(Principles and practices of water supply operations series) American Water Works Association-Water transmission and distribution _ student workbook-American Water Works Association (2010).pdf

Principles and Practices of Water Supply Operations WSO Water Transmission and Distribution Student Workbook

Water Transmission and Distribution

Student Workbook AWWA is the authoritative resource for knowledge, information, and advocacy to improve the quality and supply of water in North America and beyond. AWWA is the largest organization of water professionals in the world, advancing public health, safety, and welfare by uniting the efforts of the full spectrum of the water community. Through our collective strength, we become better stewards of water for the greatest good of people and the environment.

1P-4E-5.5C-1967-8/10-EB

1967 Water T&D Workbook cover.indd 1

Advocacy Communications Conferences Education and Training Science and Technology Sections

The Authoritative Resource on Safe Water ®

7/29/2010 3:53:40 PM

Water Transmission and Distribution Student Workbook

Water Transmission and Distribution Student Workbook Principles and Practices of Water Supply Operations Series Copyright © 2006, 2010 American Water Works Association. All rights reserved. No part of this publication may be reproduced or transmitted in any form or by any means, electronic or mechanical, including photocopy, recording, or any information or retrieval system, except in the form of brief excerpts or quotations for review purposes, without the written permission of the publisher. Disclaimer The authors, contributors, editors, and publisher do not assume responsibility for the validity of the content or any consequences of their use. In no event will AWWA be liable for direct, indirect, special, incidental, or consequential damages arising out of the use of information presented in this book. In particular, AWWA will not be responsible for any costs, including, but not limited to, those incurred as a result of lost revenue. In no event shall AWWA’s liability exceed the amount paid for the purchase of this book. Technical Editor Nancy McTigue Project Manager: Melissa Valentine Production: TIPS Technical Publishing, Inc. Cover Design: Cheryl Armstrong

ISBN 10: 1-58321-800-9 ISBN 13: 978-1-58321-800-6 Printed in the United States of America American Water Works Association 6666 West Quincy Avenue Denver, CO 80235 303.794.7711

Water Transmission and Distribution Student Workbook Principles and Practices of Water Supply Operations Series

Contents Contents v Foreword vii Acknowledgments ix Introduction: Using Your Student Workbook xi Chapter 1

Introduction to Water Distribution Systems

1

Chapter 2

Pipe Systems and Piping

Chapter 3

Water Storage

Chapter 4

Pumping Stations and Pumps

Chapter 5

Hydraulics of Water Distribution Systems 29

Chapter 6

Valves

Chapter 7

Fire Hydrants

Chapter 8

Motors and Engines

Chapter 9

Instrumentation and Control 57

7

15 21

35 41 49

Chapter 10 Water Meters 63 Chapter 11 Backflow Prevention and Cross-Connection Control 69 Chapter 12 Water Main Installation

75

Chapter 13 Backfilling, Main Testing, and Installation Safety Chapter 14 System Operations

87

Chapter 15 Water Services 95 Chapter 16 Information Management 101 Chapter 17 System Security and Emergency Response Chapter 18 Public Relations

v

115

107

81

Foreword This workbook is designed for use with the text Water Transmission and Distribution in the series Principles and Practices of Water Supply Operations, fourth edition. This edition provides detailed information on the technology and information of commonly used practices for potable water treatment. Other volumes in the series are •

Water Sources

•

Water Treatment

•

Water Quality

•

Basic Science Concepts and Applications

The workbook provides assignments, review questions, and a convenient method for keeping organized notes of important points as the text is reviewed. It is designed for use in either classroom or independent study. Basic Science Concepts and Applications is a reference handbook that is a companion to all the other text books. It contains basic reviews of mathematics, hydraulics, chemistry, and electricity fundamental to water utility operation, as well as explanations and examples of many specific water system operating problems. A special thanks to Nancy McTigue for the revision of this workbook.

vii

Acknowledgments The student workbooks have been added to the WSO series in conjunction with the fourth edition updating of the WSO texts. The author of this Student Workbook is Nancy McTigue. Special thanks to Larry Mays, author of the revision of the text book, and Bill Lauer, AWWA Senior Technical Manager, for their review of this workbook.

ix

Introduction: Using Your Student Workbook This Student Workbook is provided to assist you in studying the basic principles of water distribution systems. If you carefully maintain your own personal workbook with notes and supplemental information, you will likely reference it throughout your water utility career.

FORMAT This workbook provides the following sections for each chapter of the text: •

Objectives. This is a listing of some of the major concepts that you should be able to identify and explain when you have completed study of the chapter. You should preview the list at the beginning of study to assess what will be covered. You should then review it again when you have completed study of the chapter to see if you adequately understand the listed concepts.

•

Reading Assignments. A list is provided indicating the chapters and sections from Water Transmission and Distribution and other texts that should be read in conjunction with the study of the chapter.

•

Other Assignments. If you are attending a class, this space can be used to make a record of additional reading and study assignments made by the instructor. If you are using this workbook for self-study, you can make notes for future reference on additional sources of information.

•

Class Notes. Space has been provided for you to keep notes of points you feel are important as you read the text or of points made by the instructor during class discussions.

•

Review Questions. The review questions are intended to emphasize some of the important concepts in the chapter.

•

Study Problems. A few problems are provided to be used for additional study.

•

Additional Notes. Each chapter concludes with an extra page for note taking.

TEXTS AND REFERENCES It will be necessary for you to have copies of both Water Transmission and Distribution and Basic Science Concepts and Applications available while studying the subject. You should also have access to the other volumes in the series Principles and Practices of Water Supply Operations because there are some references to them in the reading assignments. If the copies you are using belong to your water utility or someone else, it is best not to mark or highlight in the books. Your notes on important points can instead be made in the workbook. A list of supplementary sources of information is provided at the end of each chapter in the text. You should try to make use of some of them, particularly if you have a special interest in certain subjects. For example, if you are presently working at a water treatment

xi

xii

WSO: Water Transmission and Distribution Student Workbook

facility, you will probably want to know more about the particular types of treatment or operating problems experienced by your utility. The supplementary reading list is, of course, current only as of the publication of the text. Many additional handbooks, manuals, and articles are published yearly. If you have a special interest in obtaining the latest information on a subject, you may contact the American Water Works Association (AWWA) and some of the other publishers and information sources for their current publications list. If you have access to a file of back issues of the Journal AWWA and Opflow, you will find that an index of all articles for the previous year is listed in each December issue. The “Water Library” section of the www.awwa.org website also has a searchable database of Journal of the American Water Works Association and Opflow articles, conference proceedings and AWWA Standards. If you are presently working for a water utility, you probably have access to old editions and copies of some texts that are no longer in print. You will find it is helpful to look through these books and read about subjects you are studying, using this workbook. Sometimes, there may be more detail, or subjects may be presented in a different way in another text. You must be aware, though, that water treatment technology and state and federal regulations have changed greatly in recent years, so some information in an older text will no longer be valid. The principal publications that are frequently referenced and will be particularly useful to have on hand during study of Water Transmission and Distribution include: •

Water Quality and Treatment. 6th ed. 2010. New York: McGraw-Hill and American Water Works Association (available from AWWA).

