-"r, _ .. v ' T_C_J_"t_r-j1--L-,-i-/,-.l.-r_j_,..1.w_,_ .. -t:__j_r7-+-~-r--_J--1-_, _ _,__L.,._L--+-f--7--i---ll-1-"r~-r7".;t-7-T-11, I ( --t- - ('>-'\,,,! 7 , O

., "'. p 1

1 j_ L ,ti I I 1 1 1

I 1 1"~' I I I I I I I I I I I I I I l I 11 I -.l "-1 .j. 4 __J -t _J/L--1 '"' _J I I l~,iJ

-. t i::> I ' .l-r,.-I-~- - -1---,-L-L---!-.l-t- ----~k,7---r0c,--t---J-r7-r-T--J-r7- --7,-t--l- -s. -r.,.- -'I I I 1-,,-, r\_J1-C) I 101 I 1 I I: I 1 I:!! I I I l\_1 I 14.lul I I I I I 1 1 \ 1 I I 1_1_ 1_i~J...-!__~~--l--l-1~+-I_ _l_.i,.-1_

1::) ,.. ,= -1_ -+----,.-L--l-+-,--l-1-..,_-1_L.J-+-_,_-1-___J_.J.-1':7-L-,,_- _1_ _______ 7

_L7

____ , _ _1 _ _1, r 1-----J P~~--t'lt1

t-, 1

~ T 1 1

+-7

1 I .,. I l I I I I I 1 1 I ,1 I I I \\ I I I I I 1 t I T I I I I I I 1 I I 1--::,:.,1._ \\ I t I

I,_ I I

ll I r--.1.) ~.24"1· ,._z3w .Z2W .z,w'. +--'-~-+--1--J-.!..-L...1._.__, _ _j_L..J_L_'L-1.-L__J_~ _ __j_i_1._,_,l _ _L_L..l-L_L_J _ _[__L_.__J_jf-,--r-1-,-,-;--}',j!--i-T-,-t- '+- I I f--+-i---r-r7 -----

,1,1; "l"t ,., 1 I l. : I .. _ I I l.1_L_l _ __j_J_L_1_.-1-J,,_,!-._LTI _L__l_~_J___I_ ~~+-~7'-L7 ,

... ' '-.-7-70~,-I II I 1 I I I I I 1-=~~ I I I I I I I ~,1 1 1

IION.ZO ~ 1 -i-1-+_L<!.!_~, U _ _[___J_.-1-_L..l._L_j_L_J_'¾_J_L_l_.j.._L...L_-1-lL__.._L_l_,L__J I 20:, l I T I I ~ I

