This book is a development of class-room and lecture notes prepared by the author for use in his classes at the University of Illinois. He has found such notes necessary, since among the many books dealing with sewerage and sewage treatment he has found none suitable as a text-book designed to cover the entire subject. The need for a single book of the character described has been expressed by engineers in practice, and by students and teachers for use in the class-room. This book has been prepared to meet both these needs. It is hoped that the searching questions propounded by students in using the original notes, and the suggestions and criticisms of engineers and teachers who have read the manuscript, have resulted in a text which can be readily understood.
The ground covered includes an exposition of the principles and methods for the designing, construction and maintenance of sewerage works, and also of the treatment of sewage. In covering so wide a field the author has deemed it necessary to include some chapters which might equally well appear in works on other branches of engineering, such as the chapter on Pumps and Pumping Stations. Special stress has been laid on the fundamentals of the subject rather than the details of practice, although illustrations have been drawn freely from practical work. The quotation of expert opinions which may be in controversy, or the citation of examples of different methods of accomplishing the same thing, has been avoided when possible in order to simplify explanations and to avoid confusing the beginner.
The work is to some extent a compilation of notes and quotations which have been collected by the author during years of study and teaching the subject. Credit has been given wherever due, and at the same time references have pointed out the original sources whenever possible. These references, which have been supplemented by brief bibliographies at the end of certain chapters, will be useful to the student and engineer interested in further study. Occasionally the original reference has been lost or the phraseology of a quotation has been so altered by class-room use, as to make it impossible to trace the original source, so that in some few instances full credit may be lacking.
The author is indebted to many of his friends for their criticisms and suggestions in the preparation of the manuscript; but he desires particularly to acknowledge the assistance of Professor A. N. Talbot, Professor of Municipal and Sanitary Engineering at the University of Illinois, and of Professor M. L. Enger, Professor of Mechanics and Hydraulics at the University of Illinois, in the entire work; also that of Mr. T. D. Pitts, Principal Assistant Engineer of the Baltimore Sewerage Commission during the construction of the Baltimore sewers, for his suggestions on the first half of the book; and to Mr. Paul Hansen, consulting engineer, of Chicago, and to Mr. Langdon Pearse, Sanitary Engineer of the Sanitary District of Chicago, for their help on the section covering the treatment of sewage; and to Professor Edward Bartow, Professor of Chemistry at the University of Iowa, for his review of the chapter on Activated Sludge; in general his thanks are due to all others who have furnished suggestions, illustrations, or quotations, acknowledgments of which have been included in the text.
H. E. B.
Urbana, Illinois, 1922.
TABLE OF CONTENTS
| CHAPTER I | |
| Introduction | |
| PAGES | |
|---|---|
| 1. Sewerage and the Sanitary Engineer. 2. Historical. 3. Methods of Collection. 4. Methods of Disposal. 5. Methods of Treatment. 6. Definitions. | [1]–8 |
| CHAPTER II | |
| Work Preliminary to Design | |
| 7. Division of Work. 8. Preliminary. 9. Estimate of cost. Methods of Financing. 10. Bond Issues. 11. Special Assessment. 12. General Taxation. 13. Private Capital. Preliminary Work. 14. Preparing for Design. 15. Underground Surveys. 16. Borings. | [9]–23 |
| CHAPTER III | |
| Quantity of Sewage | |