•

Manual of Water Utility Operations. 8th ed. 1988. Austin, Texas: Texas Water Utilities.

•

Manual of Instruction for Water Treatment Plant Operators. 1975. Albany, N.Y.: New York State Department of Health.

•

Back copies of the Journal AWWA and Opflow.

USE OF THE WORKBOOK If you are using this workbook in conjunction with class instruction, you are urged to keep a loose-leaf notebook for supplementary sheets distributed by the instructor, filed in the order in which the subjects are studied. When your notes are carefully kept in order, they provide an excellent personal information source for later review and reference. The review questions are designed to highlight some of the major points of each chapter. You should reread sections covered by the review questions until you can completely answer the questions. The instructor will then review the answers during a class period to make sure everyone understands the subject and has provided the correct answers. Your instructor usually will also provide supplemental assignments and furnish handout material for each chapter. When the length of class meetings is limited, some chapters will be broken into segments and covered during two or more meetings. The workbook can also be used for individual study. Notes should be made of important points as the text and references are read, and the review questions should be answered completely to ensure that the full significance of important points is understood.

STATE AND FEDERAL REGULATIONS Many aspects of water treatment and distribution system operation are now directed and regulated by federal regulations. A review of federal regulations in effect at the time the second edition of this volume was published is provided in Water Quality (another volume in this series). But many changes are expected within coming years.

Introduction: Using Your Student Workbook

xiii

Although the states are generally required to enact regulations that are as stringent as the federal requirements, they may, at times, vary, be more stringent, or include additional requirements. It is therefore important that you obtain a reference copy of the latest state drinking water regulations for the state in which you are working. Applicable sections of the regulations should then be reviewed in conjunction with your study of each chapter.

QUIZZES AND EXAMINATIONS If you are attending training classes, the instructor will probably give you a few quizzes during the course. These are important to you in indicating whether you are adequately learning the material being presented; they are also important to the instructor to determine if the material is being properly presented. If you are studying this subject in preparation for taking a state certification examination, it is particularly important that you become comfortable in taking exams of the type used by the state. If you would like more review and practice in answering questions of the type used on certification exams, it is suggested that you obtain the AWWA publication Operator Certification Study Guide, 6th ed., Denver, Colo.: American Water Works Association.

Good Luck in Your Water Utility Career!

CHAPTER 1

Introduction to Water Distribution Systems OBJECTIVES After completing study of this chapter, you should be able to understand: •

the purpose of drinking water distribution systems

•

the types of public water systems, categorized by water source

•

the components of distribution systems

READING ASSIGNMENTS 1.

Water Transmission and Distribution: Read chapter 1, Introduction to Water Distribution Systems.

2.

State public water supply regulations: Read sections relating to required state approval of plans and specifications for water distribution system construction.

OTHER ASSIGNMENTS

1

2


CLASS NOTES 1.

System purpose:

2.

Types of systems:

3.

System planning issues:

4.

Supply and distribution system components:

Chapter 1: Introduction to Water Distribution Systems

REVIEW QUESTIONS 1.

What are two purposes of drinking water distribution systems?

2.

What is a “well field” and why is it sometimes installed?

3.

Why are increasing numbers of public water systems purchasing their water from another utility?

4.

What special features are typically included in a purchased water source system?

5.

What is a rural water system?

3

4


6.

How do local conditions affect the design of distribution systems? Name two of these local considerations:

7.

What kind of local policy decisions could affect new system development or expansion?

8.

Name six functional components of a conventional water supply system : •

•

•

•

•

• 9.

Name three components of a distribution system: • • •

Chapter 1: Introduction to Water Distribution Systems

5

STUDY PROBLEMS 1.

You work for a public water system that uses surface water as a source. A housing development near your distribution system would like you to extend your distribution system to accommodate the houses in the development. Currently, the houses use a communal well for their water supply. The home owners have asked if their distribution system can be directly connected to your public water system. For your manager, put together a list of issues that would need to be resolved before the decision could be made.

6


ADDITIONAL NOTES

CHAPTER 2

Pipe Systems and Piping OBJECTIVES After completing study of this chapter, you should be able to understand: •

the common configurations used in distribution system design

•

the principal considerations involved in sizing water mains

•

considerations that must be made when piping materials are selected

•

the purpose of AWWA and ANSI/NSF standards

•

the four general types of piping used in water systems

•

general characteristics of commonly used pipe materials

•

principal advantages and disadvantages of each type of pipe

•

types of joints and fittings primarily used with each type of pipe


2.

Water Transmission and Distribution: •

Read chapter 2, Pipe Systems and Piping.

•

Read appendix A, Specifications and Approval of Treatment Chemicals and System Components.

State public water supply regulations: Read sections relating to required state approval of plans and specifications for water distribution system construction.

OTHER ASSIGNMENTS

7

8


CLASS NOTES 1.

System planning:

2.

System layout:

3.

Sizing mains:

4.

Fire flow requirements:

5.

Material selection:

6.

Pipe uses:

Chapter 2: Pipe Systems and Piping

7.

Gray cast-iron pipe:

8.

Ductile-iron pipe:

9.

Steel pipe:

10. Asbestos–cement pipe:

11. PVC and other plastic pipe:

12. Concrete pipe:

9

10


REVIEW QUESTIONS 1.

What type of distribution system configuration is not recommended? Why?

2.

Explain what determines the selection of main sizes.

3.

What is the minimum main size recommended by the fire insurance underwriters?

4.

What is a network analysis?


11

5.

What do AWWA standards define? What materials are covered by ANSI/NSF 61?

6.

Explain what is meant by the C value of a pipe.

7.

List seven unusual pipe installation conditions that might have a bearing on the type of pipe used for a particular installation. • • • • • • •

8.

What are transmission lines?

12


9.