~~ . T.11 s.

~~~.,_ t-iT--1--:-i .JV' ' -......,_ I -r - , --l- l -r 7

'"·~'- -!--L-!-~~-J I I I 1 ! I

'-J •• ~ ~r-1-+-,-r--J 4 I I I I I I

I~ -t-7 - 1 ----1 l\,f.,. QI\/ 1 I I I

._ Jc ;•i~:,i -;- -L-1-L..1-l C I I I I I

0 --..._ -r--1-L-1--l--j

·-:;;:: +-:- .:...-{-~_J ..._ I I I

J

L r 0 5 10

SCALE OF MILES

~~ I

UNITEO STATES OEPARTMENT OF THE INTERIOR

BUREAU OF RECLAMATION

~

~ I~ t t

GILA PROJECT ARIZONA

GENERAL MAP

N7 '

I I I I I I I I I I I I I I I I

I I I I

I

(I) n ~ "' !;\ ... "' "' -<

I I I I < ~; ~ 0 "' z 0 0 c:. ;. f'" ':'

"'\

§

% ~

"' I I I I I I I I I I I I I I

0 I

§

§

§

I I I I I I I I I I I

I I I I I

N ..

I I I I I

'-- ........

N ..

N

"'

"--- - ---- ------ ----------' I OUTLET CHANNEL··.----I I I I

: gi~L.o;rcONTROL. STRUCTURE~ I

STA. l2+3Q _ ___________ _

CUL.VERT NOER 0/l(E ',, ~

PROTECTIVE DIKE STA.33+24.71 • CANAL STA. 30+00

N .. ~

~ C

{-DIKE 240'RT_-·---------------

STA 42+85

,, __ , ~

STA. 36+86 . .§f!_4 _-_-_-_-_---~ca,.-+--+---.--H fl--+-------f----------+------\ TIMBER HWY. BR/OGE o

a

i

"°' STA. 1017+40.9 ~TIMBt°R HWY. BRIOGE

N

1050 STA--:1050+59.63 . -< TURNOUT M ·19.9 L.T."

ROAO CROSSING RAMP -oo \_STA. J7+31.98 j ____ _

STA. 60+00 ( OIKE 240'RT. -­

N N

STA.80+00 { DIKE- 490'RT."-

N

"' STA. 117+60 ( DIKE l90'RT_---

STA.137+40 - fli1i<i(i9o'Rt. __ _

~ STA. 175+00 { DIKE 58D'RT_---

L.AT. TURNOUT:lM 0.7 L.T.

--<fLAif~b~~-::-,.fiT. o

'"

100 .. STA. 116+24.21

~-- L.AT. TURNout M-l.z LT.

~,, STA.116+76.00 = CHECK

150

--<_ STA. 169+26.3 ______ ;;; L.AT. TURNOUT M 3.Z L.T.

i;i

00

-<--- STA.221+49.67 ____ _ r_uRNOUT M 4.Z L.T . "' I. " STA. 248+71.23

/"C.AT.TURNciut·M-4.7 t.T_

I I I I I I I I I I

I I I I I I I I I I

"' UI

"' ..

_STA. 245•00_ j/ STA. 249+0i.D5 p,e'fo,;_,K'°'E~/905 R"T"".~"-'-1e-\\ll;[.--=---T1MBER HWY. BR/OGE ----+----l-----,1-----ll-----~

N

"

N .,

STA. 4+40 ~, I -~!:i~~o·,.oo ROAO CROSSING RAMP -- I

R.17W, R, 18 W,

~ _ STA.274+8D ________ _ :::; ' STA. 274 +50.00 CD

•SIPHON SPIL.L.WAY --­A WASTEWAY

I '-" I N I

I

\

{ DIKE 180' RT. STA.285+6D

...,_ ___ STA 1 2so+~0.61 __ _ I I I I

( DIKE 710'RT. ---

I \ \ I I

\ \

\ \

500 TURNOUT M I.I L.T.

STA. 310+00 • I[ DIKE 200 RT_---•

I I I

\ I

\ \ \ I

\ \

\ I

..

I

.. -c- --lf+:~~~~ih:. i:hT. "

I I I I

STA. 344+6?- _____ ••• ( DIKE 170 RT.

I I I

\ \

\ \

\

STA. 4111+00 ii: DIKE 200' RT. - • 1

STA. 449+97.82 _______ _ :L.AT. TURNOUT M I.S L.T. 1

,s;if{:l8ssili~-\ "' ' )

iii l> CJ> ::r -,

" iii .., ;:; ..,

I I I I I I I I I

I I I I I I ~ I I I

\ \ ,,'-----"'-"'"'-'~==,----~..,..:41a__L!J

\ \

\ \ \ \ \

\ \

\ \

\ \

\ \

STA. 480 113.311 ____ -~ L.AT. TUjNOUT M 9./ L. •

STA. 516+59.45 L.AT. TURNOU_~ M 9.IL.T.

STA! 530 +49.56 TURNOUT M /0,0 L. T, •

\ \

\ I \ _STA. 549+80

1__ __ __ \

, { DIKE 1140 RT. \ \ " \ \ STA. 578+60 \

N N

N

"'

N ..

N

"'

Iii

;i: 0 C z -< ~

Cl>

\ -, -DiKEI 1100' RT. \

\ .__ ___ iL~J~t;.9-1/ko rr:_J_, ~H1+-111-------¼---\-------+---'+---.t?

STA. 1097+60.87 / L.AT. TURNOUT-M ZO.B L. T.

,I-' I -STA.1121 +00.00 "'

/ SIPHON SPIL.L.WAY It- WASTEWAY

)I STA. 1122+00.ob .,..-- CHECK - - - -

\ \

\ \

\ " \

" ,.

UI

" ... n

\

\ \

\ \

\

' \ \ I

\ \ \

STA.1281+74.40" (At.·ru-lfNOUTM 24.:J"i.'t.

' ' ' \ \

\ \

\ \

0

=

.. STA. 1406+22.25

\

]II

N

-;ru:n:r.

..

\ \

SIPHON ______ -

\ \ \

\ \

\

\~

\ \

County Rood

0

\ \

\ \ \

\ \ \

\

STA. 1524+00.00 • z.-.;-:tii1PWout· ;;,-

t-!ft:'tt~~~:.,- t.i u:--"' N

!60

"' z 350 0 -.. .. > 340 .. ...I

330

57

/I\. ,, \ -; -- - -~..-

50

C·; ----Borrow as directed ·-r· for embankment--;,,--, ( 335 '\

;/ (_,,.-,_\ \ ::)\ '\.::,,, \ \:J 'i ', ... j

33()_,/)

i ~~ _,,,.. ....

_,,,,, ... I/

/

,,/ ,

N.G.S ·'_;.

- l

-S• 0005 , ,· ,- -s.G.af Outlet, Channel

' I '

OUTLET CHANNEL - STATIONS

345

£,.~- --- .............

PLAN

MIO O 100

SCALE OF FEET

wmM;, ..... C,.,'M;,~

~:: SECTION B-B

: El 345.0 Min.

:<· · -- -: -- ----30'Min. · --------- --.;

~\\ t 11@).I\\

--- • Natural ground surface

____ .,...

-

~

~

u

PROFILE

-El. 351.0' ~----- -20'/llin.-- -t----1

~ g, "'' .. , "" I .:;, ,., 0 .. , ... , ... , .;!, ::,,

~

:

I I ~ i--

o' -o, ~· ~. "" ... l,

("-EL.334.0

I

~ f 1,,., ~..,,, '""(:- (N.G.S.

SECTION D-D

-~ ' "'-

,,. ...,_,:-:: N.G.S··. :

~-z,-:-------------4-----------~\1-- ,,/ ·• ___ Embankment as directed ~ ' ---------~

~ _,.~ ,N.G.S

SECTION C-C ' .... ' - - - -100' ~~~ :: :: _-_-:: ::;;

0~ in. _____________ _ j

SECTION A-A

0 ,o SCALE OF FEET

60

,o I

10 I

SCALE OF FEET

20 I ·r

"' ,.,. '"' ll!I , ,,. ~::

;1~ - -.,,. i\ .. , .. / ... , .. .,,,..

./ V -..... I , -·S•0.00 I

--

PROTECTIVE DIKE NO. I- STATIONS

..... r'-.

" ;::: t ... ..,-.., ~,-~:~ <;l~ ~;~ ..,, "tlj cti C,

I'->

I I

-- 34

P.C. STA. 32+03.84 P. I. STA. 33+24.71 P. T. STA. !I+ 19.70 A= 13°47', T=/20.87' R• 1000' L •240.57'

360

350

340

330

NOTE

FIGURE 3 REPORT HYO. 359

\

For Typical Canal and Dike Sections,seeOwg.50·0-2614

UNITED STATES DEPtARTMENT OF THE INTERIOR

BUREAU 0FR£CLAIIIATION

GILA PROJECT-ARIZONA WELLTON-MOHAWK DIVISION

~~ I MOHAWK PROTECTIVE DIKE No- I -STA.O+OOT033+24.71 ~.:, AND OUTLET CHANNEL ~" t PROFILE-TOPOGRAPHY-SECTIONS

! .:, :,:

~

~=~::.-~~~-:~=:::--·--·----:~:=~,~==~£:.~~~£~":e-~::::::::~~--~-:~:~. CH£CK£Df'A//....:'~a----AP~OV£_0---'!--~:.:J~f!'l£:'r.

1

OlfNVl!IO. COL.,,.ADO. DEC./6,I/H, I 50•0•2664

er-k 1½:1 ,<-c\

El. 345.0'>, -~

•' "o o

. ~ 't

El. 353.0•,'.,

'" f ~----J

v =.0141 x•-------~----~~

DETAIL A

---b-b~--~ 0 ...

"' ~ 'S .. ... .. .; <.> ·;: 't E 1,....-'1.....;t.--......j.---'=l-----;:;....4-~,'-lll~..IJL....-I ~ b tn e

PLAN

r--24'-of-->t<-- 2s'-011 -->t<·1s'-61~----- 36'-o"----->-:<-- --- 31'--1f-- --~

El. 353.00--~---------._Js~~ 1 ! . l ! ! r ___ : ' ,·'1i' I : i El. 345.00 ··: : i

-~ :~ i : : : 1

. ,:

El. 334.00,/

SECTION A-A

DETAIL B

FIGURE 4 REPORT -HYO. 359

SECTION C-C

'" R .-, ,-·N. G. S. / El. 345.0

SECTION D-D

,,--El. 353. 0

SECTION E-E

' . re-·••·• 19'•0'!. .•••• >t<•• •" • •• • •••• 70'• 0 11 •••••• • •• •••••r•·. • • •••• 70'· o·••••••••>t< •••••It• OM•••-~ ~-~, , ou~-~ ,,_, .. _,_=:~ = --- :--=-: • "'<:ii '"•2:1 I ·0, -~ ,.... N.G.S. / ""-= I - I ' ...... ~

ELEVATION B-B

WE LL TON- MOHAWK OIVISION MOHAWK PROTECTIVE DIKE NO. I-STA. O+ 00

OUTLET CONTROL STRUCTURE GENERAL PLAN AND SECTIONS

(PRELIMINARY)

L A

Br>- -------~--lTI ,------- -- : : I ,.,1

.: : -c:R 1 ,. I :

~ I ' ' I • ' I ao : I __ t_ _____ _

f· ... _, ~

•' .? ...

.r···

.? .., ,.

~

., ------------T

Structure symmetrical :

er>-

------------- - _, --------

about t ··-, j : -------'\- . ._ ___ .;.:t:: ..I :.fill.

... _, ~

~ ':--t- -----:i------- ------------- ------- --

: : &ct) I "I

~ I .: ~ 1-~ l -c:ll -! L__ C , I -;-: I I

I I ! .L . .___________________ --~

.~Sta. l•IB.68 ;..,·· . ' I

B~

PLAN 10 15 10

SCALE OF FEET

l!S

I I :-c,,-------- -----ff 3s3:o Min:;--· --- --- ------,207'-5f

-- -------________ -H--1---------

..Jo

' I

Sta. 3•26.//--.,~

--- ----- ----- ------ ------- --- -~- ---- -- ------- -- ------ --+i ' .

I

' ;-------1s'-1'--~~--~~~--~~~~~;;._-~~--~~~~--~;~;~~----------·-;i,--~-{p------20·-o·-------·*· -- -- - - --23' 6" - -- --- --->1< ---- - -- ,s· 2· --- - ___ ,.:..,. -- --- - --- -- - -- - -- -- ----- 92'-5f ---- - ·-. - - ---- -- - ---- - -- --- - __ ..,..i ' ' '

I I I I I •••

' ,, ~ I I I f/ 3440~ .I --· ._.•:•·./ ' : ;._c; . _-:_,_; ..... I I

: I . {End of compaction

1Compocted backfill

J A

'

~ 'z, ., ., ~ ' ~~ .-······--... ~fl i

ii \ \ / --........ \

+-­! -<?'' l~ \

8~ \ i;C , ~? ( ;;;ol, / .... ~ ... ______ ':t?- / .. ·

Sto. ,.,s.~-r---rr ·-..... ··---~-<fl-··---

446- ••.

····{ of Dispersion ··-------:-1 1~ ---Chonnel :<,.-· / I 24"Min. r1prop-P\_ . .- ·

r---------125'-o"--------- I -<3:,

2:1 -

FIGURE 5 REPORT HYD. · 359

LOCATION PLAN

10 0 u.J

40 1

80 1

SCALE OF FEET

1ri

cv" ----Bockfil 1----··

';<-I0~0"Min:-->j ·-···i>-_~~~-·

SECTION D-D

.s ~ .... "'

. ', !·'

, ____ \-9"Min. compoc!ed Tl ~ ~:-1 ,

· " • : r, rt s · : subbose 1f directed , . • . , ,. . ,.; :-t'·12 Mm. ~!~~---/f!!Q~ · -- - - · ------ - - -· - - --Culvert Section Type ''8" · - - --- -- · -- -- -· -- - - -- ----- --- -~- _ <;yfr_e.r!. -5/.fJ!o_n_ - - - - ~- - <;y[v_e!!_ ?..e_cJ!o_n ____ ~ ' 0 ~

El.332.0-·-

-: f->B'Min. , 1

, Type "A : _ , 1., , 1., : Type q • ! Type, D. : , • ; ""s _, ___ --· -------28-92 ---·- ---- ------>K-- - -· -- -- - ---- - - - --- -- - -- - - - -- ---3 Units@ 20-02 • 60-12 ----·- - -- --·- -- - -------------- - -/8-1--- - ____ ,...,., ___ ---- -/B-0 --·-··-->t<- -- · · - -----22-6 -- - -- --- -->' @6,0 •

'60'0·.

I ~----8 • /,, ~ •• {:-, ockf1/l--·-t..·) Jt:_,, I '-~

F------------1 I I I

.• -Symm obout E

SECTION

0 ~ ~

"'

B-B

SECTION

I 0 5 10

SCALE OF FEET

A-A

k--·Symm. about E ~ r<--24"Min. · ---9'-o"Min.-----=4

' ' ' Compacted :-.•-..-; ',.;~- ·· .•. _ ... ;,:.

bockfill-. __ .:;;:%------·-3"Fillets-:,.

-~ ~t!~~;:&M t>> ' . :,:j;.z: \ 'I

9• Mm compacted ./

subbose if directed· SECTION C - C

,~

.,._

~~l ii ~'--~ ,-5'Min .

:---' _ .. [/, 306.04

""-,.,,~co-,,;~;,:-;; ·{;ckfi/1 .. ~:>! t<-12u Min.

. .,.

,·N.G.5. ESTIMATED QUANTITIES Concrete in inlet tronsition ond outlet structure. ____ 245 Cu. Yds. Concrete in culvert sections _______________________ /70 Cu.Yds. Reinforcement steel. ___ ... _____ .. _______ --- __ 57,000 Lbs. "' ... :~

~'GI

NOTE EXTERNAL DESIGN LOAD FOR CULVERT SECTIONS

SECTION TYPE LBS. PER SQ, FT,

A 890 B 1800 C /690 D 660

REFERENCE DRAWINGS INLET TRANSITION AND CULVERT BOX ....... /JO·D-2678 OUTLET STRUCTURE. ______ •• _______________ 50-0- 2679

UNITED STATES DEPARTMENT OF THE INTERIOR

BUREAU OF RECLAMATION GILA PROJECT-ARIZONA

WELLTON-MOHAWK DIVISION

MOHAWK PROTECTIVE DIKE No. I STA.12+3O

CULVERT UNDER DIKE GENERAL PLAN AND SECTIONS

~ ::::::~~ :::?:~:~;":~::::::~::_~{; j;f ti~:~:::~~~-:-:-~:::·:-: ii! DENVER, CDLORA00-0EC.Z7, 1949 50-0-2677

Channel as directed-\

-<: A ·~j 1 ~--~ 7 Spaces @4~6~31-61-<-

! ! : --, I

I I

I I\ I

' I ', I

'··},-Riprop.

/L JG ~-~v

~

~

"' ~ .. ,,,-----~ '

-. ' '

-,

CANAL FLOW ·>

',,J £ Wellt;;,,-Mohowlt Canal.,:'

_,, ... --

,,--,-'

' .,

' ' ' '

Slope as directed !415' Min

-c::; El.286,8----_L:,.;:.-~

;.1 V .-3:I

-----7 I

J/}' -:-··--------- Slope as directed / / '··E!.286.8 ---- -

f5'Mjn • ' ' ' L_

... .... _ .......

~ --

.--3'/'

~ _, !!?

_31____ -----------1r,---- ~------fjl '·We//ton-Mohowk Canal ---- V ---- - ·----36-0 ---- • f Sta. 938+00 L// ~ 11=!====!-==f:::"I' r-.

-;.i

~', _, ' ~ \

' '

'

i ..t "' "q,

\ ,,1,.I \ ""!."" '

..;,.f -----, - '

/I I

' ' ' ' z77---...__ A I\ A A I\ r, I\ I\ ,-11 ' A A I\

I',, ; ._, l--3d ~ti ' '

' .. ' ', ... ~ \ ~, .. _)

("Bank as directed ~ ....... ___ (: .. _-::...

Extend riprop _ .. ---------­as directed---..,_

',. -~ /·' ........... , / ......... ,.. .,,,.,,,. --- ---r:::~~-----~

~ as directed -------·

.jA ,---Diversion dikes

:' os directed.----------. l ~

PLAN Note, Opposite sides symmetncal

except as shown.

,~ ....... ~ '? 2p :ip 4P SCALE OF FEET

:' ,/

Bonk as direct~d. ____ ::2__:,

----"'----Parallel drain

os directed

~ ~

'<,-6"

/ ~ ,'V'

- 11~~),/ ', _,,,.,.

<..>d'

~ ~ ~ .....

.'P ~ ~ ....

J.: __ y _____ Ji __ _ ' .., 1 r------i--(rj I I (ti

: : 13 ;e I I ! I I ' I I : ,.I I~

' ~ I I I .., I 0, I 'O

~

-t--~-~:-_ ·. I ~ ~

,.J.. ~ ..... 0 ~ ~ ~ ; ~ ~ -t---,::_--_.

,, ..... ~

SECTION B-8

~ -~ I"' lf I ~ : ~ ~ ti! " ;} , Embankment ··--24• Min. riprop.

-t+ : \ ' ' ; l : ~ ' .., ' ' ~ _, .... ....

-' ~ : Q

: j ' .. -+-~

? ~

: : a-__ y __ j: __ 1-,C

<,j <ti ,.;

q:

:t: 0

as directed--~. , 't ---

4'Min.--~ "J#1 ~-- ·-N.G.S.

-.... 12· ~"¥---·---compacted backfill

0 l&,I Cl)

SECTION C-C

Embankment as d,rected--i. NGS--

I z• ·•J,''f',•---Compocted backfill

SECTION

ESTIMATED QUANTITIES Concrete in structures _________ ________________________ 4JJ Cu. Yds. Concrete in floor slobs and povinf. ____________ 50 Cu. Yds. Concrete ,n wash outlet, poving, ond baffles _____________ 148 Cu. Yds.

Reinforcement steel ___________ ----------,-------- 106,600 Lbs.

Lumber ------------------------------~--------· 900 F.8.M.

REFERENCE DRAWINGS WASH CHANNEL INLET- WALLS AND PAVING __________________________ 50-D- 2436 CENTER UNIT _______________________________________________________ 50-0- 2472

WASH CHANNEL OU TL£ T-WALLS-PAVIN<i - BAFFLES ... _. _______________ 50-0-247 3

BRIDGE-PLAN-ELEVATION-SECTIONS .. _______________________________ 50-D- 2474

2:1--

Ccompocted embankment where foundation is above excavation line or natural ground surface.

D-D

0 10 I~

SCALE OF FEET

FIGURE 8 REPORT HYD.

Embankment Compacted as directed-., Rock UI.. embankment- ...

N.Gs.. • I. : ~-- I

6'Min.--j ___ ~ _-::- ,- ·. ~ -,.,~--12·-,. ,.;.---·-Compacted

' · bockftfl

SECTION E-E

.. -J'op of bank. L___J

SECTION F-F

'14• Zoned filter.

SECTION G~G

NOTE Timber roiling not shown, for details see Owg. 50-0-2474

UNITED STATES DEPARTMENT OF THE INTERIOR

BURE AU OF RECLAMATION

GILA PROJECT-ARIZONA WELLTON-MOHAWK 0/VISION

WELLTON-MOHAWK CANAL-STA.938+OO

WASH OVERCHUTE GENERAL PLAN AND SECTIONS

DRAWN: ______ ~ft{I_ ___________ SUBMITTED:":~--.Z~~--

TRAC £ D: _____ C~ ."'!·_~._ _________ RECOMMENDED:. __

CHECK ED, .cJ1ti__ .. .. _/1,1.'f.' APPROVED: ___ _

•

l"°"-----1!.&'!.-----t-6° I -------61-0°-----------------~----,

' ' ' ,------i l, V 4 J I

I l

j> ... !

L A

t ,:.: I I

:E ,g ... g a::

I

(~

t

~1 y

:<----1f ---,

~

i I ___ T ......

_j ' ,,.

' \; !,/ ::.i-, DETAIL A

"'"13•1<!-1T I

,---~·' =I ... ;: .... , I • ,.,. j___ ' 7;

·v DETAIL B

--,o.42'1<-_, _I -

f---M--1 } I - / ~ ,,' ' . ,

I ~ I / f ___ l ,,'

k---1.1611--.J ',,,r,.,

DETAIL C

------·· O - 0 ---T 000011 :_\N

ooomm I . -0n0 0 0@ I j ~ 0 u O II .. I A "'

n O :l I I II 8. I I

ooooo~ I ! 0 0 0 T I ! •• 0 D : I ' , Thislroiningwallcorrespondsto'i.ofstructure--, -~ O (l __ 1 I __ ___L

..L.

r--, : I

·' ... . ~

i<,

Check wall----- ~-9"­,-..._,i

'i--

f

._-:.-f';_---Pea Grovel ---~---.:a,,.

'-1.. 'f'

L_I_ I ~ ________ 1

'l.Jm

PLAN

SECTION A-A

., -~

I I ~--------,-::--;-:-:=:-~::::;:;-;,;::;::-----77--T .:

dil.J; ;--Sand leve~!"!>!.~~'!_e~~!f:___ __ ___ _ ~ .! 1----------------------~-------- . ~f -T : ~19 - = : : 10,oe ,--¾" Plywood ' ' ____ _;.

WELLTON~MOHAWK DIVISION

OUTLET CONTROL STRUCTURE

-~ D~

=-c:

~~ =~ __________ ____;__ ______ _J:~ = 1:24 _SCALE MODEL

A. The Model.

C. Discharge of 7000 second-feet.

FIGURE 8 Report Hyd-359

B. Discharge of 2000 second-feet.

D. Scour pattern after discharge of 7000 second­feet for 2½ hours (pro­totype).

WELLTON-MOHAWK OUTLET CONTROL STRUCTURE Operation of the Preliminary Basin

(Outlet channel at Elevation 333. 8 feet) 1 :24 Scale Model

,,Check wall

----f ' ' -..,.

---:J CD

I

-

:'Check wall

) W-I

---~ co

><- - 12'--~ ,6' R. I I I /6'R.

i _x---~ "~,,,,,,,,,,,,,,,~,,~,\v,, I I ~\\\.\\,,~,\~/

I ! l : / / L:r -----._261--- - ---->k- - -1s'-s'!.-->f<- - - -- --- - - 36'-- - -~ - - -- - -:,,, t ... 2: 1 Slope

I I I o I

:..C------ 26'-------~---16'-s•--->+<-- (t --~ I

' ' I

t-2: 1. Slope

A. PRELIMINARY BASIN

/Check wall

---1

---i ..,.

,, x---~~----------------,

_i

.. ,, ~'''''''''"'''\'~~i i : I I /

I I I I,

~----1a•-s·--.-->1<-:.- ,2'-->rC------ 24' ------;,,-i t2:1 Slope

C. BASIN NO. !

/ Check wall !

B. BASIN NO. g

----f CD

---f r--....

.

' ' '

/61 R,

I 1''' '' " ,. ,,, I

' ' ' I I I I

k----19!.5!!--->k-- 12' -->k--12' --~

D. BAS.IN NO. 4 RECOMMENDED

::a "'. ;g .... ::a -WELLTON-MOHAWK DIVISION -t.=

OUTLET CONTROL STRUCTURE == ~ VARIOUS BASINS TESTED !==' ca

1:24 SCALE MODEL c.a ~ =

A. Outlet Channel at elevation of 333. 8 ·reet.

C. Scour pattern with chute blocks removed and channel at elevation of 333. 8 feet.

FIGURE 10 Report Hyd-359

B. Scour pattern with channel at elevation of 333. 8 feet.

D. Chute blocks removed and channel at elevation of 324. 6 feet.

WELLTON-MOHAWK OUTLET CONTROL STRUCTURE Operation of Basin No. 2

Discharge of 7000 second-feet and resulting scour 1:24 Scale Model

A. Scour pattern below Basin No. 2.

B. Basin No. 3.

WELLTON-MOHAWK OUTLET CONTROL STRUCTURE Operation of Basins No. 2 and 3

Discharge of 7000 second-feet and resulting scour (outlet channel at elevation of 324. 6 feet)

1:24 Scale Model

FIGURE 11 Report Hyd-359