| 17. Dry Weather Flow. 18. Methods for Predicting Population. 19. Extent of Prediction. 20. Sources of Information on Population. 21. Density of Population. 22. Changes in Area. 23. Relation between Population and Sewage Flow. 24. Character of District. 25. Fluctuations in Rate of Sewage Flow. 26. Effect of Ground Water. 27. Résumé of Method for Determination of Quantity of Dry weather Sewage. Quantity of Storm Water. 28. The Rational Method. 29. Rate of Rainfall. 30. Time of Concentration. 31. Character of Surface. 32. Empirical Formulas. 33. Extent and Intensity of Storms. | [24]–50 |
| CHAPTER IV | |
| Hydraulics of Sewers | |
| 34. Principles. 35. Formulas. 36. Solution of Formulas. 37. Use of Diagrams. 38. Flow in Circular Pipes Partly Full. 39. Sections Other than Circular. 40. Non-Uniform Flow. | [51]–77 |
| CHAPTER V | |
| Design of Sewerage Systems | |
| 41. The Plan. 42. Preliminary Map. 43. Layout of the Separate System. 44. Location and Numbering of Manholes. 45. Drainage Areas. 46. Quantity of Sewage. 47. Surface Profile. 48. Slope and Diameter of Sewers. 49. The Sewer Profile. Design of a Storm-water Sewer System. 50. Planning the System. 51. Location of Street Inlets. 52. Drainage Areas. 53. Computation of Flood Flow by McMath Formula. 54. Computation of Flood Flow by Rational Method. | [78]–98 |
| CHAPTER VI | |
| Appurtenances | |
| 55. General. 56. Manholes. 57. Lampholes. 58. Street Inlets. 59. Catch-basins. 60. Grease Traps. 61. Flush-tanks. 62. Siphons. 63. Regulators. 64. Junctions. 65. Outlets. 66. Foundations. 67. Underdrains. | [99]–126 |
| CHAPTER VII | |
| Pumps and Pumping Stations | |
| 68. Need. 69. Reliability. 70. Equipment. 71. The Building. 72. Capacity of Pumps. 73. Capacity of Receiving Well. 74. Types of Pumping Machinery. 75. Sizes and Descriptions of Pumps. 76. Definitions of Duties and Efficiency. 77. Details of Centrifugal Pumps. 78. Centrifugal Pump Characteristics. 79. Setting of Centrifugal Pumps. 80. Steam Pumps and Pumping Engines. 81. Steam Turbines. 82. Steam Boilers. 83. Air Ejectors. 84. Electric Motors. 85. Internal Combustion Engines. 86. Selection of Pumping Machinery. 87. Costs of Pumping Machinery. 88. Cost Comparisons of Different Designs. 89. Number and Capacity of Pumping Units. | [127]–163 |
| CHAPTER VIII | |
| Materials for Sewers | |
| 90. Materials. 91. Vitrified Clay Pipe. 92. Cement and Concrete Pipe. 93. Proportioning of Concrete. 94. Waterproofing of Concrete. 95. Mixing and Placing Concrete. 96. Sewer Brick. 97. Vitrified Clay Sewer Block. 98. Cast Iron, Steel, and Wood. | [164]–193 |
| CHAPTER IX | |
| Design of the Sewer Ring | |
| 99. Stresses in Buried Pipe. 100. Design of Steel Pipe. 101. Design of Wood Stave Pipe. 102. External Loads on Buried Pipe. 103. Stresses in Circular Ring. 104. Analysis of Sewer Arches. 105. Reinforced Concrete Sewer Design. | [194]–210 |
| CHAPTER X | |
| Contracts and Specifications | |
| 106. Importance of the Subject. 107. Scope of the Subject. 108. Types of Contracts. 109. The Agreement. 110. The Advertisement. 111. Information and Instructions for Bidders. 112. Proposal. 113. General Specifications. 114. Technical Specifications. 115. Special Specifications. 116. The Contract. 117. The Bond. | [211]–232 |
| CHAPTER XI | |
| Construction | |
| 118. Elements. Work of the Engineer. 119. Duties. 120. Inspection. 121. Interpretation of Contract. 122. Unexpected Situations. 123. Cost Data and Estimates. 124. Progress Reports. 125. Records. Excavation. 126. Specifications. 127. Hand Excavation. 128. Machine Excavation. 129. Types of Machines. 130. Continuous Bucket Excavators. 131. Cableway and Trestle Excavators. 132. Tower Cableways. 133. Steam Shovels. 134. Drag Line and Bucket Excavators. 135. Excavation in Quicksand. 136. Pumping and Drainage. 137. Trench Pump. 138. Diaphragm Pump. 139. Jet Pump. 140. Steam Vacuum Pumps. 141. Centrifugal and Reciprocating Pumps. 142. Well Points. 143. Rock Excavation. 144. Power Drilling. 145. Steam or Air for Power. 146. Depth of Drill Hole. 147. Diameter of Drill Hole. 148. Spacing of Drill Holes. Sheeting and Bracing. 149. Purposes and Types. 150. Stay Bracing. 151. Skeleton Sheeting. 152. Poling Boards. 153. Box Sheeting. 154. Vertical Sheeting. 155. Pulling Wood Sheeting. 156. Earth Pressures. 157. Design of Sheeting and Bracing. 158. Steel Sheet Piling. Line and Grade. 