Identify five types of piping material commonly installed today in water distribution systems. • • • • •

10. List some advantages and disadvantages of ductile-iron pipe.

11. List six common types of joints used with ductile-iron pipe, and describe the conditions under which each may be used. •

•

•

•

•

•

12. List some advantages and disadvantages of PVC pipe.


13

STUDY PROBLEMS 1.

Suppose your utility serves a population of 10,000 people. To meet increased demand in a new service area, a main extension program is being considered. The soil in the area ranges from hardpan to cobbles. Prepare statements supporting your recommendations for •

the selection of the best type of pipe to use

•

the minimum size of main that should be installed

2.

The present water source for your community (population 50,000) is no longer adequate. You are considering running a main to a point 5 mi (8 km) away where a new well field can be established. Assume this main would not have to go through any other communities. Contact contractors in your area for the approximate cost per foot of installing a main for various types of pipe, assuming soil and terrain conditions for your part of the country. Prepare a brief report of the considerations that must be made and your recommendations for the pipeline.

3.

Contact distribution system operators at several public water systems in the area and determine the following information: •

If there are old water mains in the system: —How old are the oldest mains? —What type of pipe is it? —What problems have there been with the pipes?

•

For mains installed in recent years: —What type of pipe is presently being installed? —If the type is different than the old pipe, why was a change made? —If a different type of pipe is now being used, what have the advantages and disadvantages been? From this information, compile some conclusions for your area on the following:

•

the effect of local water quality and weather conditions on the selection of pipe materials

•

the changes being made by water systems in the type of pipe that is being used

•

reasons the water systems are changing or not changing the type of pipe being used

14


ADDITIONAL NOTES

CHAPTER 3

Water Storage OBJECTIVES After completing study of this chapter, you should be able to understand: •

the principal reasons for storing water in the distribution system

•

the difference between operating storage and emergency storage requirements

•

common construction features and accessory devices for water storage tanks

•

key factors that must be considered to select the proper size and location for a water reservoir

•

important points in the operation and maintenance of water storage facilities


Water Transmission and Distribution: Read chapter 3, Water Storage.

2.

State drinking water regulations: Read sections relating to requirements for the type and amount of storage that must be provided.

OTHER ASSIGNMENTS

15

16


CLASS NOTES 1.

Water storage requirements:

2.

Types of treated-water storage facilities:

3.

Locations of distribution storage systems:

4.

Water storage facility equipment:

5.

Operation and maintenance of water storage facilities:

6.

Water storage facility safety:

Chapter 3: Water Storage

17

REVIEW QUESTIONS 1.

Identify nine reasons for providing water storage within a distribution system. • • • • • • • • •

2.

What is the difference between operating storage and emergency storage?

3.

What are the advantages and disadvantages of elevated tanks, standpipes, and ground-level tanks?

4.

Describe the operation and intended application of hydropneumatic storage.

18


5.

Materials of construction used for drinking water reservoirs must be in compliance with which standards?

6.

What is the benefit of having many smaller storage tanks in a distribution system instead of one large tank?

7.

List three types of piping found in every water tank. • • •

8.

After disinfection, what must be done before a water storage tank can be placed back in service?

9.

List five safety precautions that must be observed during work inside storage tanks. • • • • •

Chapter 3: Water Storage

19

STUDY PROBLEMS 1.

Obtain a map of a local community and locate all water storage facilities on it. Prepare a report discussing the advantages and disadvantages of each of the locations regarding elevation, position in relation to population centers and sources of supply, hydraulics, and acceptability to the public.

2.

Prepare a report discussing cold-weather problems that can be experienced with elevated storage tanks, as well as what should be done to minimize the problems.

20


ADDITIONAL NOTES

CHAPTER 4

Pumping Stations and Pumps OBJECTIVES After completing study of this chapter, you should be able to understand: •

the operating principles of common types of velocity and positive-displacement pumps

•

general operating procedure for centrifugal pumps and the reasons for these procedures

•

the regular preventive maintenance procedures required for centrifugal pumps

•

the purpose and function of the principal parts of centrifugal pumps


Water Transmission and Distribution: Read chapter 4, Pumping Stations and Pumps.

OTHER ASSIGNMENTS

21

22


CLASS NOTES 1.

Types of pump stations:

2.

Pump curves for pump stations:

3.

Types of pumps:

4.

Operation of centrifugal pumps:

5.

Centrifugal pump maintenance:

6.

Record keeping:

7.

Pump safety:

Chapter 4: Pumping Stations and Pumps

23

REVIEW QUESTIONS 1.

What is the purpose of a booster pump station?

2.

What two types of piping are found in a pump station?

3.

What is the purpose of surge (pressure) relief valves in the discharge piping of a pump station?

4.

What are the two basic categories of pumps used in water supply operations? What are the principal water supply uses of each type? •

•

5.

What is the basic operating principle of a velocity pump?

24


6.

Identify one unique safety feature that velocity pumps have over positive-displacement pumps.

7.

What is a multistage centrifugal pump? What effect does the design have on discharge pressure and flow volume?

8.

What are the two pump and motor arrangements commonly used for vertical turbine well pumps? • •

9.

What type of vertical turbine pump is commonly used as an in-line booster pump?

10. Describe the two main parts of a jet pump. • • 11. What is the purpose of a foot valve installed on the suction pipe to a centrifugal pump?


25

12. What is the function of the wear rings in the centrifugal pumps of the closed-impeller design? What is the function of lantern rings?

13. Describe the two common types of seals used to control leakage between the pump shaft and the casing. •

•

14. What are the four steps that should be followed in greasing pump bearings? • • • •

26


STUDY PROBLEMS 1.

Outline the basic steps that should be considered during installation of a vertical turbine pump that will pump from a wet well.

2.

Visit the pump house at a local water system and record information on two or three different makes or models of pumps that are in use. If possible, obtain a copy of the manufacturer’s pump curve for each pump. Obtain the following information for each unit: •

pump data: design type, name of manufacturer, model number, date of installation, types of bearings, types of seals, and so on

•

driving motor horsepower rating

•

installation: inlet and outlet piping sizes, types of valves and valve operators, increases in pipe sizes near the unit, and so on

•

observations: suction and outlet pressures during operation, amount of water leaking from the gland, pump noise, relative bearing temperature (i.e., hot or cool), noticeable vibration, and so on From the collected data, prepare a brief report on each pump unit.

•

Refer to the pump curve. At what theoretical efficiency is the pump operating?

•

Does the pump appear to need repair or replacement?

•

Does the water system maintain good records of its equipment and of the maintenance and repair work performed?