A. The Model.

B. Discharge of 7000 second­feet.

FIGURE 12 Report Hyd-359

C. Scour pattern after dis­charge of 7000 second­feet.

WELLTON-MOHAWK OUTLET CONTROL STRUCTURE Operation of Basin No. 4. (Recommended) (outlet channel at Elevation 324. 6 feet)

1 :24 Scale Model

A. Discharge of 7000 second­feet.

Scour pattern after dis -charge of 7000 second­feet.

FIGURE 13 Report Hyd-359

B. Discharge of 20.00 second­feet.

D. Scour pattern upstream from check wall after discharge of 7000 second-feet.

WELLTON-MOHAWK OUTLET CONTROL STRUCTURE Operation of Basin No. 4 (Recommended). (Outlet channel at Elev~tion 333. 8 feet)

1: 24 Scale Model

-~

350

349

348

347

346

l-­~345 IL

z -344 z 0

~343 > w ii:1342

w ~ 341 IL 0:::

~ 340

0::: w !;i 339

3:

338

~3.7

336

. 335 I I

33~0

I

., /:

_,Ji1"'

,.,

~ /

o Using No ... 4. orifice plates

/ ~-i;:i Using No. 2 orl-fice plates ·

-~-

~/ C./

V V

/

L V

./ V

V Note: Water starts to flow over top of ,J

I/ check wall .at·water surface elevation 348.2 feet.

I II"'

2 3 4 5 . 6 '•7

DISCHARGE IN THOUSAND SECOND-FEET·

WELLTON MOHAWK DIVISION

OUTLET CONTROL STRUCTURE HEAD· DISCHARGE CURVE

l:·24 SCALE MODEL

,_,,. ~

.,

a g ,0

··1i:a"'" ,o_ "'·<:\ -tc

. -,a J~r i?·;ji

w VI -----------------------------------------------------------------------------... ·'°

350.0

346.0

~ 342.0 UJ IL.

338.0 z z 334.0 0 1- 330.0 <[ > u..1326.0 .J uJ

322.0

318.0

Ml

- - --- I I I - ......... ,Check wall ,

-e--- )" " ·-. . .. .,_ --

/ ~-- ~ --1 ....... --· r---:::'.'.: ... ..::::.,..~ - .,.

~-- I'''' """ '" ''" ''' ''' ' '"' ~ El. 330. 0 ~~

'" I'"'

--· ~~ ..... -

f .. 1j,

'"" ~,,

Profile along centerline of slot. Pr:ofile along left training wall. Profile along a line 4feetfrom

left training wa II.

~....:.~ ' ---... 5-..,

' '-~ ,-=: ~ ~,r

. ~

I'~ ,.Bottom of outlet

' \ channel at El. 324.6 '"' 'l ~

'"' ¾ '"'I'

- I 2 -8 -4 0 4 8 I 2 16 2 0 24 28 32 36 40 44 48 52 56 60 64 68 72 76 80

DISTANCE FROM CHECK WALL IN FEET

WELLTON-MOHAWK 01 VISION

OUTLET CONTROL STRUCTURE RECOMMENDED DESIGN

WATER SURFACE PROF.ILES WITH BOTTOM OF OUTLET CHANNEL A_T ELEVATION 324.6'

I: 24 SCALE MODEL

"' m .,, O::!! ,O(i) -IC

"' :cm -< g-. m

w "' •

350.0

346.0

.... UJ 342.0 UJ

lL 338.0 z z 334.0 0 ..,_ 330.0 ~ > UJ .326.0 J w

322.0

318.0

.........

..e:--

-

I:::' "''' ,,,

'""

, Check wall I

I

' ~

" ~ -~ - - -~ -,.,, ,,,, I''' '"'

---

~

--

El. 330.0 ·, ..

\ l '\" ~ t ,.__

' """' "'"' r\.~

Profile along centerline of slot. Profile along a line 4 feet from

left training wa 11.

-~ --~ /

Jj rBottom of outlet channe I

~\ ' at Elevation 333. a ,,,~ ~

'"' ~ I\~

~ '~

~

-12 -8 -4 o 4- 8 12 16 20 24 28 32 36 40 44 48 s2 56 60 64 68 12 76 80

DISTANCE FROM CHECK WALL IN FEET

WELL TON-M.OHAWK DIVISION

OUTLET CONTROL STRUCTURE RECOMMENDED DESIGN

WATER SURFACE PROFILES WITH BOTTOM OF OUTLET CHANNEL AT ELEVATION 333. 81

t:24 SCALE MODEL

" m .,, 0-n

~:c~ -< 0-...... ,~ .~

PART ll--CULVERT UNDER DIKE

Introduction

In conjunction with the outlet control structure, the culvert under dike is designed to control the evacuation of storm run-off waters retained.by Protective I>ike No. 1, Figures 2 and 3. The culvert under dike is located approximately 22 miles east of Yuma, Arizona, -and about 1/2 mile south of Wellton-Mohawk Pumping Plant No. 3, Figure 2. · ·

The structure, Figures 5 and 18, consists of a culvert which passes under Protective Dike No. 1, a horizontal section or stilling basin at the downstream end of the culvert, and a 2: 1 baffled apron which drops the flow from the stilling basin to the outlet chaI1.D.el. The structure is designed for a discharge of 1, 250 second feet, at a head of 15 feet above the culvert invert.

Model studies of the culvert under dike were made to insure that its capacity was limited to 1, 250 second feet for an approximate head of 15 feet, and that the fl.ow would enter the outlet channel with a minimum of scour. · ·

The 1: 12 Scale Model

The model, which was built to a geometrical scale of 1: 12, Figure 19~ consisted of a head box, 8 feet long and 10 feet wide, rep­resenting the reservoir upstream from the culvert; a tail box, 10 feet 1-ong and_ 6 feet wide, containing the outlet structure and a portion of the outlet channel; and the culvert joining the head and tail boxes. · The head and tail boxes were constructed oi wood and lined with galvanized sheet metal while the culvert was fabricated from transparent plastic to permit observation of the fl.ow through the structure. Three-fourth­inch plywood, impregnated with linseed oil, was used to construct the stilling basin, 2: 1 apron, and training walls, while the baffle piers were made of redwood.

Water for the model was supplied by a portable vertical tur­bine pump and metered through a combination venturi and orifice meter. Since no data were available on the channel downstream from the culvert, the model was operated with the channel at several elevations represent­ing different degrees of degradation. Flashboards were used as a fl.ow control anp to hold the sand, used to represent the channel, in the tail box at the desired elevation.

9

The Investig~tion

General

Eleven different stilling basin designs were tested in the model, ~igure 20. These designs varied either in length ~d width of basin or in the elevation_ of the upstream end of the· 2: 1 apron. In addition, several different baffle pier arrangements, consisting of combinations of rows of baffle piers shown in Figure 21, were tested in each of the stilling basin designs. In the following discussion, the various designs are referred to as Designs 1, lA, 2A, 4EF, etc. The numeral refers to the stilling basin design shown in Figure 20 and the letter (s) denotes the rows of baffle piers, Figure 21, installed in the stilling basin.

Design requirements for the culvert under dike were: ( 1) the maximum discharge should be l, 25Q second. feet for a head of approx­imately 15 feet above the invert of the Cl:llvert, and (2) the scour in the outlet ·channel immediately downstream from the structure should be nominal. Normally, if the former condition was not satisfied, the model arrangement was modified by changing the size, number, or location of the baffle piers in the basin until the head approximated 15 feet .. Larger or additional baffle piers in the basin increased the head required to pass 1, 250 second feet, while the head was decreased when the size or number of baffle piers was reduced.

The hydraulic efficiency of the various basin designs was determined primarily from the appearance of the flow through the structure, and from the amount of scour in the outlet channel. The scour pattern was obtained by operating the model at the maximum dis­charge of 1, ~50 second feet for 1/2 hour which is equivalent to approx­imately 1-3/ 4 hours in the prototype.

Design· 1 {Preliminary)

The model was initially constructed as shown in Figures 5 and 18 except that Stilling Basin 1 (Preliminary), Figure 20, was installed at the downstream end of the culvert.

In general, the operation of the pre_liminary design was unsat­isfactory. Under a head of 15 feet, the culvert passed only 1, 190 second f~~t. while about 17. 5 feet of head was required to pass the maximum discharge of 1, 250 second feet. The culvert flowed full from the en­trance to the upstream end of the transition section, and partially full throughout the transition, Figure 22A. Upon leaving the transition section, the flow was concentrated- along the training walls and, after striking the first row of baffle piers on the 2: 1 apron, the flow sprung free and fell into the channel at the lower end of the 2: 1 apron, Figure 22B. Results of the scour test for the maximum discharge of 1, 250 second feet are shown in Figure 22B.

10

The capacity of the culvert was insufficient because the culvert did not flow full throught its length. It was found that by manually increasing the discharge above 1, 250 second feet, or by placing an obstruction between the ctilvert and the baffled apron, the transition flowed full and continued to flow full when the obstruction was removed. When the transition was tlowing full,' the head above the culvert invert dropped to 12. 5 feet for a discharge of 1, 250 second feet. The culvert, under these flow conditions. acted as a draft tube, with negative pressures on the roof'along its entire length. With the increased depth of water flowing from the culvert,· the flow no longer sprang clear of the first row of baffle piers but followed the slope of the apron, resulting in a fairly uniform performance.

Since the culvert .was designed to flow full throughout its length and the headwater dropped to 12. 5 feet when flowing full, a row of baffle piers was placed between the culvert and the 2: 1 apron, Row A, Ftgure 21 ;_j The baffle piers P.ut sufficient back pressure on the culvert, by obstructing the outlet,_1 to cause it to flow full and raised the headwater to 15 feet, the design head. Figure 23A shows the model discharging 1,250 second feet with Row A of baffle piers in place and the resulting scour pattern. The depth of scour using this arrangement was 9. 5 feet as compared to 12. 5 feet observed with the preliminary design.

Scour tests were also run using baffle piers, 4 and 5 feet in height, on the 2: 1 apron. Results of these tests disclosed the depth of scour to be approximately the same as that obtained with the 3 feet high piers. Table Il is a recapitulation of all _the scour tests made on the culvert under dike. Figure 23B shows the model discharging 1,250 second feet and the resulting scour with 5 feet high baffle piers on the 2: 1 apron.

Desisn 2

In Design 2, the length ·of the stilling basin was· increased from 10 to 15 feet, and the stilling basin and apron were widened by diverging the training walls to coincide with the alignment of the transition walls, Figure 20~ For a discharge of 1, 250 second feet, the flow failed to follow the diverging ~alls and caused excessive scour in the outlet . channel,· Figure 24A. To determine the effectiveness of the baffle piers on the 2: 1 apron, a scour test was run with the piers removed from the apron. Figure 24B shows the resulting scour pattern, in which the greatest depth of scour was 16 feet, or 3 to 7 feet deeper than that observed with baffle piers on the apron. Thus, the apron baffle piers

· are effective in reducing the scour in the outlet channel.

To obtain better flow distribution over the 2: 1 apron by forc­ing more flow along the training walls. the baffle piers were concen­trated in the center of the stilling basin, Rows B and c. Figure 21. These arrangements improved the flow distribution, and the depth of scour was ·a and 10 feet, Table ll.

11

Design 3

Since the flow f~iled to follow the diverging training walls in Design 2, the width of the baffled apron in Design 3 was held constant at 30 feet by using parallel training walls, Figure 20. Rows C and D of basin baffle piers, Figure 21, were tested with this design. The parallel training walls confined the flow, and the flow distribution over the baffled apron was fairly uniform. Scour tests with Design 3 gave results similar to those obtained with Design 2, Table II.

Design 4

From the results of the tests on Designs 2 and 3, it was felt that a longer stilling basin was .necessa~y to obtain better flow distribution over the baffled apron. Design 4 consisted of length­ening the stilling basin from 15 to 30 feet and installing parallel training walls along the stilling :basin and baffled apron, Figure 20. To maintain a headwater elevation of 15 feet, various combinations of two and three rows of baffle piers were placed in the stilling basin and tested, Table II. ·

Figure 25A shows the operation of Design 4 at a discharge of 1, 250 second feet with Rows E and F of baffle piers installed. In general, this design gave the best distribution of flow through the structure, and the resulting scour was not excessive.

Design 5

Design 4 required two or three rows of baffle piers in the stilling basin to cause sufficient back pressure on the culvert to main­tain a headwater elevation of 15 feet. For Design 5, Figure 20, the baffled apron was raised 2 feet, making a step at the upstream end of the apron which provided sufficient back pressure to maintain a 15-foot head and eliminated the need for basin'baffle piers. Tests on this design showed a slight concentration of flow in the center of the baffled apron, but the scour was only slightly deeper than that ob­tained with Design 4, Table II. Tests were also run with different baffle-pier . arrangements in the basin.· but the additional baffle piers increased the headwater 0. 2 to 0. 8 foot above 15 feet and slightly in­creased the depth of scour.

The elevation of the outlet channel was lowered 1. 3 feet to elevation 332. 7 feet for the scour tests with Design 5 to Simulate a greater degree of degradation of the channel.

Designs 6 and 7

Designs 6 and 7 were similar to Designs 4 and 5, respee-ti vely, except that the length of stilling basin was r~duced from 30 to 22 •. 5 f e_~.t. and the vertical curve between the :Stilling basin and the. 2: 1

12

apron was removed, Figure 20. Table II gives the results of scour tests on these designs which were tested with various baffle-pier arrangements. In general, the depth of scour was slightly less with the shorter stilling basin.

Design 8

The basin training walls were diverged at the same angle as the culvert transition in Design 8. Also, the baffled apron was extended downstream to permit scour tests with the outlet channel at lower elevations. With the diverging basin, it was necessary to add a row of baffle piers in the stilling basin to obtain a headwater elevation of 15 feet. Scour tests, which were run with the outlet channel at elevations 327. 3 and 319. 2 feet, indicated that the depth of scour increased from 6. 3 to 6. 6 feefwhen the outlet channel was lowered, Table II. Figure 25B shows a discharge of 1, 250 second feet through Design 8 and the resulting scour pattern.

Design.9

Except for a fillet immediately upstream from the baffled apron, Figure 20, Design 9 was the same as Design 8. Tests on this design showed the headwater elevation to be 14. 2 feet without using baffle,piers in the stilling basin. The depth of scour was slightly . greater than that .obtained with _Design 8.

Desi'gns 10· and 11

The baffle piers on the 2: 1 ·apron were moved upstream in Designs 10 and 11, such that the first row of piers was at the 2-foot step, Figure 20. Otherwise, the designs were the same as Designs 8 and 9. The apron baffle piers provided sufficient back pressure on the culv_ert to raise the headwater elevation to 15. 3 feet for a dis­charge of 1, 250 second feet and thus eliminated the need for baffle piers in the stilling basin. ·

Design 10 was operated at discharges· of 600 and 1, 2.50 · second feet with the outlet channel at three elevations: 320. 3, 328. O,_ and 333. 5 feet. In general, the depth of scour increas~d as the outlet channel was lowered, and the depth of scour for the three channel elevations varied from 3. 5 to 4. 8 feet for a discharge of 600 second feet and from 6 to 7. 1 feet for 1, 250 second feet, Table II. The flow through the stilling basin and over the baffled apron was well distrib­uted, Figures 26 and 27.

,I

A fillet was placed upstream from the step in Des_i:gn 11, Figure 20. Although the headwater elevation was lowered slightly for 1, 250 second feet, the depth of scour increased with the fillet installed, Table. II. Therefore, no further testing was done on Design 11.

13

The Recommended Design

From the test results tabulated in Table II, _stilling basin Designs 4., 6., 8., 9., and 10 gave the least depth of scour for similar qischarges and elevations of the outlet channel. With each of these designs., the flow through the stilling basin and over the baffled apron was evenly distributed over the width of the structure. However, to maintain the headwater at an elevation of approximately 15 feet., it was necessary to install auxiliary baffle piers in each of the stilling basins excep·t Design 10. Although all five designs would probably op­erate equally well., the use of auxiliary piers adds to the cost of the. structure and in~reases the possibility of weeds and other debris