159. Locating the Trench. 160. Final Line and Grade. 161. Transferring Grade and Line to the Pipe. 162. Line and Grade in Tunnel. Tunnelling. 163. Depth. 164. Shafts. 165. Timbering. 166. Shields. 167. Tunnel Machines. 168. Rock Tunnels. 169. Ventilation. 170. Compressed Air. Explosives and Blasting. 171. Requirements. 172. Types of Explosives. 173. Permissible Explosives. 174. Strength. 175. Fuses and Detonators. 176. Care in Handling. 177. Priming, Loading, and Firing. 178. Quantity of Explosive. Pipe Sewers. 179. The Trench Bottom. 180. Laying Pipe. 181. Joints. 182. Labor and Progress. Brick and Block Sewers. 183. The Invert. 184. The Arch. 185. Block Sewers. 186. Organization. 187. Rate of Progress. Concrete Sewers. 188. Construction in Open Cut. 189. Construction in Tunnels. 190. Materials for Forms. 191. Design of Forms. 192. Wooden Forms. 193. Steel-lined Wooden Forms. 194. Steel Forms. 195. Reinforcement. 196. Cost of Concrete Sewers. Backfilling. 197. Method. | [233]–331 |
| CHAPTER XII | |
| Maintenance of Sewers | |
| 198. Work Involved. 199. Causes of Troubles. 200. Inspection. 201. Repairs. 202. Cleaning of Sewers. 203. Flushing Sewers. 204. Cleaning Catch-basins. 205. Protection of Sewers. 206. Explosions in Sewers. 207. Valuation of Sewers. | [332]–351 |
| CHAPTER XIII | |
| Composition and Properties of Sewage | |
| 208. Physical Characteristics. 209. Chemical Composition. 210. Significance of Chemical Constituents. 211. Sewage Bacteria. 212. Organic Life in Sewage. 213. Decomposition of Sewage. 214. The Nitrogen Cycle. 215. Plankton and Macroscopic Organisms. 216. Variations in the Quality of Sewage. 217. Sewage Disposal. 218. Methods of Sewage Treatment. | [352]–371 |
| CHAPTER XIV | |
| Disposal by Dilution | |
| 219. Definition. 220. Conditions Required for Success. 221. Self-purification of Running Streams. 222. Self-purification of Lakes. 223. Dilution in Salt Water. 224. Quantity of Diluting Water Needed. 225. Governmental Control. 226. Preliminary Treatment. 227. Preliminary Investigations. | [372]–382 |
| CHAPTER XV | |
| Screening and Sedimentation | |
| 228. Purpose. 229. Types of Screens. 230. Sizes of Openings. 231. Design of Fixed and Movable Screens. Plain Sedimentation. 232. Theory of Sedimentation. 233. Types of Sedimentation Basins. 234. Limiting Velocities. 235. Quantity and Character of Grit. 236. Dimensions of Grit Chambers. 237. Existing Grit Chambers. 238. Number of Grit Chambers. 239. Quantity and Characteristics of Sludge from Plain Sedimentation. 240. Dimensions of Sedimentation Basins. Chemical Precipitation. 241. The Process. 242. Chemicals. 243. Preparation and Addition of Chemicals. 244. Results. | [383]–409 |
| CHAPTER XVI | |
| Septicization | |
| 245. The Process. 246. The Septic Tank. 247. Results of Septic Action. 248. Design of Septic Tanks. 249. Imhoff Tanks. 250. Design of Imhoff Tanks. 251. Imhoff Tank Results. 252. Status of Imhoff Tanks. 253. Operation of Imhoff Tanks. 254. Other Tanks. | [410]–430 |
| CHAPTER XVII | |
| Filtration and Irrigation | |
| 255. Theory. 256. The Contact Bed. 257. The Trickling Filter. 258. Intermittent Sand Filter. 259. Cost of Filtration. Irrigation. 260. The Process. 261. Status. 262. Preparation and Operation. 263. Sanitary Aspects. 264. The Crop. | [431]–464 |
| CHAPTER XVIII | |
| Activated Sludge | |
| 265. The Process. 266. Composition. 267. Advantages and Disadvantages. 268. Historical. 269. Aëration Tank. 270. Sedimentation Tank. 271. Reaëration Tank. 272. Air Distribution. 273. Obtaining Activated Sludge. 274. Cost. | [465]–479 |
| CHAPTER XIX | |
| Acid Precipitation, Lime and Electricity, and Disinfection | |
| 275. The Miles Acid Process. Electrolytic Treatment. 276. The Process. Disinfection. 277. Disinfection of Sewage. | [482]–493 |
| CHAPTER XX | |
| Sludge | |
| 278. Methods of Disposal. 279. Lagooning. 280. Dilution. 281. Burial. 282. Drying. | [495]–505 |
| CHAPTER XXI | |
| Automatic Dosing Devices | |
| 283. Types. 284. Operation. 285. Three Alternating Siphons. 286. Four or More Alternating Siphons. 287. Timed Siphons. 288. Multiple Alternating and Timed Siphons. | [506]–512 |
SEWERAGE AND SEWAGE TREATMENT