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Summary of FindingsHistorical Reconstruction of the Water-Distribution System
Serving the Dover Township Area, New Jersey:January 1962–December 1996
Atlanta, Georgia–September 200101-0489
MA
MJ
JA
SO
ND
FJ
MONTH
MO
NT
HLY
PR
OD
UC
TIO
N, I
N M
ILLI
ON
GA
LLO
NS
1962 1
964196
6 1968
1970 1
972197
4 1976
1978 1
980198
2 1984
1986 1
988199
0 1992
1994 1
996
500
450
400
350
300
250
200
150
100
50
0
1995
1988
1971
1962
1996
1996
1995
1988
1971
1962
Front Cover Illustrations:
Upper Images: Maps showing configuration and expansion of the historical water-distribution system networks serving the Dover Township area, New Jersey:
1962, 1971, 1988, 1995, and 1996.
Lower Image: Plot showing three-dimensional representation of monthly water-supply well production for the Dover Township area, New Jersey, January 1962–December 1996.
S
UMMARY
OF
F
INDINGS
H
ISTORICAL
R
ECONSTRUCTION
OF
THE
W
ATER
-D
ISTRIBUTION
S
YSTEM
S
ERVING
THE
D
OVER
T
OWNSHIP
A
REA
, N
EW
J
ERSEY
:
J
ANUARY
1962 – D
ECEMBER
1996
Agency for Toxic Substances and Disease RegistryU.S. Department of Health and Human Services
Atlanta, Georgia
September 2001
ii Summary of Findings: Historical Reconstruction of the Water-Distribution System Serving the DoverTownship Area, New Jersey: January 1962–December 1996
F
OREWORD
The New Jersey Department of Health and SeniorServices (NJDHSS), with support from the Agency forToxic Substances and Disease Registry (ATSDR), isconducting an epidemiologic study of childhood cancersin Dover Township, Ocean County, New Jersey. In 1996,ATSDR and NJDHSS developed a Public HealthResponse Plan in cooperation with the Ocean CountyHealth Department and the Citizens’ Action Committeeon Childhood Cancer Cluster. The plan outlines a seriesof public health activities including assessments ofpotential environmental exposures in the community. In1997, ATSDR and NJDHSS determined that anepidemiologic study was warranted, and that the studywould include assessments of the potential for exposureto specific drinking-water sources.
To assist the epidemiologic efforts, ATSDR developed awork plan to reconstruct historical characteristics of thewater-distribution system serving the Dover Townshiparea by using water-distribution system modelingtechniques. The numerical model chosen for this effort,EPANET 2, is available in the public domain and isdescribed in the scientific literature. To test thereliability of model simulations, water-distributionsystem data specific to the Dover Township area wereneeded to compare with model results. Lacking suchdata, a field-data collection effort was initiated to obtainpressure measurements, storage-tank water levels, andsystem operation schedules (the on-and-off cycling ofwells and pumps) during winter-demand (March 1998)and peak-demand (August 1998) operating conditions.
Using these data, the water-distribution system modelwas calibrated to present-day (1998) conditions. ATSDRreleased a report and a technical paper in June 2000describing the field-data collection activities and modelcalibration results.
Having established the reliability of the model and themodeling approach, the model was used to examine (orreconstruct) historical characteristics of the water-distribution system. For this purpose, monthlysimulations were conducted from January 1962 throughDecember 1996 to es t imate the proport ionatecontribution of water from points of entry (well or wellfields) to various locations throughout the DoverTownship area.
This summary of findings was developed to provide anoverview of the historical reconstruction analysisconducted by ATSDR and NJDHSS. A full descriptionof the analysis is forthcoming in a comprehensivereport. For the historical period, the following topics arepresented in the full report: (1) data sources andrequirements, (2) methods of analysis, (3) simulationapproaches, (4) selected simulation results of thehistorical reconstruction analysis, and (5) the use ofsensitivity analysis to address issues of uncertainty andvariability of historical system operations. Readersinterested in details of the historical reconstructionmethodology, simulation approaches, or results forspecific years and locations for the Dover Township areashould refer to the full report that is available over theIn t e rne t a t t he ATSDR Web s i t e a t URL:
www.atsdr.cdc.gov
.
CONTENTS
Foreword ii
Contents iii
List of Illustrations iv
List of Tables iv
Glossary and Abbreviations v
Disclaimer vi
Background 1
Methods and Approach 3
Specific Data Needs 3
Data Availability, Quality, Methods, and Sources 10
Examples of Simulation Results 16
Sensitivity Analysis 24
References 27
Principal Investigators, Contributors, and Acknowledgements 28
Principal Investigators 28
Contributors 28
Acknowledgements 28
Questions and Answers 29
What is in the ATSDR report? 29
What is a water-distribution system model and which one did ATSDR use? 29
How are ATSDR and NJDHSS using water-distribution system modeling? 29
What type of information did ATSDR and NJDHSS need to conduct the historical reconstruction analysis? 30
What procedures did ATSDR and NJDHSS use to reconstruct historical water-distribution system conditions? 30
What type of information did ATSDR and NJDHSS have regarding historical operations of the water-distribution system serving the Dover Township area? 30
Given the lack of historical system operating information, could the system have operated in a vastly different manner than was used in the model? 31
Has the proportion of water contributed by different well fields to my street remain about the same over the years? 31
What kind of oversight and input from independent experts did ATSDR have for the historical reconstruction approach it used and for review of its findings? 32
Where and how can I obtain a copy of the ATSDR report? 32
Contents iii
CONTENTS—CONTINUED
List of Illustrations
Figures 1–5. Maps showing:
1. Investigation area, Dover Township, Ocean County, New Jersey 2
2. Water-distribution system serving the Dover Township area, New Jersey, 1962 5
3. Water-distribution system serving the Dover Township area, New Jersey, 1971 6
4. Water-distribution system serving the Dover Township area, New Jersey, 1988 7
5. Water-distribution system serving the Dover Township area, New Jersey, 1996 8
Figure 6. Plot showing three-dimensional representation of monthly water-supply well production, Dover Township area, New Jersey, 1962-1996 9
Figures 7–9. Graphs showing annual variation of simulated proportionate contribution of water from wells and well fields to selected locations in the Dover Township area, New Jersey:
7. Minimum-demand months, 1962-1996 18
8. Maximum-demand months, 1962-1996 20
9. Average-demand months, 1962-1996 22
Figure 10. Graph showing results of sensitivity analyses using the manual adjustment process and Genetic Algorithm (GA) optimization for maximum-, minimum- and average-demand months, 1978 25
List of Tables
Table 1. “Master Operating Criteria” used to develop operating schedules for the historical water-distribution system, Dover Township area, New Jersey 10
2. Water-distribution system operating schedule, Dover Township area, New Jersey, May 1962 11
3. Water-distribution system operating schedule, Dover Township area, New Jersey, July 1971 11
4. Water-distribution system operating schedule, Dover Township area, New Jersey, July 1988 12
5. Water-distribution system operating schedule, Dover Township area, New Jersey, June 1996 13
6. Data availability and method of obtaining data for historical reconstruction analysis, Dover Township area, New Jersey 15.