ADDITIONAL NOTES

27

CHAPTER 5

Hydraulics of Water Distribution Systems OBJECTIVES After completing study of this chapter, you should be able to understand: •

how to calculate the flow of water in a pipe

•

how the variables in the Hazen –Williams are determined

•

the components and interactions of system hydraulics

•

the capabilities and use of network analysis


Water Transmission and Distribution: Read chapter 5, Hydraulics of Water Distribution Systems.

OTHER ASSIGNMENTS

29

30


CLASS NOTES 1.

Pipe flow calculations:

2.

C-values:

3.

Minor head loss:

4.

Water demand:

5.

Hydraulic dead end:

6.

Water age:

7.

Network analysis:

8.

Water hammer:

Chapter 5: Hydraulics of Water Distribution Systems

REVIEW QUESTIONS 1.

What is a C-value? What is a typical C-value for a new unlined cast iron pipe?

2.

What is the definition of friction slope (Sf)?

3.

What causes minor head loss in a water distribution network?

4.

What is the minor loss coefficient associated with a 45° elbow?

5.

What does a diurnal flow curve show?

31

32


6.

Why should dead ends be avoided in a water distribution system?

7.

What factors can affect water age?

8.

What impact does a pipe break have on the distribution system’s hydraulic performance?

9.

What applications can EPANET be used for in distribution system analysis?

10. What causes water hammer in a water distribution system? What measures can be taken to avoid water hammers in the distribution system?

Chapter 5: Hydraulics of Water Distribution Systems

33

STUDY PROBLEM 1.

You have been asked by your manager to investigate implementing a hydraulic model to describe your utility’s distribution system. Research what software models are available in the public domain for free (EPANET) or for purchase. Determine what data your utility will have to assemble to put into one of these software models. Contact a nearby utility to find out if that utility uses a hydraulic model and if so, what benefits they have found using the model.

34


ADDITIONAL NOTES

CHAPTER 6

Valves OBJECTIVES After completing study of this chapter, you should be able to understand: •

the conditions under which different types of valves are installed in the distribution system

•

common types of valves and components

•

the purpose of a valve exercise program and how one should be conducted

•

recommended inspection checks and maintenance that should be performed on valves

•

the various types of valve operators used in water systems

•

records that should be kept on distribution system valves


Water Transmission and Distribution: Read chapter 6, Valves.

OTHER ASSIGNMENTS

35

36


CLASS NOTES 1.

Uses of water utility valves:

2.

Types of water utility valves:

3.

Valve operation:

4.

Valve storage:

5.

Valve joints:

6.

Valve boxes and vaults:

7.

Valve records:

Chapter 6: Valves

REVIEW QUESTIONS 1.

List nine uses for valves in a water distribution system. • • • • • • • • •

2.

Should gate valves be used for throttling flow? Why or why not?

3.

Describe how an air-and-vacuum relief valve works.

4.

What is the primary purpose of a bypass valve?

37

38


5.

When is an inserting valve installed in a water main?

6.

What are the two principal uses of large check valves in a water system? • •

7.

List three types of power operators for valves. • • •

8.

List the three most common types of joints used to install large water system valves. • • •

9.

What is the main purpose of valve boxes and vaults?

10. What factors must be kept in mind concerning drainage for valve vaults?

Chapter 6: Valves

39

STUDY PROBLEMS 1.

You are a distribution system operator and the director of public works has asked you to recommend the types of valves to install on a new 14-in. (350-mm) transmission main. The required types of valves will need to •

isolate the main from connecting mains

•

throttle flow in the main

•

prevent backflow into the main from a brewery What are your recommendations and why?

2.

You and a co-worker have been asked to shut off a valve in a vault. The worker enters the vault without any safety equipment and collapses. What should you do? What should have been done to ensure his or her safety?

3.

Diagram or describe how you, by using landmarks, would pinpoint the location of a valve located in a residential district.

4.

You have just been employed as chief operator for a town serving 8,500 people. You soon discover there are no valve records. Describe how you would go about locating the valves in the distribution system, and describe the types of records you would establish.

40


ADDITIONAL NOTES

CHAPTER 7

Fire Hydrants OBJECTIVES After completing study of this chapter, you should be able to understand: •

the various uses of hydrants in a distribution system

•

the difference between dry-barrel and wet-barrel hydrants

•

principal components of dry-barrel and wet-barrel hydrants

•

proper procedures for installing, operating, inspecting, and maintaining hydrants

•

the proper way to perform a hydrant flow test

•

the information that should be recorded when fire hydrants are installed, inspected, and repaired

•

safety precautions that should be observed during fire hydrant flushing and testing


Water Transmission and Distribution: Read chapter 7, Fire Hydrants.

OTHER ASSIGNMENTS

41

42


CLASS NOTES 1.

Fire hydrant uses:

2.

Types of fire hydrants:

3.

Hydrant parts:

4.

Inspection and installation:

5.

Operation and maintenance:

6.

Hydrant records:

7.

Hydrant safety:

Chapter 7: Fire Hydrants

REVIEW QUESTIONS 1.

List four of the common authorized uses for fire hydrants, other than for fire protection. • • • •

2.

List four reasons why strict controls should be exercised over hydrant uses. • • • •

3.

How can operation of a fire hydrant cause water quality problems?

4.

Explain the principal difference between a dry-barrel and wet-barrel hydrant.

5.

In relation to the street, what direction should the pumper nozzle be pointed?

43

44


6.

List two ways hydrants can be protected from damage by traffic. • •

7.

List three important installation details that should be observed during the installation of dry-barrel hydrants. • • •

8.

What is the purpose of a color-coding scheme for hydrant tops or caps?

9.

Why is the speed at which hydrant valves are operated important?

10. Name three preventive measures that should be taken in cold-climate areas to ensure that hydrants will remain operable during the winter. • • • 11. List three items of information about the distribution system that can be obtained from hydrant flow tests. • • •


45

12. Why is it important to record every hydrant inspection with an entry of the date and condition of the hydrant?

13. List three items of information that should be included on a hydrant record form. • • • 14. Name five safety precautions that should be taken during hydrant flushing and testing to prevent injury to personnel and the public and to minimize damage to property. • • • • •

46


STUDY PROBLEMS 1.

You have just taken over as operator of the distribution system for a community that presently has no hydrant records. Obtain a copy of a blank hydrant record card from a neighboring water utility, or make a copy of the example in the text. Using an existing hydrant in the area, complete the card with information on the hydrant, a sketch, and location data. Try to make the record as complete as possible. You may estimate the hydrant age based on the hydrant model or by finding out when the main was installed. You may estimate the buried depth by measuring the depth of the auxiliary valve.