. catc~g on t~e bEi.ffle piers. Therefore., Design 10 is recommended for construction in the field.

W~ter-surface Profiles

Profiles of the water surface for discharges of 600 and 1., 250 second feet were observed in the recommended design and are shown in Figure 28. The minimum amount of free board on the training walls is approximately 2 feet at the maximum discharge of 1., 250 second feet.

Piezometric Pressures

Piezometric pressures along the roof of the culvert and on the surface of the apron baffle piers were obtained from the model.

Culvert Pressures

Pressures were observed at 11 points along the roof of the culvert., Figures 29 and 31., for Design 2 and the recommended design. With Design 2, pressures were recorded at the! maximum. discharge of 1., 250 second feet and the following cond_itions of flow., which are tabu­lated in order in Figure 29: ( 1) The head oil the culvert invert was 17. 5 _feet with the transition flowing partly full; (2) The head was 12. 5 feet with the transition flowing full; ( 3) A row of baffle piers (Row A., Figure 21) was ·_placed m the stilling basin to cause the transition to flow full at a head of 15 feet; ( 4) As in ( 3), baffle piers were placed in the stilling basin., and the vortex in the head box was eliminated by placing a piece of plywood., 1/ 4 inch thick., on the water surface over the inlet which reduced the head on the culvert to 14. 5 feet.

· The lowest observed pressure with these arrangements was recorded at Piezometer No. 5 under flow condition (4)., where a piezometric pressure of 9. 5 feet of water below atmospheric pressure was observed, Figure 29.

14

With the recommended design, pressures were recorded for discharges of _ ~00! and 1, 250 second feet under normal flow condi­tions, Figure 29. The lowest observed pressure was near the en­trance to the culvert at Piezometer No. 2 where 8. 6 feet of water below atmospheric was recorded at a discharge of 1,250 second feet.

A close study of the pressures listed in the table, Figure 29, indicates some apparent inconsistencies between Design 2A and the recommended design for a discharge of 1, 250 second feet, espe­cially at Piezometers No. 2 and 5. The pressures in the culvert were difficult to obtain due to air which entered the culvert through the vortex and collected along the culvert roof where the pfezometers were located. Every effort' was taken to remove the air from the piezometer leads prior 1o each observation, and it is believed the pressures tabulated in Figure 41 were as representative of the true pressure as could be obtained under the existing conditions.

Pressure on the Baffle Piers

Piezometric pressures on the upstream and downstream faces of the apron baffle piers were obtained from four test piers-­each fitted with six piezometers--as shown in Figure 30 .. The great­est range of pressures were recorded on Pier A where a maximum pressure of 8. 3 feet of water above atmospheric was observed on the upstream face, and a m~:gm pressure of 0. 2 foot of water below atmospheric was recorded on the downstream face.

15

s

Table II

SUMMARY OF TESTS Using Different Stilling Basin Designs and Baffle-pier Arrangements

Model arrangement : : : : Maxi.Jnum depth Height of: : :Elevation: of scour (ft)

Stilling:Baffle piers:baffle piers:Head on: Dis- :of outlet:At center: Rt or lt Remarks basin: in basin :on 2:1 apron:culvert:charge: channel: of :of center

design :Row :*x (ft): (ft) : (ft) :(cfs) ·: (ft) : channel :of channel: l :None:. - ·: 3 : 17.5 :1,250 : 334.0 : 12.0 : :Open channel flow in transition. No

(Prelim): : : : : : : : : stilling action · l :-A : 7.5 : 3 : 15.0 :12250 : 334.0 : 9.5 : :Transition flows full. Good stilling 1 : A : 7.5 : 5 : 15.0 :11250: 334.0 : 9.0 : : action. Height of piers on apron 1 : A : 7.5 : 4 : 15.0 :1,250: 334.0 : 9.5 : : has little effect on flow or scour

2 : A i ! • 2 : A . 1-5 . 2 : B . 1-5 . 2 : C . 1-5 . 3 : C . 7.5 .

: : D i ! •

4 : E ·: 18.0 D : 27.0

4 : E : 5.0 D . : 30.0

4 : E . 5.0 . : G : 16.0 :· F : JO.O

4 : E . 5.0 . : G : 16.0 : D : JO.O

5 :None: . .

. .

None -1 :i 3

J

3

3

3

3

1,5.0 1~.o 14.8 JA:.2

: .14.5

15.0

: 15.0 . . : 15.0 : . . : 15.0

J 15.0 . .

:1.250 :l~O :l~O :1.250 :1,250

:1.250 :1,250

.o 334.0

:1.,250: 334.0 : :1.,250: 334.0

. . . • :1.,250: 334.0 . . : . . :1.,250: 332.7 . . . .

8. .o

. 6.0 . : 7.8

. . . 7.2 . . . . . . 8.7 . . .

: :

. . : . . . . . . : . .

.E,attern :Flow concentrated in center of structure :Excessive scour in outlet channel

7..Q__tFlow C>y~r apron evenly distributed :Slight concentration in center

10.0 :Slight concentration along training walls

8. 2 : Flow evenly distributed 7.2 :Flow evenlydistributed and nominal . scour . 8.0

. . :

. . :Outlet channel lowered. Good flow . distribution .

-~

Table II--Continued

SUMMARY OF TESTS Using Different Stilling Basin Designs and Baffle-pier Arrangements

Model arrangement : : : : Maximum depth Height of: : :Elevation: of scour (rt)

Stilling:Baffle piers:baffle piers:Head on: Dis- :of outlet:At center: Rt or lt Remarks basin: in basin :on 2:1 apron:culvert:charge: channel: of :of center

design :Row :*x (ft): (ft) : (ft) :(cfs) : (ft) : ~hannel :of channel: 5 : G : 30.0 : 3 : 15.4 :11250: 332.7 : : 9.7 :Basin baffle piers slightly increased 5 : H : 10.0 : 3 : 15.8 :11250: 332.7 : 9.2 : : the headwater elevation and depth 5 : F : 10.0 : 3 : 15.2 :11250: 332.7 : 9.3 : : of scour 5 : F : 10.0 : 3 : 15.5 :1,250: 332.7 : 9.5

: I : 20.0 : : s : : : .: 5 : I : 7.0 : 3 : 15.7 :1,250 : 332.7 : 9 • .3

6 6

6

b b

7 7 7

7

E : l.4.0 : F : 21.0 F : 18.0 E : 7.0 F : 16.0 F : 6~0 I : 14.5 E : 20.0 r : 11.0 E : 7.0 F : 16.0

:None: :None: : I : 6.0 :. F : 1~.o : D : .o

:

. .

.7

3 15.2 :1,250 3.32.7

.l : ~ :l~0 m.:1 2-2

.3 15.0 :1,250: .327 .3 . :

1 : 15..0 :1,250: 330.9 h2 1 : 15..0 :l~0 327.3 3 15.a :1,250 : 327.3

:.. .. . .o

7.9

1.2 9.3

h2 s.J

. 9.1

:Headwater too low :Good flow distribution

:Good flow distribution

:Headwater too low :Outlet channel lowered

:Outlet channel raised :Outlet channel lowered :Satisfactory flow distribution

8 :None: . . • • < • -:::r:·- ·-,-,- • <-• ·< • . e-7 --- :Good flow distribution and nominal - J 8 : J . 5.8 . . . scour

8 ·:None: 9 :None: :Headwater too low

I-' 00

Using Different Model arrangement

Height of:

basin:_ in basin

Table !!--Continued

SUMMARY OF TESTS

. - -- - ,--, . :of

desiJ.m :Row :*x (ft): (ft) : (ft) :(cfs) : (ft) : channel :of channel:

Remarks

10 : None: : : : 600 : : Good flow distribution and nominal 10 :None: : 3 : 15.3 :11 250 : : scour 10 : None: - ' - - · - · -10_ :None: 10 :None: 10 :None: 11 :None:

. .. . •. :Good flow distribution and nominal scour

*x is the distance from the downstream end of the culvert to the baffle piers, Figure 21.

A

For embankment not shown and emergency uverflow dike see Dwg. 50-0-2664 -iN s-

Slope ~<!,!_rected I ,,24" Minimum layer of riprop over

-<JN

\ ,i-..

f-1 c1. ~ .., i;;

' '

..,, ____ .;,'-----El. J53.0------6-r

: poyline for excavation . : I

h Y Iv ,

! I; 8 0 I ~ J:i ~8 I

I I.

Ci

~ I · ~~ ! / ,::: i : / -- ------Cl I Cl ~ I: II : ! ,.' ; ... ,.--- .... , .. .. I ' q,,-C: Ii u I / I ,. ..... , ..

"' I "'6 ..., -.e ~ i(/)

~ : §~ If i I .. ',,\ \ c::

t I " " f _1 i C,, ·-e I : ~~ ~ ! ~ ~ ~ Q.: :Q.:o -;- c::~.,,_a a: I ,-Outlet Channel

' Sta. t+34 o \~o '---<';' • [B Ji1,,; ..._ -. "'l5 -• _, 'fl (..) CID ~ c:: -~ -

I -- ~---_.._ __ +--'-.--fl---":-1'---m- ....._ -t- a_.._ Q. __ .,

l ,-"I, 8 '.'!!'. I ..,. (B .l!! o ., :;:: "'- · ,_, , ~ 1 · \ @, ...... a .. CJ t ()

\ I I I ;:)._ ..: 0 CJ'-'

~ : : i .. 9 (J) 't t ~f

Warp to J:t as directed)

I , ..., ., --1-+---,1+1-- -1.-~------l Q::, a Cb ~ : ..... ~ \ I ,._ ,/ 9 ~fb

: &~ \ ~ • .. _J_ ___ ..... , / ~~

I ... - . ... ' ,,- , .., : o....._ I ~ • ' \. .,.. / ~ ...._ I

wit 1 _\ _____ , __ \_ r----~-~::::~·: __ _ -:~:~ ____ j.z_-~-----I I : I \ I 1 I / I

: I I ,

' <;>

I' : Ii ,_'

: I Ii_ ___ " I

:Pr>-1 i I~

I .,,.t ':!"

_,::wastebonk as directed------.v-'T'

::;~<.,._ ,..t_. u SL>-_./ PLAN I .·

:-c---24'-of-...;.,. .. ,aco!-~12!.Q½<-f2'-0~-----J7°7J:-----~ ' '6''''- ' ' ' ' : El.353.00--9t·v:-- : : ~ :

h ~- l . _,-+Et. 345.oo :

·• l - ' ,/'f p341io- ~+--LN.G.S.

,, • -=~-.' -m '

'--El. 334.00_/

SECTION

10 0 102030 40 50

SCALE OF FEET

d·r--- ... i:s .,':" ~?

~ uo .... "' ~t <5~ ..... ~v,

(_-.LI

-I

,,· Symm. about { ·:' except as shown

'.--- - - --- - 10'-o'!. --------T----.J4!..o'!---->:

ELEVATION B-B

1:1-

-E/.353.0

'i'-J~,2· ---Compacted backfill

SECTION D-D

,-El.353.0

-fl!.~'1}. eTN.G.s.

SECTION

~ c:

,-Ef.345.0

Backfill-:;' ~~ c:, _(

y

->i~-,2·

IO

SECTION F-F

0 10

SCALE OF FEET

,,,-El.353.0

_,--Backfill-__ _

-~~12"

SECTION G-G

,-N.G.S.

-----------------

SECTION H-H

20

SECTION

SECTION

SECTION

El. 345.0-.

-<..5.~-.EJockfill ,~ -~:..C:..12"

,N.G.S.

N.G.S.-,

J-J

K-K

-Backfill

L-L

Wostebonk OS ~irectedft\OalW,il,t I

11:t-

SECTION M-M

SECTION N-N

,-fl. 353.0

FIGURE 14 REPORT HYO~ 359

h~'-'1 ,.- -~ '

N.G.S.-

Compacted ,/ e_mbonkment--'

s

"' ·o:., .. '9 ti~ .....

10

SECTION C-C

SECTION P-P

0 10 20 30 40 150

SCALE OF FEET

Bockfill----u' ~ wwwl

,-----, 1:1-'

tcampocted embankment where foundation is above excavation line or noturo I ground surface.

SECTION Q-Q

ESTIMATED QUANTITIES Concrete in structures _________________________ 265 Cu. Yds.

Concrete in floor slob, paving, and baffles __ .. __ 62 5 Cu. Yds. Reinforcement steel. ___________ . __ . _______ 135,000 Lbs.

REFERENCE DRAWINGS INLET TRANSi TION. _ .. ___ . ___________________ .50-0-2666

CHUTE ANO POOL -- _______ . -- - --- _ --·. _ -- _ -- _ .so-D-2667 OUTLET-WALLS-PAVING-BAFFLES. ______________ . 50-D-2668

MOHAWK PROTECTIVE DIKE No. I - STA. 0+00 TO 33+24.71 AND OUTLET CHANNEL-------SO-D-2664

UNITED STATES DEPARTMENT OF THE INTERIOR

BUREAU OF RECLAMATION

GIL A PROJECT - A Rt ZONA WELLTON-MOHAWK DIVISION

MOHAWK PROTECTIVE DIKE No. I STA.O-,.00

OUTLET CONTROL STRUCTURE GENERAL PLAN AND SECTIONS

~ DRAWN .. _____ flllo!'_._'4, ..... SUBMITTED .. !.~Jiif!f!O_~--- __ _ ~ TRACED. ____ _ B_.f:.,_~:. ____ RECOMMENDED _ _(!.__~--'!~~-- _______________ _

: CHECKED_1f:~.2.:~~APPROVED.-~-E:f-1:.~r:::-€,.-aiN€«·111--------

~ DENVER, COLORADO - DEC. S,"49 50-0-2665

~ ·;;; "' ~ .. .... :,: - )le--.; .!!ct~ ~-c.\l .._._I 0 "'"" ~· .!! ::,C) ·- C.:,W) ~ . ~~r ._ oc::,

~

FLOW

c, or>- Ej

Sr>-I I I

'

Ff>-

T -f -

., -"" fl@12·--

~ ~

OJ ~ =··l1 ~ -~ AL

_, ...

... • ~Structure s:t_mmetricol '"' ', about I

, Y 1r=-i.-=--t -=--------.--777 l ,-------------- -

.., _, !!!

. "' ,;:; __ .., _, ... @,

7

sL: I I I I I

~ "' I I I

:

C~ ,oL

...... ~

.,, :'l

~ .... I

£~~ - rn OJ ~ ~ I I

_t _ _}__

PLAN

r----,--Reinforcement OS shown - - - - -- - -- - - -- --- - -- - - - - - - - -ioo,_',:/;~forcemenf OS - shown in -- - --,Re_inforce,r,ent OS S1-n ---- ---~

• : : in Section C-C. : Section D-D : ,n Section E-E. :G Ir i •• ,_ '•" ., t ·~ ) I J"...., ---- ------------18-0---------,-----"10,.._---------22 -6 --•---------------------,-- .- ----50-lv-----'.------ ,

, : ' «-----6 •4 ----~ --Reint neor foce. Lalll}if rein/.

-.;, _, "'r _L_

_JA

\Sta. 3t-26.II

I

--- t

~~--r-: .. 5' ...

- Culvert Section Type o--/ • : orra11911ment bath focas. . ~ IJ' rr,o· I = .-j #@ 12 ' ' ' j t ! ,, t

I I 1

) I ... - ",' : 11::±.;f=it~L : • ,..__ .......... '"""_ .... ____ }_

• ,---@)/2-•" ,- ' I L-------------------- >-0

~ : ,-/' I I

I

_} ___ ~ .... .. '.' ... 6~-~~·11_e~--- -12• I l------: : - -- -·-----· :::~-~~:-~~-.... ' • .,t) : l

~ 1 ./ ,' _ f O @12 •. __ ~ {!, ;Reinforcement as shown ,

•' I @l2- , For face re1nf.-- 11@12"--. I , in Section F-F.- '

_'? / J r,- 'd!J=:1:±±.J;Ui .. J I • \ :

~ J"Fillets:, 'r' ' _ _, Y :..0-------9~,r--'L--->-<

\ .L#@12~J---- /I • , 1

£1_ 334.oo--···, '- · • -------- @ 12--, ,

_t.l'__ . . .. . . . . . . . ... . ~=~~~b±;;~€~,~~~~~ft ' --:r-· . ..,

0

SECTION J-J

~-'~-~ I ~-~ .. ~~-~--~-;: I ·.·.~: !

..... J.1 @12·---' "' -..1. ~ @12" :

t\l • - 2

I

SECTION A-A 0 10

SCALE OF FEET

SECTION H-H

{[f~r] 11@12·--f- - .;: j

J u1t--t -J\_ @i2·

DE TAIL A

I I

I -----i--

'"-1. "' ~

'-,,;; /I ..

, I 0 / I \,Q

, '0 , .., , '

l -~: r -fL.l'. ---, '6"~ • - -

• Yo· e -- ..,. ----,. '8!.. .... ~, ...._

-lo,/ ~

4"- --{-- - -- -s·-,01·- ---­·-+£ 6 • Rubber

f waters/op

. ...

•' ...

¾ '@ 12:,.

' f '@/2"·/.

-.l--...

FIGURE 18 REPORT HYO. 359

i,.--Symmetricol f<- --3~0"-- ->-1 I obaut l I o

: }<-24•-~ O O I

' ' '

·i(t21· '{; 3"Fille;i _ ' __ :~f1@12'

I . I • I •• -8

-~!12• :· , 1", ... : t \

0

I 7~~~

• I

' ·' .., _, ...

I I I

~

ELEVATION B-B _i I 4.-~- :_,r.:rt:1:-.- 'iii-.:~;-_.-~·-:£,.:__.

~- -3'-s~---~

,.,:;:·.·.,.

I Lc--24~-,.j 'i_..(.l. #@/2'

"'·:.D,.:~-

':"T

0 _, ..,

-~Jf)-~

d-'@12·

1:,.

-----1 #,::, 12· -----,_- lW '•,

:1-- f 1@12· '\ 0 \ -, \

_7_ - - 41-6"- - -->-4 \

I I

f#@/2"---.

', 'I

:_3'-6" --->i : } ,;2 : :~:~~<.-:4i. _._ J r J

_J~+. I

f '@12!l-';;~ - -- - --1'-o"-- - - - - - ->i '-i.,

"" i-s,,lic~ at (

r' ' 10·-,./, -1t t

It--¾#

I# ~. J -- .. -r.

');•·

,H • -:, • @12,--- _--, .

·~~f- ~ : .. .

:~,_f #@12·

' ' : f:t ~ [-1/

S.£C TION D- D

£

<5 0 E E

"' ' -- - - - - --5'-6'- - - ->l ~ ~ : I I

'

~

_L~~@;2. i · 2 f Norma/---'

'·-Splice at (.

SECTION E-E

f ,-----H- j ~ 1 1' • 1- ,2 ·--. _ :

\ ~

0 ~

~ IH@12·--,,_ (\& • l'

' -,

1-~~-1lll_ \.jf@12· I , ...

' . ,, "' _, "' I "&: 0

----4'-6"---->1 ~ ,--t 1 @12· I~

,.-1, cl'@12· i 7ri 1@12" I 'I' I

b~

~------4'-o"----~----- ----7'-o"-------J-, ' 2-f-Normti~:

SECT/ON F-F

~

"o 11:, IOO tt':-,_ .. ~ ;: .,

"' .., "'

~- -~!.o!--~ ,

_.., S?

SECTION TYPED

c-c

,-Ex tend tap bor olong edge

\ , .-1- # @> '°· End olternate ..,_~ '. bors 4~0 • from bock

~-.J \~ace of wall.

· ~\ :f # From cut-..._., , off waU. ...... ....,,

,

<-11,m· SECTION G-G

0

SCALE OF FEET

NOTES __ For General Pion and Sections. s~ Dwg. so-o-2677. Chomfer oll exposed corners I un ss otherwise shown.

Install copper noils in concrete last loced. All reinforcement sho// be placed so tho/ the centers of bors

in the outer layer will be 2 • from face of concrete

unless otherwise shown. Lop all bars 34 diameters at splices, unless otherwise

shown. concrete design based an a compressive strength of

3000 lbs. per sq. In.

UNITED STATCS DEPt4RTMENT OF THE INTERIOR

BUREAU OF RECLAMATION

GILA PROJECT-ARIZONA

WELLTON-MOHAWK DIVISION

MOHAWK PROTECTIVE DIKE No. I -STA.12 +:,o CULVERT UNDER DtKE

OUTLET STRUCTURE

oRAWN ___ B.E.s. _____ sus1t11rrcD_ F. E. RiPJJon ___________ _

TRACEO ____ 'i,~!/.,. __ ___ RECOMMENOED __ °.:_L._ R_j~e ___________ _

CHECKED--~·~'!· _H;_G;S.:__ APPROVED_ !f._ ~ !'E.!!_~,';;rr,,,r,N"J:0- - --=_=

Of!NVl!R,COLORADO OEC.23,1949 •so-0-2679

~------i -- 110-.9------------~ : I

··r"f o<p I : !

E--------1--------.a---j'. I I

--T ~IIN

9 _, T

I I I I I I ,. I I I I I ,,

0 I

Q

'----+---+-+----->--L-k I I I I I I I I I I ~:w

a, _, :

I I I I I I I I I I

-f-A : f I

: =~

-~ I I I I :

1----------!-:--I--J,'-----------J.--f ~c ~ i U I o I r i __ J

0 -Q I I

l I I I I I I I

=(D :

--A I :I I <D \

_I I ,__ ________________________ J __ l I I

k. --------------- .. o ,01·-·-------------------J

349

---.,, .......... V'

,,,,,'JS ..

>) I I ,, "' ,., "' :

.::-.L-----·-j r··--,8-,Z- 0 -·->J

-.,, ·" c.o it'-.--@, / , .......... ~ I I 9 r ,l ,/ c::t ',i, 9

' I <:;, I I r::t/

/ I ~ '/ / c::/.,

.J, I r::f'?; '"- c:r· /'1, "';a. ,, I • -~~.z

I I

-;0-,Z---

h,64:';SI I I

-~ I -~ \.._ ___ __

11 11

.. £...: t,---,6-,1--1 I I 1 I 1 I 1 1, I I

--r·1 ' I '.J, I

_, I T --l

=-JN -r

_ _i

..... .. 1e

I I I I I I I I I I I I I I I I I I I

I I ----l i..---- -;;O-;t,------ ->I

Fl.GUR~ 19 REPORT HYO. 359

z ILi 0 :ii::: (I)

0 > _, C a: "' ILi 0 lll:: 0 31: 0 :E

.<( z "' ::c ::::, _, 0 <C :I: " I I- ., z a: ~ 0 ILi I- > ..J ..J ..J LI.I ::::, 31:

0

FIGURE 20 REPORT HYD. 359,

-r - ,·End of

_ J _ --:,-, _c_u_l v_er_t_,, __ . I I

I I

k--10¼>·---~ I I

DESIGN I (Preliminary)

-i--j __ f-+-, ---1 i-----. ............

I k-----30'-o" -_______ J I • I

ru1 ii• a:1

[]1 Ill]

---,;: !

·' -.. I

N

'

- ii,-- · -'Ehd of _.}__ ~ culvert

T-, ., ..

·,!,,

I I

l----,s'-o"-----~ I I -~:

"' a:,

T, Symmetrical obout 'l-··, _·L-~-- _.,__ _ _.__,__,_ m -m~---

D£ s I GN s 2 AND 3