iv Executive Summary: Historical Reconstruction of the Water-Distribution System Serving the DoverTownship Area, New Jersey: January 1962-December 1996
GLOSSARY AND ABBREVIATIONS
Definition of terms and abbreviations used throughout this report are listed below:
Term orAbbreviation Definition
ATSDR Agency for Toxic Substances and Disease Registry
Consumption The use of water by customers of a water utility; is also known as demand. In a water-distribution system, consumption should equal production if there are no losses through leaks or pipe breaks
Direct measurement or A method of obtaining data that is based on measuring or observing observation the parameter of interest.
EPA U.S. Environmental Protection Agency
EPANET 2 A water-distribution system model developed by the EPA
Epidemiologic study A study to determine whether a relation exists between the occurrence and frequency of a disease and a specific factor such as exposure to a toxic compound found in the environment
GA Genetic Algorithm; a method of optimization that attempts to find the most optimal solution by mimicking the mechanics of natural selection and genetics
Historical reconstruction A diagnostic analysis used to examine the historical characteristics of a water-distribution system
Manual adjustment process A modeling approach whereby a balanced flow condition is achieved through the repeated modification and refinement of modeling parameters by the analyst
Master Operating Criteria Guidelines developed for operating a water-distribution system that are based, in part, on hydraulic engineering principles
Maximum-demand month A time during a prescribed year when water usage is greatest; is also known as a peak- or summer-demand period
Minimum-demand month A time during a prescribed year when water usage is least; is alsoknown as a low- or winter-demand period
NJDHSS New Jersey Department of Health and Senior Services
NPL National Priorities List; the EPA’s official list of hazardous waste sites which are to be cleaned up under the Superfund
Point of entry The location where water enters a water-distribution system from asource such as an aquifer, lake, stream, or river. For the DoverTownship area, the points of entry are the wells and well fields
Production The processing of potable water by a water utility and the delivery of the water to locations serviced by the water-distribution system. In a water-distribution system, production should equal consumption if there are no losses through leaks or pipe breaks
Contents v
Proportionate contribution The derivation of water from one or more sources in differingproportions. The sum of the proportionate contribution at anylocation in the water-distribution system should equal 100%
Qualitative description A method of estimating data that is based on inference or issynthesized using surrogate information
Quantitative estimate A method of estimating data by using computational techniques
Sensitivity analysis A method of characterizing or quantifying uncertainty and variability.This involves conducting a series of model simulations, changing specific parameter values, and comparing the effect of the changed parameter(s) with reference to a base condition
Source-trace analysis A method used to identify the source of delivered water using a water-distribution model. A source-trace analysis can be used to track thepercentage of water reaching any point in a distribution system overtime from a specified location or source
System operations The on-and-off cycling of wells and high-service and booster pumps, and the operational extremes of water levels in storage tanks over a 24-hour period
TIGER Topologically integrated, geographic encoding and referencing system; a database developed by the U.S. Department of Commerce thatdescribes in a digital format the locations of roadways, hydrography,landmarks, places, cities, and geographic census boundaries
Water-distribution system A water-conveyance network consisting of hydraulic devices such as wells, reservoirs, storage tanks, and high-service and booster pumps;and a series of pipelines for delivering potable water
DISCLAIMER
Use of trade names and commercial sources is for identification only and does not imply endorsement bythe Agency for Toxic Substances and Disease Registry or the U.S. Department of Health and HumanServices.
For additional information, write to:
Project OfficerExposure-Dose Reconstruction ProjectDivision of Health Assessment and ConsultationAgency for Toxic Substances and Disease Registry1600 Clifton Road, Mail Stop E-32Atlanta, Georgia 30333
vi Summary of Findings: Historical Reconstruction of the Water-Distribution System Serving the DoverTownship Area, New Jersey: January 1962–December 1996
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alm2
SUMMARY OF FINDINGS
HISTORICAL RECONSTRUCTION OF THE WATER-DISTRIBUTION SYSTEM SERVING THE
DOVER TOWNSHIP AREA, NEW JERSEY:JANUARY 1962–DECEMBER 1996
BACKGROUND
Contamination of groundwater resourcesin Dover Township, Ocean County, NewJersey (Figure 1), including the contaminationof water-supply wells, was identified in the1960s (Toms River Chemical Corporation1966) and subsequently documented in the1970s (ATSDR 2001a,b,c,d). Based on publichealth assessments conducted for the DoverTownship area, the Agency for Tox icSubstances and Disease Registry (ATSDR)and the New Jersey Department of Health andSenior Services (NJDHSS) have determinedthat completed human exposure pathways togroundwater contaminants have occurredthrough private and community water supplies(ATSDR 2001a,b,c,d). As a result, NJDHSSand ATSDR are conducting an epidemiologicstudy of childhood leukemia and nervoussystem cancers that occurred in DoverTownship. The epidemiologic study isexploring a variety of possible risk factors,including environmental exposures. To assistNJDHSS with the environmental exposureassessment component of the epidemiologicstudy, ATSDR developed a water-distribution
mode l us ing the EPANET 2 so f twar(Rossman 2000). Results obtained from tmodel will be used to assess exposure tdr ink ing water sources that are beininvestigated as potential risk factors in thepidemiologic investigation.
