Reservoirs for irrigation, water-power, and domestic water-supply. With an account of various types of dams and the methods and plans of their construction

Front matter

□□□ED3SflEDfl

Fig. 125—Lower Dam, or “ Presa de la Olla,” Guanajuato, Mexico. View taken* during the Feast Day when the

Gates are raised and the Reservoir emptied.

Preface

In 1896 the author was requested to prepare a brief descriptive account of such of the principal dams and reservoirs as had come under his observa¬ tion in the course of his professional practice in the arid region of the United States, for publication among other Water-supply and Irrigation Papers issued by the U. S. Geological Survey for the general information of the public on topics of popular interest.

In compliance with this request a paper was written somewhat hastily in the rare leisure intervals of a busy season, which was printed and cir¬ culated as a portion of the 18 th Annual Beport of the Geological Survey, in a more pretentious form than had been anticipated when the manu¬ script was prepared. The rapidity with which the edition of the paper was exhausted testified to the existence of a widespread interest in the subject of water-storage in the West, and a general demand for the facts regarding the works which have been built and those which are projected. This has encouraged the author to republish the paper in another form, revising and adding to it as the material has become available. The work does not pretend to be an exhaustive treatise on the subject of dam-construction in western America, nor does it assume to cover the field by an account of all the important dams which have been built. It is chiefly a straightfor¬ ward description of those works with which the author has become familiar, either as a consulting engineer, or as designer and constructor, or merely as an interested observer of the development of the ideas of other en¬ gineers. The field is too great to be completely covered by any one work, and new projects are developing with such rapidity as to render the task of enumerating them all quite beyond the power of any one individual.

For what it may be worth in the way of information or suggestion to the fellow members of his profession, or to others interested in the storage of water, the volume is modestly presented, craving indulgence for all errors of omission or commission.

James D. Schuyler.

October, 190C.

Introduction

The development of a water-supply for irrigation in the arid West sooner or later reaches a stage where the construction of storage-reservoirs becomes a necessity. If the stream is one of considerable volume, numer¬ ous irrigation-canals will be constructed from it at all convenient points, and its entire normal flow will be utilized before the impounding of floodvolumes is thought of as a possibility. But with the varying seasons there will occasionally come a year when the best of streams are so shrunken below the normal as to limit sharply the area which can be irrigated from it, and emphasize the regret that some means had not been provided for holding back the wealth of water which at times pours into the sea without benefit to any one, so as to render it available in the drier part of the year. Other streams there are, which drain very large districts and at certain times of the year are formidable and almost impassable rivers, that in the summer and fall are dry for months at a time. If these sources are to be rendered servicable storage-reservoirs must be built as the initial step in irrigation development.

All streams, except they be regulated by nature by means of lakes or subterranean reservoirs, are subject to great fluctuation. It is the function of artificial reservoirs to equalize in a measure these variations in flow, im¬ pounding the floods for use in the season when irrigation is necessary. Were it possible to conceive of a stream flowing throughout the year without change in volume, such a stream would not have its fullest measure of use¬ fulness without storage of the water flowing during the period of the year when irrigation is not needed.

Inasmuch as the total available water-supply of the arid region is vastly short of the quantity needed for irrigating all the land requiring artificial watering, it is evident that, under every condition and with every class of stream, storage-reservoirs are needed to develop the fullest measure of use¬ fulness of the existing supply.

Unfortunately it is beyond the possibility of hope that all the water flowing can be stored or utilized. There is such a wide range in the total run-off of every stream from one season to another that it would rarely be possible to find storage capaicty for the extremes of flow. On large rivers

VI

INTRODUCTION.