~~~--.L.[]u...,_ __ .L.rn~ ___ _,__i_ Symmetrical oboul £.,·,

DESIGN 4

-.J,-- ,,E~ilv~~t

_}_i-t-, ---------­' ' ~-------22'-6"- ------~ I I

Symmetrical about l----,

-.~- ,End of

_!_·I-1-·-'_c_ul_ve_rt ____ ~""""""

-f­·1 -~ : Symmetrical

ITT D,ESIGN 6

, oboutl---, 1--·f-',---- L---.L..- -~--~~-

DESIGNS 8 AND 9

349

ITT Symmetrical

about t-·

"' '

DESIGN 5

[]

DESIGN 7

-4--."t--H------~-='<,-!

Design 10-With filial upstream from step Des'ign 11-Withou.t fillet upstream from step

--r i : ~ ·.h

T

T­: .,

-+, :

__ j_ Symmetrical

_L_,...._obo_ut_l_-_-_-·,---~--~~~~-

WELLTON -MOHAWK DIVISION

CULVERT UNDER DIKE

VARIOUS STILLING BASIN DESIGN'S I: 12 SCALE MODEL

DESIGNS 10 AND 11

[]

---i-: . .,

·,!,, T I ___ L

•••

,,-End of culvert ' (Reference point)

-----------_x -----------,--Row of baffle pie1'11

,- shown below

REFERENCE POINT FOR LOCATING POSITION OF BASIN BAFFLE PIERS SHOWN IN TABLE II

ROW A

ROW B

ROW C

ROW 0

ROW E

ROW F

ROW G

ROW H

ROW I

ROW ·J

.. 2'-9~--4'-6'-..i..--3~-~ l<---4"-6"--..1.----3'--.!..-- 4"-6'--.l.-2•-9•-, ~~i, I f------1 I I ~~\•

I

!------------------------ anls~, -----------------------~ I • ! I I I

•---- 6'-3~--+--41-&!...:-3 IG-- 2!...,,j,c--41-6'!.-12·-+--.:. 41-6'!..-+-- 61-3·----.a

I

2'-5" I '-4~'-3~2'-4" 2'- " 2'-4~2"- "' 2'-4 2'-3~'-5"

~---------~ ------- --------------30"-25'------------------------.~

1·-11----4"-6'---of<---4'-6"---<>l<---4'-6'!.-...j..--4'-6"---+---4'-6'!.--¥

11-1.-r,.r-3 11·-1.;i--2'-3~1·-rf~-2•-3•..J1·-1.~•-3·~·-1.t1,t2•-3~1·-1.1·~·-3"~1·-1. I I I I l I I I

I

~----- .--------------------25' -----------------------~ ' '

I I I I I ~ I I I 1 I 1 I' l,-2"-3,W 2'--2-fl--2"-3">: 2'--2-ft-2'-3' 2"-2ft"f"-3"i 2"2-tl4-2"-3\j 2'-2-fj.2'-W, I' I I I I I I I I

~------------ ---------------26"-6" ------ - --· - - ---- --------;

WELLTON -MOHAWK DIVISION

CULVERT UNDER DIKE BAFFLE PIERS TESTED IN STILLING BASIN

I: 12 SCALE MOOEL

...I~· ------r 'I' ___ L

' I !--2"-6"!

-..!~, 1'!--- --,.--

~ --*-

~2'-&!ot --.i~1·1t-----r-.,

l _ _j __

i-2'-6'-! I o

->1~' ~o· ___ r ·' .,,

___ j, __

l-e'-3"i .

I ' r 2·-; D----r ., .. ----*'-

k-2' I ---T D . 'l' ____ L

... ts' :.io· ---r ;;. I. ___ .i__

l-e'-3~ ... ~· '10·---r·

7 ----*--

!-2'-3'1j

FIGURE 21 RE

A. Culvert transition flowing partly full.

FIGURE 22 Report Hyq-359

B. Flow over baffled apron. C. Resulting scour pattern.

WELTON-MOHAWK DIVISION CULVERT UNDER DIKE

Operation of Design 1 (Preliminary) with outlet channel at Elevation 334 feet.

Discharge = 1250 second-feet at head of 17. 5 feet 1:12 Scale Model

A. Baffle piers, 3-feet high, on apron.

B. Baffle piers, 5-feet high, on apron.

WELLTON-MOHAWK DIVISION CULVERT UNDER DIKE

Discharge of 1250 cfs and resulting scour for Design lA with 3 - and 5 -,-foot piers on apron.

Outlet channel elevation = 334 ft. 1: 12 Scale Model

FIGURE 23 Report Hyd-359

A. Baffle piers. 3-feet high on apron.

B. Apron baffle piers removed.

WELLTON-MOHAWK DIVISION CULVERT UNDER DIKE

Discharge of 1250 cfs and resulting scour for Design 2A with and without piers on apron. Outlet channel elevation = 334 ft.