2.

Under the supervision of the instructor or an experienced operator, conduct a hydrant flow test and determine the flow available from the test hydrant at 20 psi (140 kPa) residual pressure.

3.

Under the supervision of the instructor or an experienced operator, provide a complete inspection of an installed hydrant and mark the appropriate information on a record form.


ADDITIONAL NOTES

47

CHAPTER 8

Motors and Engines OBJECTIVES After completing study of this chapter, you should be able to understand: •

the types of electric motors used to power water system equipment

•

the principal types of motor control equipment used

•

methods of improving the efficiency of electrically driven pumps

•

the principal parts that must be periodically maintained or repaired in electric motors and control equipment

•

principal types of combustion engines used to power water system equipment

•

important points in the operation and maintenance of engines


Water Transmission and Distribution: Read chapter 8, Motors and Engines.

OTHER ASSIGNMENTS

49

50


CLASS NOTES 1.

Electricity terminology review:

2.

Principles of electric motor operation:

3.

Single-phase and three-phase motors:

4.

Electric motor construction:

5.

Motor control equipment:

6.

Improving the efficiency of electrically driven pumps:

Chapter 8: Motors and Engines

7.

Maintenance of electric motors:

8.

Types of combustion engines:

9.

Operation and maintenance of internal-combustion engines:

10. Motor and engine records:

11. Motor and engine safety:

51

52


REVIEW QUESTIONS 1.

What is the relationship between volts, amps, and ohms that is expressed in Ohm’s law?

2.

What is the maximum synchronous speed that a motor can operate at on 60-Hz power?

3.

When do most electric motors draw the most current?

4.

What can happen when a fuse blows on one leg of a three-phase circuit?

5.

What are three major ways of reducing power costs where electrically driven pumps are used? • • •

6.

What is the value of listening to a pump or motor and laying a hand on the unit as it operates?


7.

What effect could over lubrication of motor bearings have?

8.

Why should emery cloth not be used around electrical equipment?

9.

Name five common fuels for internal-combustion engines.

53

• • • • • 10. List the type of information that should be recorded on a basic data card for pumping equipment.

11. What is the first rule of safety for repairing electrical devices?

54


STUDY PROBLEMS 1.

Outline a basic scheme for the periodic inspection and maintenance program of a pump house that has four electric-motor-driven pumps and a diesel generator unit.

2.

Review the stand-by power units installed at a local water system. Determine what the system’s minimum, average, and maximum daily and hourly flow rates are, as well as the system’s history of power outages. Prepare a brief report describing how successful the system’s equipment is in meeting customer water demands during power outages, and suggest what equipment could be changed or added if the present equipment is not considered adequate.


ADDITIONAL NOTES

55

CHAPTER 9

Instrumentation and Control OBJECTIVES After completing study of this chapter, you should be able to understand: •

the various types of primary and secondary instrumentation used in water system operation

•

the method of operation of common sensors

•

how a basic telemetry system works

•

ways in which manual, semiautomatic, and automatic control systems can be arranged to operate

•

how supervisory control and data acquisition (SCADA) systems can be used in water system operation

•

general requirements for maintenance of instruments and control equipment


Water Transmission and Distribution: Read chapter 9, Instrumentation and Control.

2.

State drinking water regulations: Read sections pertaining to equipment automation.

OTHER ASSIGNMENTS

57

58


CLASS NOTES 1.

Primary instrumentation:

2.

Secondary instrumentation and telemetering:

3.

Control systems:

4.

Supervisory control and data acquisition:

5.

Operation and maintenance:

Chapter 9: Instrumentation and Control

59

REVIEW QUESTIONS 1.

List six general types of primary instruments (sensors) commonly found in a water distribution instrumentation system. • • • • • •

2.

Electrical measurements are commonly explained by comparison to similar variables used to describe hydraulic conditions. Explain how voltage, current, and resistance are similar to conditions measured in a water main.

3.

What is the fourth commonly measured electrical variable not discussed in the previous question? What units is it measured in? What does it indicate?

4.

What is the purpose of secondary instruments?

60


5.

What is the difference between an analog and a digital indicator?

6.

When is a telemetry system required?

7.

Explain the four methods that can be used to obtain information or to control more than one system over a single transmission channel. • • • •

8.

Distinguish among manual, automatic, and semiautomatic control systems.

9.

What does SCADA stand for?

Chapter 9: Instrumentation and Control

61

STUDY PROBLEMS 1.

Select a single control station or pumping station on a local water system and trace the signal path for a single simple instrument, such as a pressure or flow sensor. Identify each of the components of the instruments and record the model name and manufacturer. Using the utility’s repair manuals or manufacturer’s literature, investigate the internal construction of each component and identify the function of each of the parts.

2.

Determine what types of telemetry systems a local water utility uses, and for what functions. •

Are the equipment and the transmission channel owned or leased by the utility?

•

Who is responsible for repairs?

•

If a radio or microwave system is used, what repairs can be performed by a technician who does not hold Federal Communications Commission (FCC) certification as a radio repair person?

•

At the central control point for the distribution system, identify which systems are automatic, manual, and semiautomatic.

•

What alarms are installed in case of system failure?

•

What backup systems are available if the central control station or telemetry lines fail?

62


ADDITIONAL NOTES

CHAPTER 10

Water Meters OBJECTIVES After completing study of this chapter, you should be able to understand: •

the importance of metering water entering the distribution system as well as water used by customers

•

the basic operating principles of meters commonly used in water systems

•

factors that influence the type and size of meter used for various purposes

•

conditions that influence where meters are located

•

records that should be maintained on meters


Water Transmission and Distribution: Read chapter 10, Water Meters.

OTHER ASSIGNMENTS

63

64


CLASS NOTES 1.

Customer water meters:

2.

Customer meter installation:

3.

Meter reading:

4.

Meter testing, maintenance, and repair:

5.

Mainline metering:

6.

Weirs:

7.

Metering flumes:

8.

Metering safety:

Chapter 10: Water Meters

65

REVIEW QUESTIONS 1.

What are two reasons for metering water customers? • •

2.

Name the two types of positive displacement meters commonly used on customer water services. • •

3.

Compound meters are generally used under what conditions?

4.

List four factors that must be considered to select the correct size of meter. • • • •

5.

List 10 requirements for an acceptable meter installation. • • • • • • • • • •

66


6.