the ratio between maximum and minimum years may vary as 12 to 1, while on smaller streams the total flow one year may be one hundred times as much as that of the next year. Hence the reservoirs which might be pro¬ vided to catch all the flow of average years would occasionally be over¬ whelmed by freshets so extraordinary as to fill them several times over. This condition has an important bearing on the design of every reservoir located in the path of floods, first, in emphasizing the necessity for provid¬ ing ample spillway capacity, large enough to carry safely the greatest possi¬ ble or probable flow, and, second, in fixing the proportion which the capacity of the reservoir may bear to the total annual run-off of the stream, so as to minimize the ratio of silt deposited to the total volume of water impounded. It may be accepted as true that the destiny of every reservoir is to be filled with silt sooner or later. If a reservoir were created on a stream carrying silt to the extent of of its volume on an average (although few actually carry so much as 1$), and the average annual flow of the stream were, for an extreme example, fifty times as great as the capacity of the reservoir, the latter would be filled and become unservice¬ able in two years, assuming that the greater portion of the silt carried was deposited in the reservoir. It would evidently, therefore, be unprofitable to construct such a reservoir unless provision were made for an immediate increase in height of dam, for diverting the river around the reservoir, which is usually impracticable, or for sluicing or dredging the silt from the reservoir, a process involving great expense. If, on the other hand, the reservoir capacity was made great enough to store rather more than the usual average flow for one year, the period of usefulness of the works would be vastly increased, and the consideration of the problem of silt disposal would be left for future generations to solve.

The importance of reservoir-construction and water-storage for irriga¬ tion was not so generally recognized in the arid region prior to about the year 1885 as it has been subsequent to that time, and it is only within a comparatively recent period that capital has been extensively enlisted in such works except for the storage of water for cities and towns. With a few prominent examples of successful achievement in that line as precedents, however, the subject of water-storage has awakened wide-spread attention, and each year it appears to be attracting deeper public interest. Capital has been slow to undertake the largest and most important works of this character, because of the difficulty of realizing immediate returns upon the investment. The development of a new section upon which water is but recently introduced, the construction of distributing canals, ditches, and pipes, the cultivation of the land and the planting of orchards—in fact the conversion of a desert to a condition of profitable productiveness, is the work of time, which cannot be begun until the irrigation-works are actually com¬ pleted, and when begun is slow of full development. Meantime, however,

IXTROD UCTION.

Vll the interest account accumulates, and often is so far in excess of possible revenues as to bring discouragement, and sometimes actual bankruptcy, before a paying basis is reached. The uncertainty of the laws of the differ¬ ent States governing water rights in reservoirs, the difficulty of establishing fixed rates for water that will be high enough to afford an adequate revenue to the capital involved and low enough to enable the farmer to pay for the water he requires and make a living while developing his farm, and the responsibilities involved in the risk fiom floods, accidents, and dry seasons, have been potent in deterring capitalists from investing in the business of storing and selling water, per se, unless it were coupled with the ownership of the lands to be irrigated, or with the domestic supply of a growing town, or with the possibilities of generating water-power.

The recent development of electrical machinery, by which power may profitably be transmitted long distances with comparatively small loss, has indirectly benefited the irrigation development of the country by adding an incentive to the construction of storage-reservoirs for the primary and more profitable purpose of generating power. Many reservoirs are being favorably considered by capitalists for the power which they will afford that would otherwise be regarded as comparatively valueless or unprofitable investments for irrigation alone. As the great bulk cf precipitation in the arid region occurs in the mountains, where it increases with some degree of uniformity with every foot of increased altitude, the mountains are coming to be regarded as indispensable to the wealth of the country, valuable not only for their precious metals, stone, and timber, but for the store of water which they are able to supply to the thirsty plains below. The mountains not only supply the water, but they usually afford the best sites for reservoirs to impound it, in ancient lake-beds, and high, cool, deep valleys, surrounded by forests; while the latter fulfil a most important function and attain a value far higher than the mere commercial one to be derived from their lumber and firewood, by serving to retard the rapid run-off of the water-supply. Forest growth is of primary importance in the preservation of the source of streams, in preventing the mountains from being washed down with destructive force to the valleys and the sea, and in creating natural reservoirs on every square mile of their surface.