Because of the lack of appropriathistorical data, the EPANET 2 model wacalibrated to the present-day (1998) watedistribution system characteristics using datacollected during March and August 1998. Threliabi l i ty of the cal ibrated model wasdemonstrated by successfully conductingwater-quality simulation of the transport of naturally occurring conservative element—barium—and comparing results with datcollected at 21 schools and 6 points of entrythe water-distribution system during Marcand April 1996. Results of the field-datcollection activities, model calibration, anreliability testing were described previousl(Maslia et al. 2000a,b). Following calibration,the model was used to simulate historiccharacteristics of the water-distribution systeserving the Dover Township area from 196through 1996.
Background 1
2 Summary of Findings: Historical Reconstruction of the Water-Distribution System Serving the Dover Township Area, New Jersey: January 1962–December 1996
0 5 10 15 MILES
0 1 2 3 MILES
N
Water body
Dover Township
Ciba–Geigy NPL Site
Reich Farm NPL Site
Hydrography
Major road
Street0 20 40 MILES
NEW JERSEY Ocean County
BA
RN
EG
AT
BA
Y
Silver Bay
JACKSONTOWNSHIP
LAKEWOODTOWNSHIP BRICK
TOWNSHIP
BERKELEYTOWNSHIP
South T
oms
River B
orough
Island HeightsBorough
Sea
sid
e H
eig
hts
Bo
rou
gh
EXPLANATION
Green
Branch
Davenpor
t Branch
Jakes
Branc
h
Toms River
WrangleBrook
To
ms
River
Tom
s
River
MANCHESTERTOWNSHIP
OceanCounty
DoverTownship
State Highway
70
Church Road
State Highway 37
Avenue
Hoo
per
Bay B
ay Avenue
FischerB
oulevard
Avenue
Washington St
State
Highway 37
Route
9
Gar
den
Stat
eP
arkw
ay
Figure 1. Investigation area, Dover Township, Ocean County, New Jersey.
Roads, hydrography, and boundaries based on 1995 TIGER/Line data
hel
f
seed-
eisngn.
lmdenfd
,e-
hek(5)ticn
ofndin
This document is a summary of a detailedreport that describes the historical recon-struction analysis. This summary and the fullreport are viewed as companion documents toMaslia et al. (2000a) which describes theanalysis of the 1998 water-distribution systemserving the Dover Township area. The fullreport focuses on the historical reconstructionanalysis of the water-distribution systemincluding: (1) data sources and requirements,(2) methods of analysis, (3) simulationstrategies, (4) selected simulation results, and(5) the use of sensitivity analysis to addressissues of uncertainty and variabil i ty ofhistorical system operations.
METHODS AND APPROACH
Given the pauc i t y o f h is to r i ca lcontaminant-specific concentration data duringmost o f the per i od re levant to theepidemiologic study, ATSDR and NJDHSSdec ided that model ing e ffo r ts shou ldconcentrate on estimating the percentage ofwater that a study subject might have receivedfrom each point of entry (well or well fields) tothe water-distribution system (Figure 2). Thisapproach uses the concept of “proportionatecontribution” described in Maslia et al.(2000a, p. 4) wherein at any given point in thedistribution system, water may be derived fromone or more sources in differing proportions.
Databases were developed from diversesources of information and were used todescribe the historical distribution-systemnetworks specific to the Dover Township area.These data were applied to EPANET 2 andsimulations were conducted for each month of
the historical period—January 1962 througDecember 1996 (420 simulations or “modruns”). After completing the 420 monthlyanalyses, source-trace analysis simulationswere conducted to determine the percentage owater contributed by each well or well fieldoperating during each month. Results of theanalyses—the percentage of water derivfrom the different sources that historically supplied the water-distribution system—werprovided to health scientists for their analysin assessing the environmental factors beiconsidered by the epidemiologic investigatio
SPECIFIC DATA NEEDS
A simulation approach to the historicareconstruction of the water-distribution systein the Dover Township area requ i reknowledge of the functional as well as thphysical characteristics of the distributiosystem. Accordingly, six specific types oinformation were required: (1) pipeline annetwork configurations for the distributionsystem; (2) potable water-production dataincluding information on the locat ioncapaci ty, and t ime of operat ion of thgroundwater production wells; (3) consumption or demand data at locations throughout td is t r ibu t ion sys tem; (4) s torage- tancapacities, elevations, and water-level data; high-service and booster pump characteriscurves; and (6) system-operations informatiosuch as the on-and-off cycling schedule wells and high-service and booster pumps, athe operational extremes of water levels storage tanks.
Methods and Approach 3
tedsd,f-nd
ofhee-hege-
d,oreye),P.,bys
t
Examples of the histor ical networkconfigurations for 1962, 1971, 1988, and 1996are shown in Figures 2 through 5, respectively.(Yearly historical network configurations mapsfor the period 1962 through 1996 are presentedin the full report.) Figures 2 through 5 showthe complexity of the system increasedsignif icantly over the t ime span of thehistorical period. For example, the 1962 water-distribution system served nearly 4,300customers from a population of about 17,200persons (Board of Public Utilities, State ofNew Jersey 1962) and was characterized formodeling by (Figure 2):
• approximately 2,400 pipe segmentsranging in diameter from 2 to 12 inchesand comprising a total service length of 77miles;
• 3 groundwater extraction wells with arated capacity of 1,900 gallons per minute;
• 1 elevated storage tank and standpipe witha combined rated storage capacity of 0.45million gallons; and
• production of about 1.3 million gallonsper day during the peak-production monthof May.