1:12 Scale Model

FIGURE 24 Report Hyd-359

A. Design 4A. Outlet channel elevation = 334 feet.

B. Design 8. Outlet channel elevation = 327.3.

WELLTON-MOHAWK DIVISION CULVERT UNDER DIKE

Discharge of 1250 cfs and resulting scour for Designs 4A and 8.

1:12 Scale Model

FIGURE 25 Report Hyd-359

FIGURE 26 Report Hyd-359

A. The model prior to scour tests.

B. Scour pattern after discharge of 1250 cfs.

C. Discharge of 1250 cfs and resulting scour pattern.

WELLTON-MOHAWK DIVISION CULVERT UNDER DIKE

Operation of the recommended design. Outlet channel elevation = 320. 3 feet.

1:12 Scale Model

A. Discharge of 1250 cfs and resulting scour with out­let channel at elevation of 328 feet.

FIGURE 27 Report Hyd-359

B. After discharge of 600 cfs. C. After discharge of 1250 cfs.

Scour patterns with outkt channel at Elevation 333. 5 feet.

WELLTON-MOHAWK DIVISION CULVERT UNDER DIKE

Operation of the recommended design 1: 12 Scale Model

"' .. '°

346

342

338

I-

: 334

IL

z - 330 z 0

1- 326 ct > Ill ..J 322 11.J

318

314

-- ' "

' Flowl i>-

I ,,,. ,,,,

,..-Top of1traini1ng wa I - E1~344.o'o

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

~ "-.. i-----1--,, ..... -- ---- ---- ---- ......... \ .,

>,-End of culvert tran~ition ~~ \ I .,- El. 334.00 l~r; ~--

.. ' ' ., ' ' \~

~ ~ '~

--- Discharge of 1250 cfs. ----- Discharge of 600 cfs.

I'--........ ...............

............... ---- I'\.., ...,_

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

I,. ~ :---_

Nl --,...,

~ ~ ~

''"

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

"-......... , .. ~ ............... ,....,_~-~~

....

~~

.... -.........

' _.. 1- .r:.-.: ~: ~ 0..:..3 ----·

~ ,

Channel elevation at beginning of test.

0 4 8 12 16 20 24 28 32 36 40 44 48 52 56 60 64 68

DISTANCE FROM CULVERT IN FEET

WELLTON - MOHAWK DIVISION

CULVERT UNDER DIKE WATER SURFACE PROFILES

I: 12 SCALE MODEL

21

"' , ... o-21 G) .... c :E :a -< Ill .. ;,.N .... '°

... ... ...

r--, I I

=b _, N ;-

' I I

_L_

,J:i~tr~11 :; 1.p I 11

l

#2 it-~!-~---4#6 #3 -lt----x- =11'4 =11'5

'

r ---------------- 'r4-~·-~~·--- 21'-o'~------~J

' ~ I - 2·-' I , I

#74-----#8

=11'9

PLAN

I I I ' 6't------~ 1<-------19- ----- •

' : I

#~I : - - I ' I

--, 611 J .., -.:, N I

' I I I I I I I I ____ i

#1,2,3- #4 #5#6 #7 #8 #9 =#10 =#II _...__ _ _.___.....__ ______ ....._ _____ __J.__ _____ __._ ______ .__ _____ __._, __ =l

PIEZOMETER

DESIGN 2 1250 cfs.

DESIGN 2 1250cfs.

DESIGN 2A 1250 cfs.

DESIGN 2A 1250 cfs.

RECOM- 1250 cfs. MENDED

DESIGN 600 cfs.

ELEVATION

LOCATION OF PIEZOMETERS

PIEZOMETRIC PRESSURE IN FEET OF WATER

I

-0.9

-5.0

-3_5

-4.9

-6.0

+0.1

REMARKS 2 3 4 5 6 7 8 9 10 II

+ 1.8 0.0 +10.7 -0.8 -0.6 -0.4 0.0 -1.0 -t- 1.2 -t-0.2 H = 17.5' Transition party full.

-1.2 +0.9 +2.0 -8.6 -4.6 -4.8 -4.5 - 1.5 -1. 7 - 1.9 H= 12.5' Transition flowing·full.

+ 1.8 +2.0 +2.3 -a.I -4.6 -3.0 -2.6 -I.I -2.4 -2.4 H= 15.o' Vortex in headwater

-0.1 + 1.6 -3.5 -9.5 -4.4 -4.0 -3.9 - I.I -2.8 -2.9 H= 14.5' Vortex removed.

-8.6 -4.0 -2.5 -2.0 -3.0 -3.6 -4.1 -4.2 +0.6 +2.6 H= 15.3'

+4.0 - +0.1 +0.9 +0.6 +0.9 +0.7 +0.5 + I. 7 + 1.5

WELLTON - MOHAWK DIVISION

CULVERT UNDER DIKE

PIEZOMETRIC PRESSURES IN CULVERT

I: 12 SCALE MODEL

-ID

i ---r

., "' ....... 0-:110 ""'C :c :a -c Ill CJ ;._N .... "'

0 PIEZOMETRIC z PRESSURE IN

N FEET OF WATER

IIJ PIER PIER PIER PIER ii: A B C D

I -t-8.3 +8.1 +0.7 +5.8

2 +7.9 +4.3 +1.6 +4.6

3 +5.9 +6.0 +1.5 +7.8

4 +3.0 +3.7 +1.4 +5.6

5 -0.2 0.0 0.0 0.0

6 -0.2 -0.3 0.0 0.0

TABLE OF PRESSURES FOR Q = 12 50 c.f.s.

,¥ u 0 :0 It­o

c,,i I" --+2-- _l,'.'..>1

4 I

,.-Upstream end of apron

A

D D

D D POSITIONS OF TEST BLOCK

ON APRON

------------'---,;--r------+, --+- ;· _! : I -r<'I

---J--+.-- :~ i I I I'll• I

I I !-----------~--'{_ __ 'f._......_ ___ _. i . I 11 :

j< ---------4 2 ------- >t

349

UPSTREAM FACE

LOCATION OF PIEZOMETERS ON TEST PIERS

WELLTON -MOHAWK DIVISION

CULVERT UNDER DI.KE

PRESSURES ON BAFFLE PIERS

I: 12 SCALE MODEL

FIGURE 30 REPORT HYD. 359.

A. Piezometers at entrance to culvert.

B. -::>iezometers in roof of culvert.

WELLTON-MOHAWK DIVISION CULVERT UNDER DIKE

Location of Culvert Fiezometers 1:12 Scale Model

FIGURE 31 Report Hyd-359

PART III--WASH OVERCHUTE AT STATION 938+00

Introduction

The wash overchute at Station 938+00 is one of four over­chutes on the Wellton-Mohawk Canal. The other three overchutes which are similar in design except for width of structure are located at Stations 234+60, 563+50, and 660+00, Figure 32. Although model studies were conducted only on the wash overchute at Station 938+00, the results and recommendations evolved from the ~tudy may be applied to the other three structures.

The wash over.chute at Station 938+00 is located 1/2 mile north of Wellton-Mohawk Pumping Plant No. 3, Figure 32 and is designed to carry the discharge from the culvert under dike over the Wellton-Mohawk Canal into a natural channel which enters the Gila River approximately 1 mile downstream from the overchute.

, The overchute, Figure 6, consists essentially of a concrete slab with training· walls bridging the canal; a vertical curve which results in a 3-foot drop in grade after crossing the canal; a horizon­tal section, 22 feet 8 inches in length, referred to as a stilling basin in this report; and a baffled apron on a 2: 1 slope at the downstream end of the structure. Like the culvert under dike, the overchute is designed for a maximum discharge of 1, 250 second feet.

The model studies were used primarily to observe the acceleration of flow resulting from the 3-foot drop and the effec­tiveness of the baffled apron.

The 1: 12 Scale Model

The hydraulic studies of the wash overchute were conducted on a model built to a geometrical scale of 1 :12, Figures 33 and 36A. The model consisted of a head box 7 feet long and 10 feet wide con­taining the topography upstream from and the entrance to the over..; chute, and a tail box 11 feet long and 7 feet 6 inches wide containing the stilling basin and baffled apron. A flume which connected the two boxes represented the concrete slab over the Wellton-Mohawk Canal. The head box, tail box, and flume were constructed of wood and ~ned with galvanized sheet metal. The topography in the head box, the bottom of the flume, the vertical curve and the stilling basin were made· to grade by forming concrete to metal templates. The 2: 1 sloping apron and training walls were constructed of 3 / 4-inch plywood while the baffle piers were made of redwood.

19

Water was supplied to the model by a vertical turbine pump and metered through a combination venturi and orifice meter. No tail-water data on the channel downstream from the overchute were available. Therefore, flashboards were placed at the downstream end of the tail box to act as a control and to hold the sand in .the tail box.

The Investigation

General

Six different baffle-pier arrangements, which varied in size, shape., and spacing of the piers on the 2:1 sloping apron, were tested in the investigation. These arrangements are designated as Designs 1 through 6 in Figure 34. In addition, tests were made with different baffle-pier arrangements on the floor of the stilling basin (the hori­zontal section immediately upstream from the'baffled apron). The baffle-pier arrangements in the stilling basin are shown as Designs A through G in Figure 35. In the following discussion, the various baffle-pier arrangements are referred to as Designs 1, lA, lB, etc. The numeral and letter, respectively, designate the baffle-pier arrangements on the sloping apron and on the stilling basin floor, Figures 34 and 35.

The effectiveness of the various baffle-pier arrangements was determined by erosion tests and visual observations of the flow throughout the structure. The erosion tests were made with sand molded in the tail box before each test to conform to the channel down­stream from the structure. Most of the tests were run· with the' sand at elevations 275 and 264. 5 feet for 30 minutes which is equivalent to approximately 1-3/4 hours in the prototype.

Design 1 (Preliminary)

The model, Figure 36A, was initially constructed according to the preliminary design shown in Figures 6 and 34A~ and operated at discharges of 600, 1,250 (design discharge), and 1, 875 second feet, Figure 37. Although the structure was designed for a maximum discharge of 1, 250 second feet, it was later determined that the over­chute might carry flows greater than anticipated, and the model was operated at 50 percent above the design discharge.

For discharges above approximately 1, 000 second feet, the baffled apron failed to retard the flow before it entered the downstream channel, Figure 37B. At these discharges, the flow swept through the stilling basin, struck the upstream row of baffle .piers on the 2:1 sloping apron, and was deflected above and over several of the lower rows of baffle piers, Figures 37B and C. Thus, the effectiveness of the lower rows of baffle piers was considerably diminished. With a

20

discharge of 600 second feet, the baffle piers appeared very effec­tive, Figure 37A. The scour pattern for the preliminary design after the maximum discharge of 1,250 second feet had passed through the overchute for 1-3/4 hours (prototype) is shown in Figure 36C. The deepest scour was 12 feet below the original channel bottom (elevation 275. 0 feet) and occurred near the center of the channel immediately downstream from the baffled apron.

Design lA

. Since the flow swept through the stilliiig basin _at all dis".' charges, it appeared that if a hydraulic jump were made to form upstream from the sloping apron, the velocity of water would. be decreased and the baffled apron made more effective. For Design lA a row of baffle piers, similar to those on the baffled apron, was placed at the downstream end of the stilling basin, Figure 35A.

Figure 38 shows the model discharging 600, 1,250, and 1, 875 second feet. At all flows the hydraulic jump remained in the stilling basin and the baffle piers on the sloping apron appeared to be effective. Results of a scour test with this pier arrangement showed the greatest depth of scour to be 7 feet which is 5 feet less than that obtained with Design 1.

Design lB

To determj.ne the best lQcation for the row of baffle piers on the stilling basiJ;i..floor, the piers were moved 6 feet from the downstream end: of the stilling basin in Design lB, Figure 35B. From tests on this design, it appeared that the water accelerated between the baffle piers in the stilling basin and the baffled apron. Thus, to keep this acceleration at a minimuni, the best location for the stilling basin baffle piers is at the downstream end of the stilling basin. The greatest-depth of scour for Design 1B was 9 feet, Figure 39A.

Design lD

A row of nine piers, 2 feet square in plan and 3 feet high, was placed at the downstream end of the stilling basin, Figure 35D. This pier arrangement gave results similar to those obtained with Design lA. Figure 39B shows the model operating at a discharge of l; 250 second feet, while Figure 39C shows the scour pattern after the model had operated for a time period equivalent to 1-3 / 4 hours prototype. The greatest depth of scour was 7 feet--the same as that observed with Design lA.

Design 2A

· For design 2, the spacing of the original baffle piers on the 2:1 apron was reduced from 6 feet to 4 feet 3 inches, Figure 34B. This· change caused no apparent difference in the operation of the

21

model. The hydraulic jump and the fiow down the 2:1 apron were sim­ilar to that observed in Design lA. The greatest depth of scour for Design 2A was 7 feet, Figure 39D.

Design 3

To determine the feasibility of using narrower but a greater number of piers on the 2:1 apron, baffle piers having a width of 2 feet 3 inches and a cross section the same as Design 1., were used in Design 3, Figure 34C. Figure 40A shows Design 3 operating at the· maximum discharge of l; 250 second feet and Figure 40B shows the resulting scour. By comparing Figure 40A with' Figure SBA, it appeared that the narrower baffle piers gave a slightly rougher water surface as the water spilled over the 2 :1 apron. The results of the scour test also showed that the narrower.piers gave a scour depth of 8 feet, Figure 40B, or 1 foot deeper than Design lA.

Design 4

In Design 4, stepped baffle piers, 3 feet high and 2 feet 3 inches. wide, were placed on the 2:1 apron., Figure 34D. With the stepped piers installed, the appearance of the fiow was similar to that observed with Design 1. ·However. results of a scour test, · Figure 40C, showed that more of the apron baffle piers were covered with sand, indicating the formation of a ground roller which moved the sand back on the apron.

All scour tests up to this point had been made with the outlet channel at elevation 275 feet. The outlet channel was lowered to elevation 271 feet and another scour test made, Figure 40D. By com­paring Figures 40C and D, it can be seen that the depth of scour was 7 feet in both cases, and very little sand was moved back onto the apron when the outlet channel was lowered. Thus, it appears that the ground roller forms only when the outlet channel is at certain eleva­tions.

Designs 4.A. and 4E

Tests on Designs 4A and 4E were made to determine the effect on the flow over the baffled apron and the depth of scour in the channel when different rows of baffle piers were placed in the stilling basin. Figure 35A and E shows the size of baffle piers tested, and Figure 41A shows the scour pattern using Design 4E. Although the_ extra row of baffle piers caused a hydraulic jump to form in the stilling basin., there was no apparent change in the appearance of the flow over the baffled apron, and the depth of scour was 6. 5 and 7 feet or approximately the same as observed with Design lA.