That storage-reservoirs are a necessary and indispensable adjunct to irrigation develojmient, as w r ell as to the utilization of power, requires no argument to prove. That they will continue to become more and more necessary to our Western civilization is equally sure and certain; but the signs of the times seem to point to the inevitable necessity of governmental control in their construction, ownership, and administration. Those which private capital may undertake should only be permitted to be erected under the most rigid governmental supervision, to assure their absolute safety. Many reservoirs are needed for the development of the arid regions which

Vlll

INTRODUCTION.

are of too great a magnitude to be undertaken by private capital or organized individual effort. In every other country such works are undertaken by the national government. In general it may be said that the lands which would be benefited by such works in arid America belong to the govern¬ ment. To make these lands productive and capable of sustaining popula¬ tion, the government of the United States should undertake their reclamation and construct and administer the reservoirs. That such a policy will ere long be inaugurated seems inevitable. The purpose of this work is to familiarize the public with the details of construction and the general features of interest appertaining to the principal reservoirs constructed or projected in the Western States and Territories which have come within the knowledge or observation of the writer, describing in a popular way their characteristics, their water-supply, the results accomplished or sought to be accomplished by them, and the methods and materials employed in the construction of the dams which form them.

Chapter I. Page

Various types of rock-fill dams described,—The Escondido dam, faced with redwood plank—the first rock-fill dam built for irrigation storage.—Lower Otay steel-core, rock-fill dam, general description of construction.—Morena rock-fill dam, with concrete facing.—Barrett dam, under construction.—Upper Otay dam, projected and begun.—Chatsworth Park rock-fill, with concrete and masonry skin.—The Pecos Valley, N. M., type of rock-fill dams, with earth facing.—Quick¬ opening spillway gates.—Walnut Grove rock-fill dam, and its disasterous failure.

—East Canyon Creek rock-fill dam, with plate-steel center-core.—South Platte dam.—The English dam, Cal., timber-crib rock-fill.—The Bowman dam, an exist¬ ing example of earlier rock-fill construction.

CHAPTER II. Hydraulic-fill Dams. 76

Principles of dam construction by the agency of water.—San Leandro and Temescal dams, supplying Oakland, Cal., partially built by the hydraulic method.

_The Tyler, Texas, hydraulic-fill dam, the cheapest on record.—La Mesa, Cal.,

hydraulic-fill dam, and the assorting of rock and earth by the varying velocities of water.—The Lake Christine hydraulic-fill dam, San Joaquin River, Cal., in process of construction.—The filling of high trestles with earth and rock embank¬ ment by hydraulic methods on the Canadian Pacific and Northern Pacific railways, as illustrating the principles of hydraulic dam construction.—Hydraulic construc¬ tion at Seattle, Tacoma, and elsewhere.

Chapter III

Elementary principles involved.—Curved vs. straight masonry dams.—The advantages of curvature in all masonry dams as a safeguard against cracks due to extreme changes of temperature.—The' old Mission dam, erected by the Jesuit Fathers near San Diego, Cal., one of the first structures of its kind in America.—

El Molino dam.—The Sweetwater dam, its original design, construction, severe test and subsequent enlargement.—The silt problem in the Sweetwater reservoir. —The Hemet dam and the irrigation of land from Lake Hemet reservoir.—The Bear Valley dam, the slenderest dam of its height in the world.—La Grange dam, the highest overflow dam in America.—The Folsom dam, Cal., erected by

ix

X

TABLE OF CONTENTS.

PAGE

convict labor.—The San Mateo, Cal., concrete dam, the greatest mass of concrete in existence.—Run-olf of streams supplying the San Mateo and adjacent reser¬ voirs.—Pacoima submerged dam.—Agua Fria dam, Ariz., and the limited volume of underflow in streams shown by its construction.—The Seligman dam.—The Williams dam.—The Walnut Canyon dam, Ariz., and the phenomenal leakage of the reservoir behind it.—The Ash Fork, Ariz., steel dam, the only one of its type in the world.—The Lynx Creek dam, and its failure, a conspicuous example of how dams should not be built.—Concrete dams at Portland, Oregon.—The Basin Creek, Mont., masonry dam.—A masonry dam under 640-ft. head.—New Croton dam, New York, and other dams of the New York City water-supply works.— Indian River dam.—Cornell University dam and the provision made for con¬ traction cracks—Bridgeport and Wigwam dams, Conn.—The Austin dam and its recent failure.—Masonry dams in Guanajuato, Mexico.—Foreign dams of Spain, France, Belgium, Italy, Wales, Algiers, Germany, Egypt, India, China, and Australia.