By contrast, in 1996—the last year of thehistorical reconstruction period—the water-distribution system served nearly 44,000customers from a population of about 89,300persons (Board of Public Utilities, State ofNew Jersey 1996) and was characterized formodeling by (Figure 5):
• more than 16,000 pipe segments rangingin diameter from 2 to 16 inches andcomprising a total service length of 482miles;
• 20 groundwater extraction wells with arated capacity of 16,550 gallons perminute;
• 12 high-service or booster pumps;
• 3 elevated and 6 ground-level storagetanks with a combined rated capacity of7.35 million gallons; and
• production of about 13.9 million gallonsper day during the peak-production monthof June.
Analysis of production data indicates thathe historical distribution systems could bcharacterized by three typical demand perioeach year: (1) a low- or winter-demand periogeneral ly represented by the month oFebruary—designated as the minimumdemand month; (2) a peak- or summer-demaperiod, represented by one of the monthsMay, June, July, or August—designated as tmaximum-demand month; and (3) an averagdemand period, generally represented by tmonth of October—designated as the averademand month.
Water-production data were gathereaggregated, and analyzed for each well fevery month of the historical period. Thesdata were obtained from the water utilit(Flegal 1997), Board of Public Utilities, Statof New Jersey, Annual Reports (1962–1996and NJDHSS data searches (Michael McLinden, written communication, August 281997). The production data were measured using in-line flow meters at water-supply well(George J. Flegal, Manager, United WaterToms River, Inc., oral communication, Augus28, 2001).
4 Summary of Findings: Historical Reconstruction of the Water-Distribution System Serving the Dover Township Area, New Jersey: January 1962–December 1996
Specific Data Needs 5
South T
oms
River B
orough
BA
RN
EG
AT
B
AY
Silver Bay
Toms River
MANCHESTERTOWNSHIP
BERKELEY TOWNSHIP
LAKEWOOD TOWNSHIP
BRICK TOWNSHIP
Figure 2. Water-distribution system serving the Dover Township area, New Jersey, 1962.
Wells 13,14
C
A
D
E
B
Well15
Horner Streettank and standpipe
N
Water body
Dover Township
Ciba–Geigy NPL Site
Reich Farm NPL Site
Hydrography
Major road
Water pipeline Municipal well
Storage tank
EXPLANATION
Notes: (1) Water pipelines range in diameter from 2 inches to 12 inches(2) Roads, hydrography, and boundaries based on 1995 TIGER/Line data
D Pipeline location and letter. Percent contribution is reported in text
0 1 2 3 MILES
6 Summary of Findings: Historical Reconstruction of the Water-Distribution System Serving the Dover Township Area, New Jersey: January 1962–December 1996
South T
oms
River B
orough
BA
RN
EG
AT
B
AY
Silver Bay
Toms River
MANCHESTERTOWNSHIP
BERKELEY TOWNSHIP
LAKEWOOD TOWNSHIP
BRICK TOWNSHIP
Well20
Well15
Wells 14,16,18,19,21
Well 17
Wells 22,23,26,27
Indian Hillelevated
Parkwayground level
Silver Bay Well
AnchorageWell
Holly Plantground level
South Toms Riverelevated
C
A
D
E
B
N
EXPLANATION
Notes: (1) Water pipelines range in diameter from 2 inches to 16 inches(2) Roads, hydrography, and boundaries based on 1995 TIGER/Line data
Figure 3. Water-distribution system serving the Dover Township area, New Jersey, 1971.
Water body
Dover Township
Ciba–Geigy NPL Site
Reich Farm NPL Site
Hydrography
Major road
Water pipeline Municipal well
Storage tank
D Pipeline location and letter. Percent contribution is reported in text
0 1 2 3 MILES
Specific Data Needs 7
South T
oms
River B
orough
BA
RN
EG
AT
B
AY
Silver Bay
Toms River
MANCHESTERTOWNSHIP
BERKELEY TOWNSHIP
LAKEWOOD TOWNSHIP
BRICK TOWNSHIP
Well 20
Well31
Well15
Wells 33,34,35
Wells21,30
Wells 32,38
Wells 22,23,24,26,28,29
Indian Hillelevated
Parkwayground level
Holiday Cityground level
Route 37ground level
Holly Plantgroundlevel
South Toms Riverelevated
Windsorground level
C
A
D
E
B
N
EXPLANATION
Notes: (1) Water pipelines range in diameter from 2 inches to 16 inches(2) Roads, hydrography, and boundaries based on 1995 TIGER/Line data
Figure 4. Water-distribution system serving the Dover Township area, New Jersey, 1988.
Water body
Dover Township
Ciba–Geigy NPL Site
Reich Farm NPL Site
Hydrography
Major road
Water pipeline Municipal well
Storage tank
D Pipeline location and letter. Percent contribution is reported in text
0 1 2 3 MILES
8 Summary of Findings: Historical Reconstruction of the Water-Distribution System Serving the Dover Township Area, New Jersey: January 1962–December 1996
South T
oms
River B
orough
BA
RN
EG
AT
B
AY
Silver Bay
Toms River
MANCHESTERTOWNSHIP
BERKELEY TOWNSHIP
LAKEWOOD TOWNSHIP
BRICK TOWNSHIP
Well 20
Well 31
Well15
Wells 33,34,35
Wells21,30,37
Wells 32,38
Wells 22,24,26, 28,29,39,41,42
Indian Hillelevated
Parkwayground level
Holiday Cityground level
Well40
Route 37ground level
Holly Plantgroundlevel
South Toms Riverelevated
Windsorground level
North Doverelevated
C
A
D
E
B
N
EXPLANATION
Notes: (1) Water pipelines range in diameter from 2 inches to 16 inches(2) Roads, hydrography, and boundaries based on 1995 TIGER/Line data
Figure 5. Water-distribution system serving the Dover Township area, New Jersey, 1996.