Design 5

For Design 5, the height of the upper row of stepped blocks in Dseign 4 was reduced from 3 to 2 feet, Figure 34E. It was felt, that

22

by reducing the height of the first row of blocks, the resistance of the baffle piers to the flow over the sloping apron would be more gradual, resulting in a more even flow distribution over the

· apron.

At maximum discharge, the flow over the baffled apron was well distributed, and the resulting scour pattern, which showed a maximum depth of 5. 5 feet, was the best obtained thus far in the study, Table III.

Design 5F

In Design 5F, three rows of baffle piers, 1 and 2 feet high. were spaced along the /stilling basin floor, Figure 35F. The three rows of baffle piers caused a hydraulic jump to form in the stilling basin reducing the velocity of the flow over the baffled apron. A scour test at maximum discharge with these baffle piers showed the maximum depth of scour to be 4. 5 feet or 1 foot lower than Design. 5.

Design 5G

Design 5G differed from Design 5F in that the hei~ht of the center row of basin baffle piers was reduced from 2 to 1-1/2 feet. Figure.35G. This· change made no difference in the operation of the model. The depth of scour was 4. 5 feet, or the same as observed for Design 5F.

In all ~he _previous tests on Designs 5, 5F, and 5G, the downstream channel was at elevation 271 feet and the depth of scour varied from 4. 5 to 5. 5 feet as compared to 7 feet or more with Designs 1 through 4, which were run with the channel at elevation 275 feet. To determine if the elevation of the outlet channel had any effect on the depth of scour, the outlet channel was raised to elevation 275 feet and another scour test made using Design 5G. Results of this test showed the scour depth to be 6. 5 feet, Figure 41B, or about the same as obtained using Designs 1 through 4. Thus, it appears that the elevation at which the outlet channel intercepts the flow down the baffled apron has a marked effect on the depth of scour.

The fact that a greater depth of scour was observed at the higher channel elevation is probably due to the varying flow pattern as the water passes down the sloping apron. At one elevation the flow pattern may be such that the flow is deflected away from the sloping apron, while at another elevation the deflected flow may be striking the apron. If the outlet channel intercepts the flow at these different flow patterns, varied depth of scour will no doubt result.

Design 6

Baffle piers, 2 feet square in cross section and 6 feet high; were placed on the 2:1 apron in Design 6, F_igure 34F. For all flows, the water "piled up" considerably in front of the first

23

row of piers, Figure 41C, indicating the piers were too high and offering too much resistance to the flow. In general, the operation was poor. The scour test showed that the maximum depth of erosion in the channel was 9 feet, Figure 41D.

Design 6C

To prevent the "pile up" of water at the first row of piers, a row of blocks, 2 feet high. were placed in the stilling basin, Figure 35C. The 2-foot blocks caused a jump to form in the stilling basin, but a scour test showed very little improvement in -the scour pattern. The deepest scour measured 8. 5 feet.

The Recommended Design

A summary of the tests using the various arrangements of baffle piers is tabulated in Table III. In general: the appearance of the flow over the baffled apron was improved and the depth of scour was reduced when a hydraulic jump formed in the stilling basin. With­out the formation of a jump, the water swept through the b3:~in and, on ptrik~g the first row of piers on the baffled apron, the flow was deflectedupward and tended to pass over the remaining rows of piers. The te'sts also indicated that a ground roller formed for some baffle­pier arrangements when the outlet channel was at certain elevations. However.· when the channel was lowered or raised to another elevation, the ground roller apparently no longer formed. See Designs 4 and 5G, Table ill.

It is recommended that Design IA. with a longer baffled apron, be used for construction in the field. The model study indicated this

· design gave a satisfactory jump in the stilling basin and an evenly distributed flow over the baffled apron, Figure 38. Results of scour tests using Design IA. with the channel bottom at elevations of 275 and 264. 5 feet. showed a maximum depth of scour of 7 feet in the out­let channel for a discharge of 1,250 second feet. A nominal depth of scour also occurred for discharges of 600 and 1, 875 second feet with the channel bottom at elevation 264. 5 f~wever, the end of the 2: 1 apron is uncovered for all discharges indicating that the apron is . too short. Figure 42. Therefore, assuming the channel will degrade to approximately elevation 265 feet. it is recommended that the length of the 2:1 apron be increased to include a tot_!ll of at least _seven rows of baffle piers.

Although Designs 5F and 5G showed the least depth of scour when the channel was at elevation 271 feet. the maximum depth of scour increased to approximately the same as Design 1A when the channel elevation was raised to 275 feet, Table III. A detailed drawing of the recommended basin is shown in Figure 43.

24

Water-surface Profiles

Figure 44 shows the water-surface profiles for discharges of 600, 1, 250, and 1, 875 second feet for the recommended design. Profiles for each discharge are shown from the upstream end of the chute to the upstream end of the 2:1 apron.

Pressures on Baffle Piers

To aid in the structural design of the baffle piers on the 2:1 apron, piezometric pressures were observed on three test piers placed as shown in Figure 45A. The test piers were constructed from sheet metal and six_ piezometers were located at points along the sur­face of the piers. Figure 45B. Pressures on the three test piers were recorded for Designs 1 and lA, at the design discharge of 1, 250 second feet (see table in Figure 45).

25

Table III

SUMV.A..~Y OF TESTS USING VARIOUS BAFFLE-PIER ARRANGEMENTS Baffle-eier arrangement . :Elevation: Maximum: .

On 2:1 . In stilling :Discharge:of outlet:depth of: . Remarks sloping apron: basin : seeond :channel, : scour:

(Fi~re 34) I (Fi~re 35) : feet . feet . feet . . Design 1 . Nor.c . 1,250 . 275 . 12 · . :No hydraulic j1.:ip~ . Water deflected over lower rows . . . .

of eiers Desitro 1 . Desitro A . 1.220 . 272 . ? :Good jump in basin. Water evenly distributed over . . . . I>esitro 1 . Desifil! A . 1.220 . 26!r,.5 : 7 : baffled apron . . . Desigg 1 . Desig[! A . 600 . 26t±-5 . t±-1 . . . . Design 1 . Desi6n A . 11875 . 264.5 . 11.3 . . . . Design 1 . Design B . 1,250 . 275 . 9 :Good jump. Water accelerated after leaving basin . . . .

I . . . . . eiers . . . . .

Desigg 1 . Desi&Q D . 1.220 . 275 : z : Fair ,jume. Similar oeeration to DesiEfil 1A . . . [ Design 2 . Design A . 1.220 . 275 . 7 :Oeeration similar to Desifil! lA f N

. . . . Desi&! J :See Fi~re ,2!r,C: 1.250 : 272 . 8 :Fair jume. Rougher water surface over baffled &Eron i C') .

Ii' Desi@ !r, . None . 1.220 . 272 . 7 :No ,jumE• Ground roller fonned. Good scour :eattern . . . . j Design t± . None . 1.2~~ . 271 : 7 :No ,jume. Less evidence of ground roller forming . . . , Design !r, . Design A . 1.220 . 2:z2 : 7 :Good jume. Oeeration similar to 1A . . .

Desigg !i, . Desi,g_Q E . 1.220 : 272 . 6.5 : Good jum;e. Flow over baffled a:eron satisfactor;y: . . . Design 2 . None . 1.220 . 271 . 2•2 :No ,jume. Oeeration similar to Design t± . . . . Design 5 . Design F . 1.220 . 271 . !r.• 2 : Good ,jum:e. Flow over baffled a:eron well distributed . . . . Design 2 . Desi&Q G : 1.220 . 271 . 4.5 :SL~ilar to Design 2F . . . Desigg 2 : D3sign G . 1.220 . 272 . 6.2 :Similar to Design 2F . . . Desi&! 6 . None . 1.250 . 275 . 9.0 ~, . Flow deflected u:eward bz first row of :eiers . . . . :i-.,o JumE• Desi@ 6 . Design C . 1.220 . 272 : 8.2 : Fair ,jum:e. A:eron eiers a:eeear to be too·hildl . . .

I I

" " " ,, ... x' /

/ " / .., / / '-l

/ / / /

I /

I /

// I/

/, /1

I). I

"I '" I

I I I

y q,t-

/

,,."-<.· ~t/•" ,,,,,,.,, 0-".,.,/-#-"

1~~~-

/~cf" --~v'f-

/ /

----

/

/ /

/

/

/ /

/

)/ / / '

.,""/, /." ,," /

.,// / /.

/

cf',~~-,,,,//'!>·

~..;/'!'" " ~,.-~ ~ " "/~~ -·i·~

0

/ /

/

,-'-n;:;;itz~~;":~ y -

/ " BRIDGE

!!}.:~. -Su ~~

/ '\/

/ '

" " " "

- - - -- -- ,'l:> /-,- --/ ", -----

/ " " "

~~ /"'"-

" , " / " sc,.,EDllt.E / " Spec,t,co1,ons ., IV~ 2 -- -7- - - '-

,,o ~---------'-

/l,~ / "

/ " / "

/ " " / /

1S/opes nof sleeper than/~:/ \-·Riprap fo fop of dike / nor f'/atfer than z :/·-- ,/.~;~ unless otherwise directed : 'i'<·12•o·Min ., v -~- & " \ ~· . i ' ;,.'?~,:,; "/ '. ' -,~ ~ \. :,,,c-Heiqht as

: directed : ill'Max.

/ ,_, ~y . . ~ .. --21,<· Min.

Omit r,prap and foe / ~-·-c

1~-.,,..f, -~,.~~"

trench where directed·--· ·/:/ TYPICAL DIKE SECTION

" " " / " / " / " / '\/

/

"

" q,

/ " / " /

FIGURE 32 REPORT HYO. 359

I /// /.)_., ,.,,3 o /~ • .r.lf -+0 ,.,,f' "l{rHE

... ~ '"" ,...u; .. .,.... tf>J/o~ ' -" ~ · ·"' •• .";'"t,... "'" "' ,.... .-,'!!/

•"''~' ~9-·/c;,'1,. ,t,c;,"I / ,,( 1/~· ,,z~ ,.. "4• ~,.ts,' ,{~f.," " ~~ 1l~~ .p.,·,~· ~l O} <;,<,~\> ~i;;{ ...

. / '>,if / " ,:i-f-" ~ <P,/',

/ /

9<Jl~ ,,,, 4.'-<', ,.. _.,,. ,. ,/#1/~---· ,,, • .:-•~ ,. ... ,

1/,";,:,~· ~ " / ~"'~""~~ ~~

' J.<f>/,1._t. - -,.,?-~v ~ ,,~t;_i~ 70~

,<)· •• ,.,. ' /--- ,.-?~,ff.I ~~• ,tff ;..' .,o/< / A~ ,•,.f .11~',I-· v'I-~ "•" '-n. ~1/. ~.,·iO .,,... ,,, --- ,v .... • ,,.,

,,~t-;_l• _., ~ ,,_./ . ~..,/:{<> .,.,, /,, ,¥' / '~;• 'l' ~

~~ff- / \ / ·t' (~·t't"" / /-~',l / -.07 " / ' 1/ Jo,

' v;, -,1' " // ~~..y "

/ "- ,,o~~ / . / " \,;,-c-6 /

~

,.~,~ ·, '-+,~

~ >.~_,;,' ',

/ "~"<,/ / ... ,4\ / .,. / ,,. '\

0.,,!~o~ ~/ ,.t.\~ /' / r;,~ij / "-

/ " '!I 0~ / "- !fl.<F,•+o· ~

/ "- eo't'~.,..., '-~ / ) q'>)~·o· , I

/o'I.;;~ '\, 1 I .,_,1.,~t I !tl :

c,'\!;,~~ ~ I ,:,~ cl"- :.:: :t cl

/ ~' ~· ~ ~ .,, qV I ., ._, "1 / +· !I ~;:;'.~I /

/ ,#· ~! ~ ~ "'' / ~ ~ ~ ~

/ ,,,,~ / " I ,---- __ ,- / "

/<----- / " '/ / '

/X.. / / " /

/

,,..z~~ <,}°t,c; <~" '

1000 1000 2000 3000 4000

SCALE OF FEET

/ ' . s--- --- "', : "'i" /

" cificOfiOP - - - - al-- - - -:>k- ~ --.i.:, {\,

/ . these spe __ - - - Y - ~

ded IP -- - --/, ____ ,]PC~~_ - - - ,,,-Riprap to top of' dike "- - , -...

/ " / ,,,,, :,..'l:>

,_.,." / '\,

/ " UNITED STATES

DEPARTMENT OF THE INTERIOR

/- t.- - - ':<'IZ'O"Min:-. / unless otherwise directed ....... __

, ' ' .--Omif riprap and toe :' trench where directed

-._ //,<'Max.-· , . ," \i--=·····zoco"Min.-···<>j ,-N.G.5. ..,a~ • , , ____ TJ________ ~~ /

--,, __,.-- , .. ·-·~·-·-ZL,"Min. 'k-d (Variable) !;J-;1%,,-f- / \ /' '-/:/ I / ,'

\t' \.\.-,Width as directed~/ : / 'Slopes not steeper than lf'z:/ nor f'latter fhan ·2:11--------·-------' "- M TYPICAL DRAINAGE CHANNEL WITH DIKE \'>f

// " " "

BUREAU OF RECLAMATION GILA PROJECT-ARIZONA

WELL TON-MOH A WK OIVISION

WELLTON-MOHAWK CANAL-STA'S. O•OO TO 9 75 +3-f.79 MOHAWK CANAL - STA'S o-,,ooro o-,,98.66

LOCATION MAP STRUCTURES-DRAINAGE CHANNELS-DIKES

ORAWN: ••••• "'·.Ac.".• ....... SVBMITTEO: •••• ;iflf'.'.~~-TAACEO: _ __ !J_·f"~!'_. _______ RECOMME,.,OED : ___ (2_~~ • __________ _

CHECKED:f:.£"lJl_- ~. APPROVEO: ... __ '--('._?'J... .. ...... ~l--4r:.:., ~ CWl~F CNflNEER

I DENVER' COLORADO OE:C. 7, /948 150-0-2395

"' .. .. r-- ~ .----Stop-log slots I ~ ,. ~------------------.ir,--------1 I I I ' : . ,-Strips to hold .-8.83" .-5.38" : i :' sond on chute----- l , 97 ,. ,:, 2, 3 os" I ! / ~\. ~ r--r- . r---=rr--· -. !!.ii ! ! _ --------Rock baffle ' ' ;., w --i.- --T ! I .~· lllmlllm I i I j I I I =' :,I l ·~ ';.J.-----------t---,, --1.\--ll--ll--\l---H--H-H- m I]] mil]~-~~------;----~,!-- A A ---o-~·- wrnwm [ '~: " I I" I T I]] II] : ··t·7Sp.@4!;2-7; i i m I]] m O]_J_ 1 I I 1---_.l,L.Jl_]L_JJ_.JL_lL..J/-+..L---_JLJ]J...::._J.JL--;-rl-- I ' k •,J.,.: I I I 11 1 911 ' 111 ~ 1 I l ---6Sp.@9j½=4'-9;,----a, -<- 4;; : Sand trap-- -----~ , ! I • i ~ y I ' ' I ! I

1 ___ t

I I .>k,. '" : Ill:

Li:"''::_'::::-;:;.:'.".'::: ::_;------- ·~'------ -- t:::::-.:_~c·~::~::;,_ ,;::::::::· ~:::::·:.J

PLAN

0 6" 1' 2' .. 4'

SCALE- I"= 2'

r-, . I False floor---~~ 1 '1 :.it-1, : . - '--,

=i:o \._ 3" Concrete ' 1'

·t =~ =t ~ i "'1 I l I :

~ i : ------------------------------- --- . --~ --- -25 '-3'!.- --------~--- ------- - - - ----- --- - ------------------- -- - -~

,-1 1.-2", 18" Movable toi lgote

SECTION A-A

WELLTON-MOHAWK DIVISION

WASH OVERCHUTE AT STA.938+00 I: 12 SC.ALI! MODEL

" """11 .. _ ~-~ :c ::u

"'"' " "' i::"' ..