Chapter IV

Ancient earth dams of Ceylon and India, of enormous dimensions.—Modern dams of India.—General principles to be observed in earth dam construction.—

The Vallejo dam.—Cuyamaca dam and reservoir and the irrigation system sup¬ plied.—Merced reservoir dam.—Buena Vista Lake dam.—Pilarcitos and San Andres dams, supplying San Francisco.—Cache la Poudre dam.—Earth dams erected by the State of Colorado.—Doubtful results of State construction of stor¬ age-reservoirs.

CHAPTER V. Naturae Reservoirs. 299

The Alpine Reservoir, Cal., formed by an earthquake.—Twin Lakes Reservoir,

Colo.—Larimer and Weld natural reservoir.—Marston Lake, supplying Denver.— Loveland basin.—The Laramie basin, Wyo.—Lake de Smet, Wyo.—Natural gravel-bed storage-reservoirs on the Los Angeles, San Gabriel and Santa Ana rivers, in Southern California.

Chapter VI

Reservoir surveys made by the U. S. Geological Survey, tables of capacity and area, and contour maps in Appendix.—Government surveys in Wyoming and Col¬ orado, reported on by Col. H. M. Chittenden, Corps of Engrs., U. S. A.—Govern¬ ment reservoir surveys on the Gila River, Arizona, to provide storage water for irrigation on the Gila River Indian Reservation.—The San Carlos, Riverside, and Buttes sites.—The Tonto Basin reservoir, Ariz., and the projected mammoth dam of masonry.—Proposed reservoirs on Rio Verde, Arizona.—Projected dam in Bear Canyon, near Tucson, Arizona, for power and irrigation.—Proposed dams and reservoirs on the Rio Grande in New Mexico and Texas.—The Elephant Butte masonry dam.—Run-off of the Rio Grande and water-supply available for irrigation.

—Proposed reservoirs in Texas.—Caimanche Lake.—Nueces reservoir.—Fria River reservoirs.—Sand Lake reservoir.—Upper Pecos reservoir-sites in New Mexico.—

TABLE OF CONTENTS.

xi

*

PAGE

Projected dam and reservoir on Rock Creek, Nev., for irrigation in the Humboldt Valley.—Lost Canyon, Colo., natural rock-till dam.—Projected reservoirs in Cali¬ fornia.—The Little Bear Valley dam, of concrete, in process of construction by the Arrowhead Reservoir Co.—Huston Flat reservoir-site, and its projected hydraulic-fill dam.—Grass Valley reservoir-site.—The projected masonry dam at Victor, Cal. on the Mojave River.—Projected reservoirs in San Diego Co.—Proposed reservoirs on Kern River, Cal.—The Manache Meadows site and the project of the Kern- Rand Reservoir and Electric Co. for power utilization.—Kern Lake reservoir-site.—

Big Meadows.—Utilization of natural lakes.—The enterprise of the Great Plains Water Co. in the Arkansas Valley, Colo., in the storage of fiood waters in enor¬ mous natural basins.

Appendix

Containing tables of reservoir areas and capacities of selections made by U. S. Geological Survey—tables of capacities of various reservoirs in service—tables of cost of reservoirs per acre-foot of reservoir capacity, etc. 385

LIST OF ILLUSTRATIONS.