Water body
Dover Township
Ciba–Geigy NPL Site
Reich Farm NPL Site
Hydrography
Major road
Water pipeline Municipal well
Storage tank
D Pipeline location and letter. Percent contribution is reported in text
0 1 2 3 MILES
i-of,
rere-
ntoi-
ead
Month ly p roduc t i on da ta can berepresented graphically as shown in a three-dimensional plot (Figure 6). Referring to thisplot, the x-axis is the year (1962–1996), the y-axis is the month (January–December), and thez-axis is the total monthly production inmillion gallons. Maximum production isshown to occur in the months of May, June,July, or August. In addition, considerableproduction increases occurred in 1971, 1988,and 1995. These years are characterized on theplot by sharp peaks.
As noted previously, to simulate the distrbution of water for each of the 420 months the historical period, network configurationdemand, and operational information werequired. Before 1978, operational data weunavailable requiring development of systemoperation parameters—designated as “MasterOperating Criteria.” These are based ohydraulic engineering principles necessary successfully operate distribution systems simlar to the one serving the Dover Township ar(Table 1). From 1978 forward, for selecte
Specific Data Needs 9
MAM
JJA
SO
ND
FJ
MONTH
MO
NT
HLY
PR
OD
UC
TIO
N, I
N M
ILLI
ON
GA
LLO
NS
1962 1
964196
6 1968
1970 1
972197
4 1976
1978 1
980198
2 1984
1986 1
988199
0 1992
1994 1
996
500
450
400
350
300
250
200
150
100
50
0
1988
1971
1962
Figure 6. Three-dimensional representation of monthly water-supply well production, Dover Township area, New Jersey, 1962–96.
y x
z
1996
1995
ly
nreatepsm5);e 5
drnt
tbed of
tainct,
calornto
e
years, operators of the water utility providedinformation on the generalized operating prac-tices for a typical “peak-demand” (summer)and “non-peak demand” (fall) day. Theseguidelines were used in conjunction with the“Master Operating Criteria” to simulate a typi-cal 24-hour daily operation of the water-distri-bution system for each month of the historicalperiod.
Examples of historical water-distributionsystem operating schedules for the maximum-demand months of May 1962, July 1971, July1988, and June 1996 are shown in Tables 2through 5, respectively. These tables indicatethe hour-by-hour operation of wells and high-service and booster pumps during a typical dayof the maximum-demand month for the givenyear. Note that in 1962 (Table 2), high-serviceand booster pumps were not part of thedistribution system and, therefore, only
groundwater wells were operated to suppdemand by discharging water directly into thedistribution system (wells 13–15, Figure 2). I1968, high-service and booster pumps weadded to the distribution system. From thyear forward, some wells supplied storagtanks, then high-service and booster pumwere operated to meet distribution-systedemands (wells 21–30, 40, and 42, Figure other wells still discharged directly into thdistribution system (refer to Tables 2 throughfor details).
DATA AVAILABILITY, QUALITY, METHODS, AND SOURCES
In this type of study, the ideal or desirecondition is to obtain all data required fomodel simulations through direct measuremeor observation. In reality, however, necessarydata are not routinely available by direcmeasurement or observation and must synthes ized us ing general ly accepteengineering analyses and methods. Issuesdata sources and the methods used to obdata that cannot be directly measured refleultimately, on the credibility of simulationresults. To address these issues for historireconstruction analysis, the methods fobtaining the necessary data were grouped ithree categories (Table 6):
• Direct measurement or observation—Data included in this category wereobtained by direct measurement orobservation of historical data and areverifiable by independent means. Of thethree data categories, these data were thmost preferred in terms of reliability andleast affected by issues of uncertainty.
Table 1. “Master Operating Criteria” used to develop operating schedules for the historical water-distribution system, Dover Township area, New Jersey
Parameter CriteriaPressure1
1Generally, for residential demand, minimum recommended pres-sure is about 20 pounds per square inch. However, for some locations in the Dover Township area (mostly in areas near the end of distribution lines) lower pressures were simulated.
Minimum of 15 pounds per square inch, maximum of 110 pounds per square inch at pipeline locations, including network end points
Water level Minimum of 3 feet above bottom elevation of tank; maximum equal to elevation of top of tank; ending water level should equal the starting water level
Hydraulic device on-line date
June 1 of year installed to meet maximum-demand conditions
On-and-off cycling: Manual operation
Wells and high-service and booster pumps cannot be cycled on-and-off from 2200 to 0600 hours
On-and-off cycling: Automatic operation
Wells and high-service and booster pumps can be cycled on-and-off at any hour
Operating hours Wells should be operated continuously for the total number of production hours, based on production data2
2See full report for historical monthly production data.
10 Summary of Findings: Historical Reconstruction of the Water-Distribution System Serving the Dover Township Area, New Jersey: January 1962–December 1996
Data Availability, Quality, Methods, and Sources 11
Tab
le 2
.W
ater
-dis
trib
utio
n sy
stem
ope
ratin
g sc
hedu
le, D
over
Tow
nshi
p ar
ea, N
ew J
erse
y,
Wat
er-d
istr
ibut
ion
syst
em o
pera
ting
sche
dule
, Dov
er T
owns
hip
area
, New
Jer
sey,
May
196
2[M
ay is
max
imum
-dem
and
mon
th fo
r 19
62; h
our
of d
ay in
col
or m
eans
wel
l ope
ratin
g;
G
roun
dwat
er w
ell]
Wel
l ID
1
1 Wel
ls d
isch
arge
dire
ctly
into
the
dist
ribut
ion
syst
em.
Ho
ur
of
the
Day
2
2 Hou
r of
the
day:
0 is
mid
nigh
t; 12
is n
oon,
res
pect
ivel
y.
01
23
45
67
89
1011
1213
1415
1617
1819
2021
2223
Gro
un
dw
ater
Wel
l
Hol
ly (
13)
Hol
ly (
14)
Bro
oksi
de (
15)
Tab
le 3
. Ju
ly 1
971
[Jul
y is
max
imum
-dem
and
mon
th fo
r 19
71; h
our
of d
ay in
col
or m
eans
wel
l or
pum
p op
erat
ing;
Gro
undw
ater
wel
l;
H
igh-
Ser
vice
or
Boo
ster
pum
p]
Wel
l ID
1
1 Wel
ls d
isch
arge
dire
ctly
into
the
dist
ribut
ion
syst
em.