FIGURE 34 REPORT HYO. lll59

""

A. DESIGN I (Pretlmtnary)

C. DESIG,N 3

E. DESIGN 5

'' Symmetrical about l----

B. DESIGN 2A

Symmetrical about l----

D. DESIGN 4

-.--lfj-9~;,,,,,,_

-t-- ' _'z_ _.J I .i,1-Yj ~s,--

24 go. sheet metal braces .•••• - - - - •••

·-----1 spaces @ 2'-3"= 1s'-9"

F. DESIGN 6

WELLTON-MOHAWK DIVISION

WASH OVERCHUTE AT STA.938+00 DIFFERENT BAFFLE PIER ARRANGEMENTS ON 2: I SLOPING APRON

t: 12 SCA LE MODEL

'-5ymmetrical about l

'-Symmetrical about Ii.

A. DESIGN_ A 8; DESIGN B

C. DESIGN C ·D. DESIGN D

E. DESIGN E

G. DESIGN G

WELLTON - MOHAWK DIVISION

WASH OVERCHUTE AT STA.938+00 DIFFERENT BAFFLE PIER ARRANGEMENTS IN STILLING BASIN

I: 12 SCALE MODEL

FIGURE35 REPORT HYD. 359

A. The Model.

B. Tail box with outlet, channel at Elev. 275. 0'".

C. Scour pattern after discharge of 1250 cfs. Outlet channel at Elev. 375. 0 1 •

WELLTON-MOHAWK DIVISION WASH-OVERCHUTE at Sta. 938+00

Design 1 (Preliminary) 1: 12 Scale Model

FIGURE 36 Report Hyd-359

A. Discharge = 600 cfs.

B. Discharge = 1250 cfs.

C. Discharge = 1875 cfs.

WELLTON-MOHAWK DIVISION WASH-OVERCHUTE at Sta. 938+00

Operation of Design 1 (Preliminary) 1:12 Scale Model

FIGURE 37 Report Hyd-359

A. Discharge = 1250 cfs.

C. Discharge = 600 cfs.

FIGURE 38 Report Hyd-359

B. Scour pattern after discharge of 1250 cfs. Outlet channel at 275. 0 feet.

D. Discharge = 1875 cfs.

WELLTON-MOHAWK DIVISION WASH-OVERCHUTE at Sta. 938+00

Operation of Design lA. 1: 12 Scale Model

FIGURE 39 Report Hyd-359

A. Scour pattern for Design 1B.

B. Flow in Design lD.

C. Scour pattern for Design lD.

D. Scour pattern for Design 2A.

WELLTON-MOHAWK DIVISION WASH-OVERCHUTE at Sta. 938+00

Operation of Designs 1B, lD and 2A. Discharge = 1250 second-feet with outlet channel

at Elev. 275. 0 feet 1 :12 Scale Model

A. Discharge = 1250 cfs.

C. Outlet channel at Elev. 275. 0'.

FIGURE 40 Report Hyd-359

B. Scour pattern after discharge of 1250 cfs. Outlet channel at Elev. 275. O'

D. Outlet channel at Elev. 271.0' •

DESIGN 4. Scour patterns after discharge of 1250 cfs.

WELLTON-MOHAWK DIVISION WASH-OVERCHUTE at Sta. 938+00

Operation of Designs·3 and 4 1:12 Scale Model

A. Scour pattern for Design 4E.

B. Scour pattern for Design 5G.

FIGURE 41 Report Hyd-359

C. Flow in Design 6. D. Scour pattern for

Design 6.

WE LL TON -MOHAWK DIVISION WASH-OVERCHUTE at Sta. 938+00 Operation of Designs 4E, 5G and 6

Discharge = 1250 second-feet: with outlet channel at Elev. 275. 0 feet

1:12 Scale Model

A. Before scour tests.

C. Scour pattern after discharge of 600 cfs.

FIGURE 42 Report Hyd-359

B. Scour pattern after discharge of 1250 cfs.

D. Scour pattern after discharge of 1875 cfs.

WELLTON-MOHAWK DIVISION · WASH-OVERCHUTE at Sta. 938+00

Operation of Design lA (Recommended) with outlet channel at Elev. 264. 5.

1: 12 Scale Model

~l ~ ... ~ ~

rr-: -! t

rE Welllon-Maha,,k ',,, r,aqal Slq. 938~00

',

~

C: I

-<7H

~~-----------Rein/ as show~fj?t~-~------------~~

- ~ 111 I

1 \ LJ. /Olft~~ : I t--~.,

r--i ---- ·---! , ~-- rrn---ut~1tf ..JH! I \ - i ffil. .. \ 1 1 rn ~ llrn Symtb. about,\ " ':? . I I' ..., •

I : I 11, ___ ,_.._.,........_~ --- ?------=--rt--•' \ I : I I - @-_c;, - '·-€-was~ Structur11 : l t

' I ~ u ' I ~ ~ : I g ':' : I { :

7 l

~i:f •a Uv, .... .. J. : .i A I ci. : oL-, +--'D I -~ :

: I I ~ : j., ..... I I I ,;:, '

, I I : :

_jA

~; ~:§

: I I J I

: I I ~ •"' ' I I -' I I ~--~--~

_l._ J L_ __ _J --- L--- --- ::::::s======:::J ~ t' ~ · ·-For details of Bridge and

Abutments see Owg. 50-0-24 74

JL A

_;JJ

f'

~ I k, __ _ sL

p LA N -------1 .• • ,.,.,_.....,, _, - --- --- ------- ------::: ":~~-.... ~: ;:- : :_ --j ~, ,, ,.,.,._ r _______ ,,,,. ___ --,t;,;;c_:· " ,., ~ · - - \ ----___ .,,~--- -- ----T , , , _,-- ' " ,

_ ···---41~10/-·----,; . --Remf not shown--,_ o -'lt::T'N_ r-~--Remf both oc

1

• ' q• ------ '

' ~ -- - ;- ': --- -- ,,._,f -•-- -----1···'7 I le

rslop---- 12,..., ,,_ ~<'· , , ,. ,...,, :,--F - . . i ! !JO~ ... --=~-p-,-orcurve I

WO E - , 'j' /0-' / -., - / '

E

- • ,,, ' ~- ,, ' . . . .., - ,,,.,. ..., ' "I ,El 2"" ".,,, , ,,,_, ~ r,,_ •, - , ' - • • .L~ \ E/. 276_70---- . ; I I h I : ~ ~ i'@12, ,l

, ,ci,·

,,<:)

I ~ ' : ,: ,, '

'

SECTION A-A

I O & 10

5 CALE OF FEET

}.'@12• ____ / /

• 1.l (_lj)12·----­• 14• Zoned

Loyer cement mortar __ ,-

i

. I -;i,.c,.! I I _, I I

r·-~1 l A I , ,, I : / I V I I ~r-

Y-1--.f----

Js

.. .... , ~ q

' I ...:., ~ -~. 21 .._. I

~- ,'! I

~--; _ _y_ j_

-1 ,o·:-· tr

f '1/6.· End olternole bars j_: .. ,

Q ~ l "'

al half wall height and ·U bind Info footings 18\ f:·

Q ~ ~ ...,

\ .··· \ r· r/ '@6." End alternate bors \ y: ( at hall wall height. \ .. · I I I \ I \ I

\ / :3" Copper nails @12'. ,' countersunk f I

I I

/ --3'-o''--->I ,.J()" Normal

_ ~ . . . ~-: 10·~- ,f -P@6~ End alternate t. ·_:..,~i<-.,.._·;:::p4~ .-:~--r---, /: I bars of half heel length

¾L'· .. ~"'.'<;r:;-~$ ':" ;; : ]:---11· Normal

2{Ntxma1--' , \""'16"~ ·-2f Normol '•-f I ,i12· '-¾ I @6" Spaced 14• Zoned filter-'

fl@12:,, \ \ I

along 2:1 slope.

SECTION C-C

I t"--,c1

~

.' -Extend lopborolong edge. : ,------¾'From cutoff wall

,--For face

---f I (li)6"End alternate bars 5'-0" from bock lace of wall.

--Near face

J#J"--h.il _ i '@6"End alternate . 'ii~- bars at half wall height

SECTION H-H

3• Melo/ stovepipe

' I I I

-----; I

ELEVATION

,4 Copper noi/j Iii 12: counlersunt t,

1 ~.t Elastic t----1 • filler. I ' r---1

J-J

SECTION B-B

form for weep hole on , E of each full baffle-_,

',, /4 • Zoned filler

->id'~- • , !1@12·

J: : :--·19·;(' ...__ I I .

t: i pii;ffe -7 ',I·~~ ·'i'--·' .

,-}L-:. ,,,-s-}l~)l2~i,

S £CT/ON D-D

SECTION G-G

SCALE OF FEET

3• Copper nails @ 12·, countersunk f------, ,-f Chamfer

~r t- -! !)\)' •'+~l}---Reinf not shown

, _d , 7 \!. \ '., -6" Rubber waters/op ,ns, e,oce-"' ... ~ , '•,f £/oslic filler

SECTION E-E

! s .. ,.

flETAIL A

FIGURE 43 REPORT HYO. 359

::~-i' Copper nails f 12: - coun lersunk t

:,• Copper nails ,i 12; countersunk f--, ,f Chamfer

\ I • Re inf. not shown. - , \ / ,f Elastic filler

\ \ ~_L,'

~ .!):i":¥/\f'1' -:::::::. ', , tc) • ~,

Inside foce-1. Chamfer-_: '-(' Rubblr waters/op.

SECTION F-F

NOTES For General Pion and Secllons see Owg. 50-0-2471. Chamfer all exposed corners ¾", unless otherwise shown. /nsto/1 copper nails in concrete lost placed . All reinforcement shall be placed so that the centers of bars in

the outer foyer will be 2"from face of cancrete,unless otherwise shown.

Lop all bars 34 diameters at splices, unless otherwise shown. Concrete design based on a compressive strength of 3000 lbs.

per sq in.

UNITED STATES DEPARTMENT OF TH£ INTERIOR

tJUREAIJ OF ffECLAMATION GILA PROJECT-ARIZONA

WELL TON-MOHAWK DIVISION

WELLTON-MOHAWK CANAL -STA. 9381'00

WASH OVERCHUTE WASH CHANNEL OUTLET-WALLS-PAVING-BAFFLES

:;:;,;.~~~;~;~;:_·-~~~:_-~;;.:::::~;;~~k"_-_ CHECKED:4P/l _____ (ZJ/.2:°A""""1/!D.- ___ _ ';l.,...~-.l'/1~ __

I !"R.colbNADO-NOV.111.l::r r:-,:~-'.IA "7"'1 DENV ......

~ I • ~

NOTE: Drawing distorted-one horizontal equals three vertical

,,··BRIOGE ACROSS ····EL. 287.93 ,c··--·TOP OF TRAINING WALL / OVERCHUTE

288 ---..---...-------....... ---.----.-----,,--------------..-......

~ I •·••r•crs I ~I~ I~ 11 ~ :::0: ~=,:r: :•=,.~ z z 0

282 I I I · 1 I I I I ....., °"'' I / I 7~, 'I I 1- 280 ic;: --· ct ««<«i.i:_, __ l > ««< «««lt UJ 278 «««l<«< 1 -' ' "'" " «lo ,. """"'' I • 278 m «wV. '5' I

I 11'\:I f'

21~0~-,~---;tc--3~--to:----;;---fc1-~;---d~-~~--:-::b----:-L--f~ ro- 20 30 40 50 60 70 80 90 100 110 120

DISTANCE IN FEET FROM UPSTREAM END OF OVERCHUTE

WELLTON-MOHAWK DIVISION

WASH OVERCHUTE AT STA. 938 +oo WATER SURFACE PROFILES

DESIGN I A (RECOMMENDED)

I: 12 SCALE MODEL

~ ::!!

~ ~

FIGURE 45 REPORT HYO. 359-

z (I) C( CD

Al_ (!) z :J .J

FLOW j:: (/)

IL 0

0 z ~ I

,' I

'

,,-El .. 276.701 I

[] TEST

I I .; . a []

PLAN

jA

d!· t__,.ll.. ~

rJ:i UPSTREAM --,r

FACE

B. LOCATION OF PIEZOMETERS

ON EACH TEST PIER

. a: Pl EZOMETRIC PRESSURES II.I I- IN FEET OF WATER II.I :e d DESIGN I DESIGN IA oz N (NO JUMP IN BASIN) (JUMP· IN BASIN) II.I

349

SECTION A-A

A. POSITION .OF TEST PIERS ON 2: I APRON

CL

I

2

3

4

5

6

PIERA

+ 5.8

+5.0

+4.4

+4.0

0

0

PIER B PIERC

+9.0 +2.7

+5.1 +2.9

+6.0 +2.7

+3.8 +2.7

+1.5 +3.6

+1.5 +3.6

WELLTON-MOHAWK DIVISION

PIER A

+4.8

+4.0

+4.6

+4.3

0

0

WASH 0VERCHUTE AT STA. 938+00

PRESSURES ON• BAFFLE PIERS

I: 12 SCALE MODEL

PIER B PIERC

+7.6 + 5.3

+4.5 +4.4

+ 7.6 +4.3

+4.3 +3.9

+1.5 +3.6

+1.5 +3.6