1. Map of Escondido Irrigation District and System of Works. 2

2. Feeder Canal on the Side of Rodriguez Mountain, Escondido Irrigation District 3

3. Feeder Conduit of Escondido Irrigation District. 6

4. Escondido Irrigation Dam, looking north, showing Spillway. 7

5. Back of Escondido Irrigation District Dam. 9

6. Plans and Profiles of Escondido Dam... 12

7. Details of Gate of Escondido Dam. 13

8. Pick-up Weir at Head of Distributing System in Escondido Irrigation District. 14

9. Contour Map of Reservoir of Escondido Irrigation District. 16

10. Construction of Facing of Escondido Dam. 17

10a. Escondido (Cal.) Rock-fill Dam—Wooden Lining. facing page 18

106. Site of Dam, South Platte Reservoir Site—Narrowest Part. facing page 19

11. Masonry Foundation of Lower Otay Dam. 21

j- Otay (Cal.) Rock-fill Dam—Steel Core. facing pages 22, 24

12. Steel Web-plate and Anchor-trench at West End of Lower Otay Dam. 23

12a. Otay (Cal.) Rock-fill Dam—Steel Core. facing page 25

13. Crest of Lower Otay Dam, showing Web-plate of Steel embedded in Concrete.

Dam nearing Completion. 25

14. Map of Lower Otay Reservoir... 26

15. Plans of Lower Otay Reservoir. 28

16. Explosion of Great Blast at Lower Otay Rock-fill Dam. 29

17. Barrett Dam. 33

18. Morena Dam-site, looking East. 37

19. Morena Hock-fill Dam in Process of Construction. Showing Top of Toe-wall

above the Water-line. 39

20 Morena Rock-fill Dam, showing a Portion of Toe-wall under Construction. 40

21. Reservoirs near San Diego, California. . 41

22. Upper Otay Dam, Foundation Masonry. 42

23. Sketch of Reconstruction of Chatswortli Park Rock-fill Dam. 44

24. Castlewood Dam, Colorado ; Plan, Sections, and Elevation. 46

24a. View of Castlewood Dam, Colorado, during Construction, looking North

246 View of Castlewood Dam and Reservoir, Colorado... facing page 47

25. Sketch-map of Dam at Head of Pecos Canal. 47

n/ 26. Lake Avalon Dam. Rock-fill in Process of Construction. 48

27. Lake Avalon Dam, Pecos River, New Mexico. Showing the Crest of Com¬

pleted Dam and Spillway Discharging. 49

28. Canal Headgates, Lake Avalon Dam. 50

29. Quick-opening Gates in Spillway of Lake Avalon Reservoir, Pecos Valley, New

Mexico.... 51

xiii

XIV

LIST OF ILLUSTRATIONS.

30. Sections of Lake Avalon and Lake McMillan Rock-fill and Earth Dams, Pecos

Valley, New Mexico. 51

31. Sketch-map of Pecos Valley Canals. .... 52

32. Map of Pecos Valley, New Mexico, showing Location of Reservoirs and Canals 55

33. Cross-section and Elevation of Walnut Grove Dam, Arizona. 59

34. View' of Walnut Grove Dam, Arizona. 60

35. East Canyon Creek Dam, LTtah. Rock-fill with Steel Core. 65

36. Balanced Valve, used for Reservoir Outlet, South Platte Rock-fill Dam. 68

37. South Platte Rock-fill Dam. View of False Work and Bridge over the Dam-site 69

37a. Site of Dam, South Plate Reservoir Site—Above. .facing page 71

v/ 38. Map of Reservoir formed by Rock-fill Dam on South Platte River, Colorado ... 72

38a. Plan and Cross-section of the Bowman Dam. facing page 74

385. Plan and Cross-section of the Fordyce Rock-fill Dam, California.. .facing page 75

39. Plans and Cross-sections of San Leandro and Temescal Dams. 78

40. Hydraulic-fill Dam at Tyler, Texas, showing Delivery-pipe supported on a

Grade-line, carrying Material to Opposite Side, and Spillway Cut made by sluicing the Earth into Base of Dam. 79