Ho
ur
of
the
Day
2
2 Hou
r of
the
day:
0 is
mid
nigh
t; 12
is n
oon,
res
pect
ivel
y.
01
23
45
67
89
1011
1213
1415
1617
1819
2021
2223
Gro
un
dw
ater
Wel
l
Bro
oksi
de (
15)
Sou
th T o
ms
Riv
er (
17)
Indi
an H
ead
(20)
Anc
hora
ge3
3 Anc
hora
ge a
nd S
ilver
Bay
do
not h
ave
wel
l num
bers
des
igna
ted
by w
ater
util
ity.
Silv
er B
ay3
Hig
h-S
ervi
ce o
r B
oo
ster
Pu
mp
Pu
mp
IDH
olly
pum
p 14
4 Hol
ly p
ump
1, H
olly
pum
p 2,
and
Hol
ly p
ump
3 su
pplie
d by
Hol
ly g
roun
d-le
vel s
tora
ge ta
nks
and
Hol
ly w
ells
14,
16,
18,
19,
and
21.
Hol
ly p
ump
24 4
Hol
ly p
ump
3
Par
kway
pum
p 15 5
5 Par
kway
pum
p 1
and
Par
kway
pum
p 2
supp
lied
by P
arkw
ay g
roun
d-le
vel s
tora
ge ta
nk a
nd P
arkw
ay w
ells
22,
23,
26,
and
27.
Par
kway
pum
p 2
12 Summary of Findings: Historical Reconstruction of the Water-Distribution System Serving the Dover Township Area, New Jersey: January 1962–December 1996
, Ju
ly 1
988
[Jul
y is
max
imum
-dem
and
mon
th fo
r 19
88; h
our
of d
ay in
col
or m
eans
wel
l or
pum
p op
erat
ing;
Gro
undw
ater
wel
l;
H
igh-
Ser
vice
or
Boo
ster
pum
p]
Wel
l ID
1
1 Wel
ls d
isch
arge
dire
ctly
into
the
dist
ribut
ion
syst
em.
Ho
ur
of
the
Day
2
2 Hou
r of
the
day:
0 is
mid
nigh
t; 12
is n
oon,
res
pect
ivel
y.
01
23
45
67
89
1011
1213
1415
1617
1819
2021
2223
Gro
un
dw
ater
Wel
lB
rook
side
(15
)
Indi
an H
ead
(20)
Rou
te 7
0 (3
1)
Sou
th T
oms
Riv
er (
32)
Ber
kele
y (3
3)
Ber
kele
y (3
4)
Ber
kele
y (3
5)
Sou
th T
oms
Riv
er (
38)
Hig
h-S
ervi
ce o
r B
oo
ster
Pu
mp
Pu
mp
ID
Hol
ly p
ump
13
3 Hol
ly p
ump
1, H
olly
pum
p 2,
and
Hol
ly p
ump
3 su
pplie
d by
Hol
ly g
roun
d-le
vel s
tora
ge ta
nks
and
Hol
ly w
ells
21
and
30.
Hol
ly p
ump
23
Hol
ly p
ump
33
Par
kway
pum
p 14
4 Par
kway
pum
p 1
and
Par
kway
pum
p 2
supp
lied
by P
arkw
ay g
roun
d-le
vel s
tora
ge ta
nk a
nd P
arkw
ay w
ells
22,
23,
24,
26,
28,
and
29.
Par
kway
pum
p 24
Hol
iday
City
Pum
p5
5 Pum
p op
erat
ed fr
om 0
630
to 1
130
hour
s an
d 16
30 to
203
0 ho
urs.
St.
Cat
herin
e’s
pum
p 6, 7
6 Pum
p op
erat
ed fr
om 0
930
to 1
445
hour
s.7A
lso
know
n as
Rou
te 3
7.
Sou
th T
oms
Riv
er p
ump
1
Sou
th T
oms
Riv
er p
ump
2
Win
dsor
pum
p 18 8
8W
inds
or p
ump
1 and
Win
dsor
pum
p 2 su
pplie
d by
Win
dsor
gro
und-
leve
l tan
k.
Win
dsor
pum
p 2
Tab
le 4
.W
ater
-dis
trib
utio
n sy
stem
ope
ratin
g sc
hedu
le, D
over
Tow
nshi
p ar
ea, N
ew J
erse
y,
Data Availability, Quality, Methods, and Sources 13
June
199
6[J
une
is m
axim
um-d
eman
d m
onth
for
1996
; hou
r of
day
in c
olor
mea
ns w
ell o
r pu
mp
oper
atin
g;
G
roun
dwat
er w
ell;
Hig
h-S
ervi
ce o
r B
oost
er p
ump]
Wel
l ID
1
1 Wel
ls d
isch
arge
dire
ctly
into
the
dist
ribut
ion
syst
em.
Ho
ur
of
the
day
2
2 Hou
r of
the
day:
0 is
mid
nigh
t; 12
is n
oon,
res
pect
ivel
y.
01
23
45
67
89
1011
1213
1415
1617
1819
2021
2223
Gro
un
dw
ater
Wel
lB
rook
side
(15
)
Rou
te 7
0 (3
1)
Sout
h To
ms
Riv
er (
32)
Ber
kele
y (3
3)
Ber
kele
y (3
4)
Ber
kele
y (3
5)
Sout
h To
ms
Riv
er (
38)
Pu
mp
IDH
igh
-Ser
vice
or
Bo
ost
er P
um
p
Hol
ly p
ump
13
3 Hol
ly p
ump
1, H
olly
pum
p 2,
and
Hol
ly p
ump
3 su
pplie
d by
Hol
ly g
roun
d-le
vel s
tora
ge ta
nks
and
Hol
ly w
ell 3
0.
Hol
ly p
ump
23 3H
olly
pum
p 3
Park
way
pum
p 14
4 Par
kway
pum
p 1
and
Par
kway
pum
p 2
supp
lied
by P
arkw
ay g
roun
d-le
vel s
tora
ge ta
nk a
nd P
arkw
ay w
ells
22,
24,
26,
28,
29,
and
42.
