Page 10 - Water Engineering Hydraulics, Distribution and Treatment

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Contents
7.8
Practical Applications of
Mains
Computer-Aided Water Supply System
270
232
Analysis
9.2.7
Chlordane and Heptachlor at
Problems/Questions
a Housing Authority
233
Boiler Water Entered High
240
References
9.2.8
School Drinking Water
Car Wash Water in the Street
9.2.9
272
8
Water Main
Pumping, Storage, and Dual Water
241
Systems
9.2.10
Health Problems Due to
Cross-Connection in an
275
Office Building
Pumps and Pumping Stations
241
8.1
9.3 9.2.6 Propane Gas in the Water 271 271
Theory of Backflow and
8.2 Pump Characteristics 241
Backsiphonage 276
8.2.1 Power Requirements and
9.3.1 Water Pressure 276
Efficiencies of Pumps 244
9.3.2 Siphon Theory 277
8.2.2 Cavitation 245
9.3.3 Backflow 280
8.2.3 Performance Characteristics 246
9.4 Methods and Devices for the
8.3 Service Storage 248
Prevention of Backflow and
8.3.1 Equalizing, or Operating,
Backsiphonage 280
Storage 248
9.4.1 Air Gap 281
8.3.2 Fire Reserve 249
9.4.2 Barometric Loops 281
8.3.3 Emergency Reserve 249
9.4.3 Atmospheric Vacuum
8.3.4 Total Storage 249
Breakers 281
8.4 Location of Storage 251
9.4.4 Hose Bib Vacuum Breakers 282
8.5 Elevation of Storage 251
9.4.5 Pressure Vacuum Breakers 283
8.6 Types of Distributing Reservoirs 251
9.4.6 Double Check Valves with an
8.7 Dual Water Supply Systems 257
Intermediate Atmospheric
8.7.1 Background 258
Vent 283
8.7.2 The Nature of the Problems with
9.4.7 Double Check Valves 284
Drinking Water Quality 258
9.4.8 Double Check Detector
8.7.3 The Pipes in the Distribution
Check 284
Systems 258
9.4.9 Residential Dual Check 285
8.7.4 Biofilms and the Problems They
9.5 Reduced Pressure Principle Backflow
Cause 259
Preventer 285
8.7.5 The Proposed System 259
9.6 Administration of a Cross-Connection
8.8 Raw Water Intake Structures and Raw
Control Program 289
Water Pumping Wells 260
9.6.1 Responsibility 289
Problems/Questions 262
9.6.2 Dedicated Line 290
References 266
9.6.3 Method of Action 290
9.7 Pressure and Leakage Tests of Water
Mains 291
9 Cross-Connection Control 267
9.7.1 Preparation for Pressure and
Leakage Tests 291
9.1 Introduction 267 9.7.2 Pressure and Leakage Tests 292
9.2 Public Health Significance of Problems/Questions 293
Cross-Connections 268 References 295
9.2.1 Human Blood in the Water
System 268
9.2.2 Sodium Hydroxide in the Water 10 Water Quality Characteristics and
Main 268 Drinking Water Standards 297
9.2.3 Heating System Antifreeze in
Potable Water 268
10.1 Objectives of Water-Quality
9.2.4 Salt Water Pumped into
Management 297
Freshwater Line 269
10.2 Natural Available Water Resources 297
9.2.5 Paraquat in the Water System 269