41. Hydraulic Sluicing for building Dam at Tyler, Texas. 81

42. Hydraulic-fill Dam, at Tyler, Texas, in Process of Construction. 85

43. View of Finished Dam and Wastew-ay of La Mesa Reservoir. 87

43a. La Mesa (Cal.) Dam in Course of Construction by the Hydraulic Process

44. La Mesa Reservoir. Beginning of the Construction of Hydraulic-fill Dam. 91

45. Details of Outlet-gate and Well-culvert of La Mesa Dam. 93

46. Construction of Hydraulic Dam, La Mesa Reservoir, illustrating the Method of

Suspending Pipes. 95

47. Cross-section of La Mesa Dam. 97

48. La Mesa Hydraulic-fill Dam, showing Pipe Discharging Material on the Dam.. 98

48a. View of Lake Christine Dam-site, showing Outlines of Hydraulic-fill Dam

485. View of Lake Christine Dam-site, San Joaquin River, near Fresno, California, where a Hydraulic-fill Dam is in Process of Construction. facing page 99

49. Hydraulic Sluicing, Canadian Pacific Railway. View' of Pit, and Hydraulic

Giant at Work.. 101

50. Hydraulic Fills, partially completed, at Mountain Creek, B. C., Canadian Pa¬

cific Railw'ay. 107

51. Hydraulic Filling of High Trestle at Mountain Creek, B. C., on Canadian Pa¬

cific Railway, near View of Dump. 109

52. Northern Pacific Railway. Bridge 190. Ill

53. Northern Pacific Railway. Bridge 189, Cascade Mountains. 112

54. Northern Pacific Railway, Hydraulic-fill Construction. View in Pit showing

Hydraulic Giant in Action. 113

55. Northern Pacific Railway, Bridge 184. Hydraulic Filling in Progress. 114

56. Comparison of Profiles of Zola, Sweetwater, and Bear Valley Dams. 120

57. Old Mission Dam, near San Diego, Cal. The First Irrigation Dam built in the

United States. 123

58. Original Sw'eetwater Dam as completed to the Sixty-foot Contour. 127

59. Elevations and Sections of Sweetwater Dam. 129

60. Face of Sweetwater Dam in 1899. After Two Years of Drouth. 130

61. Details of Tower of Sweetw'ater Dam. 132

62. Sweetwater Dam as finished, April, 1888. 133

LIST OF ILLUSTRATIONS.