Park
way
pum
p 24
Hol
iday
City
pum
p
St. C
athe
rine’
s pu
mp5
5 Als
o kn
ow a
s R
oute
37.
Sout
h To
ms
Riv
er p
ump
1
Sout
h To
ms
Riv
er p
ump
2
Win
dsor
pum
p 16 6 6
6W
inds
or p
ump
1, W
inds
or p
ump
2, a
nd W
inds
or p
ump
3 su
pplie
d by
Win
dsor
gro
und-
leve
l sto
rage
tank
and
Win
dsor
wel
l 40.
Win
dsor
pum
p 2
Win
dsor
pum
p 3
Tab
le 5
.W
ater
-dis
trib
utio
n sy
stem
ope
ratin
g sc
hedu
le, D
over
Tow
nshi
p ar
ea, N
ew J
erse
y,
aledofgst
efee
ofdo
nsde)d-e
alr
h,
ps).ekesesey
edtol
• Quantitative estimates—Data included inthis category were estimated or quantifiedusing computational methods.
• Qualitative description—Data included inthis category were based on inference orwere syn thes ized us ing sur rogateinformation. Of the three data categories,data derived by qualitative descriptionwere the least preferred in terms ofreliability and the most affected by issuesof uncertainty.
Of the six specific types of informationrequired for the historical reconstruction anal-ysis, the network pipeline data, groundwaterwell-location data, groundwater well-produc-tion data, and storage-tank data were obtainedby direct measurement or observation (Table6). These data were available throughout theentire historical period and they could beassessed for quality and verified by indepen-dent means such as state reports or field obser-vations. For example, groundwater well-production data were available for every wellfor every month of the historical period andthese data were measured by the water utilityusing in-line flow-metering devices at ground-water wells (George J. Flegal, Manager,United Water Toms River, Inc., oral communi-cation, August 28, 2001).
Data for historical consumption (ordemand) consisted of two components—monthly volumes (quantity) and spatialdistribution (location). The monthly volumeswere obtained by using a quant i tat iveestimation method. Data were available frommetered billing records for October 1997through April 1998 and verified through thecalibration process described in Maslia et al.
(2000a,b); the magnitude of monthly historicproduction was known based on measurflow data. Using these data, estimates historical demand were quantified by imposinthe requirement that total consumption muequal total production.
Direct measurement or quanti tat ivest imates of the spatial distr ibut ion ohistorical demand were not available for thDover Township area. Therefore, qualitativdescription methods were used to estimatehistorical data values. In doing so, estimatesthe spatial distribution of historical deman(demand pat terns) were based on twassumptions: (1) historical demand patterwere similar to the present-day demanpatterns which are known from availablmetered billing records (Table 6); and (2demand patterns could be inferred from lanuse classification using historical land-usclassification as a surrogate indicator. Toassess the validity of this approach, historicland-use classification or zoning maps foDover Township were used in conjunction witdistribution-system network maps for 19621967, 1978, 1990, and 1996 (network malike the ones shown in Figures 2 through 5Using information obtained from the land-usclassification and distribution-system networmaps, geospatial and comparative analyswere conducted. Results of these analysindicated that the distribution of land-usclassification in Dover Township was relativelstatic and changed little during the historicalperiod. These analyses substantially validatthe qualitative description method used estimate the spatial distribution of historicademand.
14 Summary of Findings: Historical Reconstruction of the Water-Distribution System Serving the Dover Township Area, New Jersey: January 1962–December 1996
Data Availability, Quality, Methods, and Sources 15
Tab
le 6
. D
ata
avai
labi
lity
and
met
hod
of o
btai
ning
dat
a fo
r hi
stor
ical
rec
onst
ruct
ion
anal
ysis
, Dov
er T
owns
hip
area
, Ne
w J
erse
y
Dat
a Ty
pe
Tim
e F
ram
e o
f A
vaila
bili
tyS
ou
rce
Met
ho
d o
f O
bta
inin
g D
ata
1
1 Dire
ct m
easu
rem
ent o
r ob
serv
atio
n—m
easu
red
or o
bser
ved
data
ava
ilabl
e fo
r so
me
or th
roug
hout
his
toric
al p
erio
d; d
ata
verifi
able
by
inde
pend
ent m
eans
; Q
uant
itativ
e es
timat
e—di
rect
mea
sure
men
t or
obse
rvat
ion
of h
isto
rical
dat
a no
t ava
ilabl
e fo
r so
me
or m
ost o
f his
toric
al p
erio
d; d
ata
estim
ated
by
com
puta
tiona
l met
hods
; Q
ualit
ativ
e de
scrip
tion—
dire
ct m
easu
rem
ent o
r ob
serv
atio
n of
his
toric
al d
ata
not a
vaila
ble
for
mos
t or
all o
f hi
stor
ical
per
iod
; dat
a ba
sed
on in
fere
nce
or s
ynth
esiz
ed
No
tes
Dir
ect
Mea
sure
men
t o
r O
bse
rvat
ion
Qu
anti
tati
veE
stim
ate
Qu
alit
ativ
e D
escr
ipti
on
Pipe
line
loca
tion
and
geom
etry
1962
–199
6W
ater
util
ity d
atab
ase
2
2 Fle
gal (
1997
).
xIn
-ser
vice
dat
e as
sign
ed to
be
Janu
ary
1 of
in
-ser
vice
yea
r
Gro
undw
ater
wel
l lo
catio
n19
62–1
996
Wat
er u
tility
dat
abas
eB
oard
of P
ublic
Util
ities
rep
orts3 ,
ATS
DR
and
NJD
HS
S fi
eld
verifi
catio
n
3 B
oard
of P
ublic
Util
ities
, Sta
te o
f New
Jer
sey,
Ann
ual R
epor
ts (
1962
–199
6).