List four reasons a manifold (or battery) meter installation is used in place of a single large meter. • • • •

7.

What is a meter yoke? What are some of the advantages of using one?

8.

List three basic elements in a meter test. • • •

9.

What is the principle of operation of a venturi meter?

10. Explain the need for maintaining electrical continuity around the meter during removal.

Chapter 10: Water Meters

67

STUDY PROBLEMS 1.

Determine if your state has adopted requirements for the frequency of testing meters, and if so, what those requirements are. Check with managers of several local utilities and find out what their policy is for meter testing and/or replacement. At the same time, determine the water source and treatment provided by each system. Summarize the information, highlighting any apparent relationship between the frequency of testing and other factors such as water quality, size of the system, and the cost of treated water used by the system. How do the state requirements for frequency of water meter testing compare with the frequency suggested by the American Water Works Association (AWWA)?

68


ADDITIONAL NOTES

CHAPTER 11

Backflow Prevention and Cross-Connection Control OBJECTIVES After completing study of this chapter, you should be able to understand: •

public health hazards that are created by cross-connections

•

factors that allow backflow and backsiphonage to occur

•

types of installations or facilities that are likely to have cross-connections

•

appropriate backflow-prevention devices that should be used based on the degree of hazard involved

•

steps required to establish and administer a cross-connection control program


Water Transmission and Distribution: Read chapter 11, Backflow Prevention and Cross-Connection Control.

2.

State drinking water regulations: Review requirements for public water systems to have a cross-connection control program.

OTHER ASSIGNMENTS

69

70


CLASS NOTES 1.

Cross-connection terminology:

2.

Where cross-connections occur:

3.

Types of cross-connections:

4.

Public health significance of cross-connections:

5.

Backflow control methods and devices:

6.

Cross-connection control programs:

7.

Records and reports:

Chapter 11: Backflow Prevention and Cross-Connection Control

REVIEW QUESTIONS 1.

Define a cross-connection.

2.

Explain what is meant by backsiphonage and back pressure.

3.

List four situations that can cause negative pressure in a potable water supply. • • • •

4.

List six waterborne diseases that are known to have occurred as a result of cross-connections. • • • • • •

5.

What is the most reliable backflow-prevention method?

71

72


6.

Is a single check valve positive protection against backflow? Why or why not?

7.

How often should a reduced-pressure-zone backflow preventer be tested?

8.

In what position should an atmospheric vacuum breaker be installed relative to a shutoff valve? Why?

9.

How does a vacuum breaker prevent backsiphonage?

10. List seven elements that are essential to implement and operate a cross-connection control program successfully. • • • • • • •

Chapter 11: Backflow Prevention and Cross-Connection Control

73

STUDY PROBLEMS 1.

Your city has just annexed a subdivision where homes will be provided water by your water utility, but the homes originally had private wells and septic systems. After the hookups are completed, the weather turns very dry and water demand increases. You notice that some water samples collected near the new subdivision are showing high coliform counts. The local health officer informs you that she is receiving numerous complaints of stomach disorders and illness. Describe what you would do to investigate this situation, and include an explanation as to the most likely cause of the problem and how it can be remedied.

2.

A new hospital is being built in your city, and the director of public works has asked you to recommend the cross-connection control devices for both the water connection to the hospital and at locations within the building. Prepare a report outlining your recommendations.

3.

Describe the cross-connection control program in your community. If your community does not have a program, describe features of a program you would propose.

74


ADDITIONAL NOTES

CHAPTER 12

Water Main Installation OBJECTIVES After completing study of this chapter, you should be able to understand: •

how pipes and fittings should be handled and prepared for installation

•

methods of excavation for water main installation

•

safety precautions that should be observed during trenching and pipe installation, and methods of preventing trench-wall failure

•

procedures to be followed in laying pipe

•

methods of making connections to existing mains

•

the importance of blocking and anchoring mains against movement and the common restraint methods that are used


Water Transmission and Distribution: Read chapter12, Water Main Installation.

OTHER ASSIGNMENTS

75

76


CLASS NOTES 1.

Pipe shipment:

2.

Pipe handling:

3.

Excavation:

4.

Laying pipe:

Chapter 12: Water Main Installation

REVIEW QUESTIONS 1.

Why should pipe be inspected before and during unloading?

2.

How should pipe be unloaded?

3.

List nine important points to be considered when pipe is to be strung at a jobsite. • • • • • • • • •

4.

What eight factors usually determine the depth and width of a trench? • • • • • • • •

77

78


5.

Why should wide trenches be avoided?

6.

Name four danger signs that indicate potential trench failure. • • • •

7.

What is the angle of repose of soil and why is it important?

8.

List five typical causes of trench cave-ins. • • • • •

9.

Why is the proper placement of bedding material important?

10. Why must joint materials and pipe ends be kept clean?

11. Explain why thrust blocks and anchors are important. Where should they be used?

Chapter 12: Water Main Installation

79

STUDY PROBLEM 1.

You have just been employed to supervise the installation of a mile of new 8-in. (200-mm) polyvinyl chloride (PVC) water main that will service a newly annexed subdivision. Outline the steps you would take from delivery of the pipe up to the time the trench is ready for backfilling to ensure proper and safe installation of the pipe.

80


ADDITIONAL NOTES

CHAPTER 13

Backfilling, Main Testing, and Installation Safety OBJECTIVES After completing study of this chapter, you should be able to understand: •

proper methods of backfilling and compacting the backfill in an excavation

•

procedures in pressure and leak testing of new water mains

•

methods of flushing and disinfecting newly constructed or repaired water mains

•

restoration of structures and vegetation following construction

•

safety precautions that must be followed on a construction site to protect workers and the public


Water Transmission and Distribution: Read chapter 13, Backfilling, Main Testing, and Installation Safety.

2.

State public water supply regulations: •

Read sections applying to required leakage and bacteriological testing of water mains.

•

Read sections applying to water utility safety.

OTHER ASSIGNMENTS

81

82


CLASS NOTES 1.

Backfilling:

2.

Pressure and leak testing:

3.

Flushing and disinfection:

4.

Final inspection:

5.

Site restoration:

6.

Water main installation safety:

Chapter 13: Backfilling, Main Testing, and Installation Safety

83

REVIEW QUESTIONS 1.

List three methods that can be used to compact backfill material. • • •

2.

Explain what steps should be followed after pipe is installed but before a new pipeline is placed in service.

3.

List three methods of disinfecting water mains and briefly explain how each method works. •

•

•

4.