XV

63. Sweetwater Dam daring tlie Great Flood of January 17, 1895. 135

63a. Sweetwater (Cal.) Masonry Dam. .facing page 137

64. Spillway of Sweetwater Dam, seen from Below. 139

65., Sweetwater Dam, showing New Apron of Spillway and Protecting Spur-walls

on Pipe-line . 141

66. Repairing and Increasing the Height of the Parapet of Sweetwater Dam. 143

67. Plan of Sweetwater Dam. 145

68. Profile and Sectional View and Plan of Wasteway Tunnel, Sweetwater Dam... 145

69. Details of Sweetwater Dam.146

70. Sweetwater Dam, showing Head of Outlet Tunnel and Spillway. 147

71. Map showing Location of Lake Hemet, the Main Conduit, and Irrigated Lands. 153

72. Hemet Dam, Riverside County, California. 155

73. Hemet Dam as finished, showing the Spillway Ridge south of the Dam. 157

74. Contour Map of the Lake Hemet Reservoir. 159

75. Hemet Dam, Riverside County, California. 160

76. Hemet Dam Construction Plant. 161

76a. Lake Hemet (Cal.) Masonry Dam. facing page 162

v 77. Cross-section of Bear Valley Dam. 165

78. Plan and Elevation of Bear Valley Dam. 165

79. Bear Valley Dam, looking south, toward Spillway. 167

80. Spillway of Bear Valley Dam, with Flashboard Gates. 169

f 81. Base of New Rock-fill Dam, Below the Bear Valley Dam. 171

82. Map of Bear Valley Reservoir. 175

82a. Plan of La Grange Dam, California... 177

825. Profile of La Grange Dam, California. 177

83. Upper Face of La Grange Dam. 178

84. Lower Face of La Grange Dam. 179

85. La Grange Dam, California, during Constuction—finishing the Crest. 181

j- La Grange Dam, California.181, 183

88. La Grange Dam, California, during Flood. 183

89. Map showing Location of Folsom Dam and the Main Canal. 185

90. Plan, Cross-section, and Elevation of Weir and Headworks of Folsom Canal... 186

91. American River Dam at Folsom. 187

92. Hvdraulic Jacks for raising Shutter on Folsom Dam. 189

93. View of Masonry Dam on American River, California, at the Folsom State

Prison, showing Canal Head-gates. 191

94. Plant for Mixing and Handling Concrete at San Mateo Dam. >... 193

95. Construction of Intake of San Mateo Dam.195

V 96. Moulds for Concrete Blocks, San Mateo Dam. 197

97. Roughening Surface of Concrete Blocks to receive Fresh Cement, at San Mateo

98. San Mateo Dam being Inspected by American Society of Civil Engineers in

99. Plans and Sections of San Mateo Dam and Map of Crystal Springs Reservoir

100. The Newell Curve .204

101. Excavation of Trench for Pacoima Subterranean Dam.207

102. View of Flood passing over Pacoima Subterranean Dam.209

103. Plan and Profile of Pacoima Dam.211

104. Measuring-box.212

XVI

LIST OF ILLUSTRATIONS.

FIGURE

105. Cross-sections of Agua Fria Diverting-dam and Storage-reservoir Dam, Arizona. 100. Foundations of West Channel of Agua Fria Diverting-dam.

107. Diverting-dam of the Agua Fria.

108. Submerged Storage- and Diverting-dam, near Kingman, Arizona.

109. Seligman Dam, Arizona..

110. View of Upper Face of Seligman Dam during Construction.

111. Section and Profile of Seligman Dam.

112. Ash Fork, Arizona, Steel Dam, View of Steel Construction from Lower Side...

113. Ash Fork, Steel Dam, showing Frame ready to receive Plates.

114. Ash Fork Reservoir.

115. Walnut Canyon Dam, Arizona.

11G. Section and Profile of Walnut Canyon Dam, Arizona..

117. Lynx Creek Dam, Arizona, after Rupture by Flood. View from below_

118. Lynx Creek Dam, Arizona. Section showing Facing Walls, and Concrete Heart¬

ing. .

PAGE

220 221

226 227

120 . 121 . 122 .

131. 131«

Inner Face of Concrete Dam at Portland, Oregon. 231

Exterior View of Reservoir Dams at Portland, Oregon. 233

Reservoir No. 2, Portland, Oregon, showing Aerating Fountain 125 feet high.. 235 Masonry Dam under 640-foot Head, the Greatest Recorded Water-pressure on

Masonry.... .

Austin Dam and Power-house, Texas. 243

Austin Dam, during Flood of April 7, 1900, and immediately before the Break 245

Austin Dam, Texas. View taken during Flood, a few Minutes after the Break.

View after Subsidence of Flood of April 7, 1900, showing Section of Masonry

moved bodily Down-stream. .

Upper Dam at Guanajuato, Mexico.. 249

Lower Dam, or “Preslade la Olla” Guanajuato, Mexico. frontispiece

The Ekruk Tank, Bombay, Plan and Details.

Cross-section of the Ashti Dam, India.

View of Cuyamaca Dam and Outlet Tower. 282

Masonry Diverting-dam of the San Diego Flume Co., California. 283

Plan and Elevation of Diverting-dam of San Diego Flume Co., California. 286

Sample of High Trestle Construction on San Diego Flume, California.287

. Map showing Location of Merced Reservoir, California. 290

View of Yosemite Reservoir, Merced, California.* ’ ” 291

Reservoir of South Antelope Valley Irrigation Company. gQl

Map of Little Rock Creek Irrigation District. 390

\ iew of a Corner of the Basin of Alpine Reservoir before Work was Begun_ 305

Details of I unnel-outlet of the Alpine Reservoir.. 304

Arkansas River Basin. Twin Lakes Reservoir-site. facing page 307

Detail’s of Outlets for Twin Lakes, Colo. 303

The ‘‘Devil’s Gate,” Sweetwater River, Wyoming. 317

Contour Map of Buttes Reservoir-site, Gila River, Arizona. .facing page 323

Longitudinal Section of Buttes Dam-site, Gila River, Arizona. 393

Section of Proposed Rock-til! Dam at the Buttes, Gila River, Arizona 324

Section of Proposed Buttes Dam through Spillway, showing End Wall of Rock

. 324

Plan of Buttes Dam-site, showing Location selected for Rock-fill Dam facing page 325

Plan of Riverside Dam-site, Gila River, Arizona, showing Location selected for Proposed Masonry Dam...

LIST OF ILLUSTRATIONS.

XVil

>/ 146. Contour Map of San Carlos Reservoir-site, Gila River, Arizona... . facing page 327

147. Longitudinal Profile of San Carlos Dam-site, showing Elevation of Proposed

Masonry Dam. 326

148. Contour Plan of San Carlos Dam-site, showing Location selected for Proposed

Masonry Dam. facing page 329

149. Maximum Profile of Proposed San Carlos Dam of Masonry. 327

149a. San Carlos Dam-site, looking Down-stream. .facing page 329

150. Section of San Carlos Dam through one of the Outlet Towers, illustrating

Arrangement of Control. 328

151. Details of Outlet Tower and Gates. San Carlos Dam, Gila River, Arizona.329

152. San Carlos Dam, Arizona, Section througu Spillway.329

152a. San Carlos Dam-site, looking Down stream ...331

153. Boring Apparatus. 331

154. View of San Carlos Dam-site, Gila River, Arizona. 333

154a. View of Left Abutment Wall, San Carlos Dam-site, showing Dip of Lime¬ stone . 335

V 155. View of the Buttes Dam-site, looking Down-stream.335

155a. Buttes Dam-site, looking Up-stream from Upper Toe. 337

156. Buttes Dam-site, looking Up-stream ; Proposed Quarries on Left ; Spillway on

Left Center of Field. 337

157. View of Riverside Dam-site, Gila River, Arizona. 339

158. Plan of Tonto Dam. 340

159. Sections of Dam and Canyon of Tonto Reservoir.341

160. Map of Tonto Basin Reservoir, showing Elevations of Ten Cross-sections of the

Reservoirs. 342

161. Tonto Basin Dam-site, Salt River, Arizona, looking Down-stream. 343

162. Dam-site on Salt River below Mouth of Tonto Creek.345

163. Map of Gila and Salt River Valleys, showing Existing and Proposed Irrigation

Works. facing page 346

164. Map of Salt River Valley, showing Canals Constructed and Proposed facing page 347

165. Map of Site of Horseshoe Reservoir, on Verde River. 347

166. Map of Lower Portion of McDowell Reservoir. 349

167. Elephant Butte Dam on Rio Grande, above El Paso, Texas. Plan and Section

of Dam-site, Profile of Dam, and Plan of Outlets. 355

168. Map of Elephant Butte Reservoir on the Rio Grande. 356

169. Diverting-dara near Fort Selden, Texas, in Process of Construction. 357

170. Wood-stave Pipes, laid under Bed of the Rio Grande.360

171. Map of Rock Creek Reservoir, Canal Lands, and Lands to be Irrigated.364

172. Plan of Dam-site and Reservoir-site, Rock Creek, Nevada. 365

173. Sketch of Longitudinal Section of Lost Canyon Natural Dam. 366

174. Sketch of Cross-section at Upper End of Lost Canyon Natural Dam. 367

174a. Comparison of Dams of the System of the Arrowhead Reservoir Company.... 369