What is the usual procedure followed if a laboratory reports the results of the bacteriological test of a new main as “positive”?

5.

Why is it useful to take photographs or videotapes of a jobsite before construction?

84


6.

What are the four basic rules for lifting heavy objects by hand? • • • •

7.

What are two basic rules for working with a crane? • •

8.

List four items of commonly used personal protective gear that should be worn during construction. • • • •

9.

When should metal hard hats not be worn?

10. Name three safety precautions that should be taken when mains in traffic areas are being repaired. • • • 11. Why is it unwise to hurry unduly under emergency conditions?

Chapter 13: Backfilling, Main Testing, and Installation Safety

85

STUDY PROBLEMS 1.

You are the supervisor of a crew of eight workers who are about to start a small construction project that will consist of installing one block of 6-in. (150-mm) water main in a residential area. You have a small backhoe, an end loader, a portable air compressor, and a dump truck available to do the work. The soil in the area is only nominally stable. A few days before the job is to begin, you must list all of the safety procedures that must be considered both before and during the construction. Compile the list into the following categories: •

personal safety equipment that each person on the job should have

•

other safety equipment that you must be sure is available on the construction site when the job begins

•

instructions on proper safety procedures that you want to emphasize in a meeting with employees on the day the job is started

86


ADDITIONAL NOTES

CHAPTER 14

System Operations OBJECTIVES After completing study of this chapter, you should be able to understand: •

the importance and techniques for maintaining distribution system water quality

•

the practices and procedures to ensure system reliability resulting in acceptable pressure at all times and providing adequate flow for all distribution system uses


Water Transmission and Distribution: Read chapter 14, System Operations.

2.

State drinking water regulations:

3.

•

Read sections on requirements for collecting distribution system samples for analysis.

•

Read sections relating to maintaining a specified pressure in the distribution system.

ANSI/AWWA G200, Standard for Distribution System Operation and Management, AWWA.

OTHER ASSIGNMENTS

87

88


CLASS NOTES 1.

Water quality monitoring—routine and nonroutine:

2.

System design for water quality enhancement—pipe network and storage facilities:

3.

Operations and maintenance practices to maintain water quality:

4.

•

Controlling water age

•

Maintaining positive pressure

•

Controlling direction and velocity of flow

Flushing and cleaning:

Chapter 14: System Operations

5.

Lining water mains:

6.

Controlling internal corrosion:

7.

Distribution system inspection:

8.

Leak detection and water loss control:

9.

External pipeline corrosion:

89

90


REVIEW QUESTIONS 1.

What are five general steps that lead to optimized water quality in the distribution system? • • • • •

2.

What are three major components of a distribution system sampling plan? • • •

3.

List some system design considerations for both pipelines and storage facilities that could affect water quality.

4.

What are three issues to consider when operating a distribution system to maintain water quality? • • •

5.

How do you determine the flow required to perform water main flushing to remove sediment? List three precautions to take before beginning a flushing procedure.


6.

91

List five methods that may be used under various circumstances for cleaning water mains. • • • • •

7.

What are some of the consequences of corrosive water and list some ways to reduce internal pipeline corrosion.

8.

List at least two ways of detecting leaks. What are five main tasks in a distribution system water audit?

9.

List at least five factors that affect external pipeline corrosion. • • • • •

92


STUDY PROBLEMS 1.

Obtain a water plat (portion of a water system pipeline map) showing mains, valves, and hydrants for a small water system in your area. Develop a plan to perform directional flushing to effectively improve water quality in any areas of low water usage.

2.

Using the same map, organize a plan to conduct a leak detection survey using electronic equipment.

3.

Obtain a water plat that contains at least one water storage facility. Develop an operational strategy to keep the water fresh within this facility.


ADDITIONAL NOTES

93

CHAPTER 15

Water Services OBJECTIVES After completing study of this chapter, you should be able to understand: •

what is meant by a service connection

•

the components that make up a typical residential connection

•

the principal factors that govern the size of water service lines

•

factors that should be evaluated in the selection of pipe material used for a service connection

•

the different types and sizes of connections (taps) used to connect service lines

•

the use of corporation stops and the different types available

•

the method of operating the equipment used in making service taps

•

the need for keeping good records of water service installations


Water Transmission and Distribution: Read chapter 15, Water Services.

2.

State drinking water regulations: Read sections relating to the Lead and Copper Rule requirements.

OTHER ASSIGNMENTS

95

96


CLASS NOTES 1.

Meter locations:

2.

Service line sizes, materials, and equipment:

3.

Water service taps:

4.

Leaks and breaks:

5.

Thawing:

6.

Service line responsibility:

7.

Service line records:

Chapter 15: Water Services

97

REVIEW QUESTIONS 1.

What is the purpose of water service lines?

2.

Why is it a good policy to eliminate lead water services from the system whenever possible?

3.

What is a possible problem when an iron service pipe is connected to a brass curb stop?

4.

What is the most common type of inlet thread on a corporation stop? What is the major advantage of this type of thread?

5.

What is the function of a curb stop?

6.

What are two advantages of a wet tap?

98


7.

When should a service clamp be used?

8.

Explain the difference between a wet and dry tap.

9.

What two precautions are recommended before a utility undertakes the thawing of customer water services? • •

10. List eight points of information that should be recorded after a tap is made, but before the excavation is backfilled. • • • • • • • •

Chapter 15: Water Services

99

STUDY PROBLEMS 1.

Part of your system has copper service lines attached to ductile-iron mains. The system has just expanded into a new service area that has PVC mains and high-molecular-weight polyethylene service lines. All mains are 6 in. (150 mm) in diameter. Discuss the type of corporation stop and tapping procedures you would recommend for each situation.

2.

Contact two or more water utilities in your area and determine what types of materials they are presently using for water services, how deep they require the pipe to be laid, and other details. From this information, draw a cross-sectional sketch of a typical service, showing details for each system. Comment on the possible reasons for differences in the practices of different systems.

100


ADDITIONAL NOTES

CHAPTER 16

Information Management OBJECTIVES After completing study of this chapter, you should be able to understand: •

typical uses of computers in water system information management

•

the importance of maintaining system maps, drawings, and records

•

examples of maps, drawings, and records commonly used in distribution system operations, as well as their purposes

•

records that should be maintained for water distribution system equipment


Water Transmission and Distribution: Read chapter 16, Information Management.

2.

State drinking water regulations: Review sections relating to (1) reports that must be submitted to the state on distribution system operations and (2) requirements for records that water systems must maintain on their equipment and facilities.

OTHER ASSIGNMENTS

101

102


CLASS NOTES 1.

Computers:

2.

Maps and records:

3.

Maintenance management:

4.

Other major information systems:

Chapter 16: Information Management

103

REVIEW QUESTIONS 1.

List the four broad categories of water utility applications of computers. • • • •

2.

Identify the type of map that provides a clear picture of the entire distribution system.

3.

What is the name of the mapped record that provides a detailed picture of a portion of the distribution system?

4.

Identify two methods of showing the mapped locations of valves and hydrants. • •

5.

What are plan and profile drawings?

6.

What mapped record is often made up in reduced-scale reproductions for ease of handling in the field?

104


7.

Identify three types of distribution system card records that are typically maintained and the basic information each contains. • • •

8.

What is included in an automated mapping/facility management/geographic information system (AM/FM/GIS)? What is the objective of an AM/FM/GIS system in a water utility?

9.

Name five items that would typically be included in distribution system statistical records. What information would each report contain? • • • • •

10. Name five points of information typically included on a work order. • • • • • 11. Explain the need for maintaining a file on technical information.

Chapter 16: Information Management

105

STUDY PROBLEMS 1.

You have just been appointed chief operator for a water system with 4,000 service connections. You learn that there are no maps or records of the system’s facilities. Describe the types of maps and records you would initiate and how you would obtain the necessary information on existing facilities to start compiling the maps and records.

2.

Examine the comprehensive map for a local water system to determine the system’s largest and smallest mains. What purpose do the largest mains serve? Do the smallest mains adversely affect customer service or fire protection to areas of the system? If so, what methods could be used to correct the situation?

106


ADDITIONAL NOTES

CHAPTER 17

System Security and Emergency Response OBJECTIVES After completing study of this chapter, you should be able to understand: •

the types of emergencies that could affect water utilities

•

the areas that could make a water utility vulnerable

•

the importance of protecting computer systems at a water utility

•

the components of a Vulnerability Assessment


Water Transmission and Distribution: Read chapter 17, System Security and Emergency Response.

OTHER ASSIGNMENTS

107

108


CLASS NOTES 1.

Water supply system threats:

2.

Cyber threats:

3.

Physical threats:

4.

5.

Biological threats:

Chemical threats:

Chapter 17: System Security and Emergency Response

6.

Vulnerability Assessment:

7.

SCADA system security

8.

Early warning system:

9.

Emergency response plan:

109

110


REVIEW QUESTIONS 1.

What types of emergencies could affect a water utility?

2.

Name four major threats to drinking water systems: • • • •

3.

Name five possible vulnerable locations within a water utility: • • • • •

4.

What is included in the computer infrastructure of a water utility?

5.

What type of assessment was required under the Bioterrorism Act of 2002? What is the purpose of this assessment?


111

6.

What actions can be taken by water utility personnel to improve the cyber security of their SCADA networks?

7.

What are early warning systems intended to do?

8.

What is the purpose of an intrusion detection system?

9.

Name five types of intrusion detection sensors: • • • • •

10. How can a water utility’s SCADA system be used for system security?

11. What is the key to emergency response success?

112


STUDY PROBLEM 1.

You have been asked to create an Emergency Response Plan for a small water system that uses a well for its water supply. Using the model Emergency Response Plan described in chapter 17 that was developed for Manitoba as a basis, describe the components that would be included in your plan for this small system.


ADDITIONAL NOTES

113

CHAPTER 18

Public Relations OBJECTIVES After completing study of this chapter, you should be able to understand: •

how public relations enhance a water utility’s image and build goodwill

•

specific personal behaviors that improve or detract from customer relations

•

why informed employees are necessary for a good public relations program

•

how written guidelines can assist personnel in maintaining good relations with customers

•

types of formal public relations programs and how they benefit customer awareness and utility operations


Water Transmission and Distribution: Read chapter 18, Public Relations.

OTHER ASSIGNMENTS

115

116


CLASS NOTES 1.

The role of public relations:

2.

The role of water distribution personnel:

3.

The role of informed employees in public relations:

4.

Formal public relations programs:

Chapter 18: Public Relations

117

REVIEW QUESTIONS 1.

Describe how poor customer relations can adversely affect distribution personnel.

2.

List the three ingredients for maintaining effective public relations with customers. • • •

3.

Identify four behaviors or practices of a meter reader that might help create a favorable public image. • • • •

4.

List six behaviors that utility personnel should avoid when in the presence of the public. • • • • • •

5.

Describe how good safety practices can contribute to an overall public relations program for a water utility.

118


6.

How can water distribution personnel familiarize themselves with safe driving regulations if the utility does not offer a formal training program?

7.

What is the first and foremost rule that water distribution personnel should follow if approached by the media for an opinion or statement?

8.

What are three advantages of having procedural manuals or other written guidelines for personnel in a water utility? • • •

9.

What is the role of a customer service representative?

10. Who is usually the spokesperson for the utility at a formal press conference?

Chapter 18: Public Relations

119

STUDY PROBLEMS 1.

Several public interest groups in the community and two local newspapers are opposing a proposed rate increase that your utility presented to the city council. A significant portion of the increased revenue would be used to employ additional distribution system personnel to allow more frequent routine inspections, maintenance, and repairs. During the past 2 years, the utility has had a severely restricted budget. Its services have been limited to responding to emergencies and making needed repairs. A state environmental group has attacked the utility because of a 5-year plan that involves a major capital development program for a secondary water source, expanded treatment facilities, and a main extension program. Local residents are sympathetic with the plan but see it as potentially increasing the cost of water service. Last week, one of the distribution system operators rear-ended an expensive car at a traffic light, ran over Mrs. Schwartz’s cat, and was seen changing a flat tire on a company truck in front of the Flamingo Tavern. Your utility manager has asked for recommendations on how the organization can improve its public image and confidence. Prepare a brief report stating what you believe to be the underlying problems. Assuming the rate increase becomes effective, outline recommendations that would be appropriate for distribution personnel to follow in order to improve the utility’s public relations posture.

2.

Your repair crew is working in a residential neighborhood. The task requires tearing up a portion of the street, closing one lane of the two-way street, and possibly damaging several lawns. Recommend at least five precautions and actions that will reduce customer inconvenience and foster a good public image in this neighborhood.

120


ADDITIONAL NOTES

(Principles and practices of water supply operations series) American Water Works Association-Water transmission and distribution _ student workbook-American Water Works Association (2010).pdf

Recommend Documents