xIn
-ser
vice
dat
e as
sign
ed to
be
June
1 o
f in
-ser
vice
yea
r
Gro
undw
ater
wel
l pr
oduc
tion
1962
–199
6W
ater
util
ity d
atab
ase
2 ,2 ,
Boa
rd o
f Pub
lic U
tiliti
es A
nnua
l Rep
orts3 ,
NJD
HS
S d
ata
sear
ch4
4 Mic
hael
P. M
cLin
den,
writ
ten
com
mun
icat
ion,
Aug
ust 2
8, 1
997.
xW
ater
util
ity d
ata,
196
2–19
96; N
JDH
SS
da
ta, 1
962–
1979
; dat
a fr
om in
-line
flow
met
ers5 ,
hou
rly v
alue
s av
aila
ble
for
1996
;pr
ior
to 1
996,
mon
thly
val
ues
avai
labl
e;
aver
age
daily
ope
ratio
n es
timat
ed fr
om
mon
thly
dat
a an
d w
ell c
apac
ity
5 Geo
rge
J. F
lega
l, M
anag
er, U
nite
d W
ater
Tom
s R
iver
, Inc
., or
al c
omm
unic
atio
n, A
ugus
t 28,
200
1.
Stor
age
tank
ge
omet
ry, c
apac
ity,
and
loca
tion
1962
–199
6W
ater
util
ity d
atab
ase
2 ,
Boa
rd o
f Pub
lic U
tiliti
es A
nnua
l Rep
orts3 ,
ATS
DR
and
NJD
HS
S fi
eld
verifi
catio
n
xIn
-ser
vice
dat
e as
sign
ed to
be
June
1 o
f in
-ser
vice
yea
r
Est
imat
ion
of
cons
umpt
ion
(dem
and)
(dem
and)
Oct
ober
199
7–A
pril
1998
Wat
er u
tility
bill
ing
reco
rds,
AT
SD
R c
alib
rate
d m
odel6
6 Mas
lia et
al.
(200
0a, b
).
xP
rior
to O
ctob
er 1
997,
dat
a no
t ava
ilabl
e to
in
vest
igat
ors;
qua
ntita
tive
estim
ate
base
d on
ass
umpt
ion
that
dem
and
mus
t equ
al
prod
uctio
n
Spat
ial d
istr
ibut
ion
of c
onsu
mpt
ion
Oct
ober
199
7–A
pril
1998
Wat
er u
tility
bill
ing
reco
rds,
ATS
DR
cal
ibra
ted
mod
el6x
Prio
r to
Oct
ober
199
7, d
ata
not a
vaila
ble
to
inve
stig
ator
s; e
stim
ates
bas
ed o
n qu
alita
tive
asse
ssm
ent o
f lan
d-us
e an
d ge
ospa
tial a
naly
sis
Pum
p-ch
arac
teris
tic
curv
es19
98W
ater
util
ity d
ata2 ,
ATS
DR
cal
ibra
ted
mod
el6x
Syst
em o
pera
tions
,
196
2–19
77N
one
Non
e
“Mas
ter
Ope
ratin
g hy
drau
lic e
ngin
eerin
g pr
inci
ples
, w
ater
util
ity o
pera
ting
prac
tices
x
Syst
em o
pera
tions
,
197
8–19
87Ty
pica
l pea
k da
y (s
umm
er)
and
non-
peak
day
(fa
ll)
for
sele
cted
yea
rs
Wat
er u
tility
ope
ratio
nal n
otes7 ,
“M
aste
r O
pera
ting
Crit
eria
,”
Crit
eria
,”
Crit
eria
,”
hydr
aulic
eng
inee
ring
prin
cipl
es
hydr
aulic
eng
inee
ring
prin
cipl
es,
7 Ric
hard
Otte
ns, J
r., P
rodu
ctio
n M
anag
er, U
nite
d W
ater
Tom
s R
iver
, Inc
., w
ritte
n co
mm
unic
atio
n, 1
998.
xx
Hig
h-se
rvic
e an
d bo
oste
r pu
mp
disc
harg
e es
timat
ed fr
om w
ater
util
ity n
otes
Dai
ly h
ours
of o
pera
tion
for
wel
ls fr
ompr
oduc
tion
data
Syst
em o
pera
tions
,
198
8–19
96W
ater
util
ity o
pera
tiona
l not
es7 ,“M
aste
r O
pera
ting
obse
rved
wat
er-u
tility
op
erat
ing
prac
tices6
xx
xH
igh-
serv
ice
and
boos
ter
pum
p di
scha
rge
estim
ated
from
wat
er u
tility
not
es; h
ourly
op
erat
ions
dat
a fo
r 19
96
usin
g su
rrog
ate
info
rmat
ion.
Typi
cal p
eak
day
(sum
mer
)an
d no
n-pe
ak d
ay (
fall)
fo
r se
lect
ed y
ears
; all
of 1
996;
and
Mar
ch a
nd
Aug
ust 1
998
t
ro-n
ern-n
ntedn,ip-tangheer
.,
esg
dtoh
dad
s
The high-service and booster pump-characterist ic data were derived usinginformation obtained from the water utility(Flegal 1997). This information consisted ofhead values versus flow values which wererefined during the model calibration process(Maslia et al. 2000a,b).
The historical system-operation data wereobtained using each of the three methods ofobtaining data descr ibed previously—depending on the time frame (Table 6). For theear l y h is to r ica l pe r i od (1962-1977) ,investigators relied on hydraulic engineeringprinciples and the “Master Operating Criteria”(Table 1). Because data describing specificoperational practices were not available,operating schedules developed for these earlyhistorical networks (for example, Table 2 andTable 3) were based on qualitative descriptionsof system operations. To maintain a balancedflow condition however, water-distributionsystems of similar configuration and facilitiesas the historical Dover Township area system,generally operate using on-and-off cyclingschedules of limited variability. That is, wellsand high-service and booster pumps must becycled on-and-off within a limited or narrowoperating range. Simulations conducted on thewater-distribution system serving the DoverTownsh ip area conf i rmed the l im i tedvariability of the on-and-off cycling operatingschedule.
For the 1977–1987 period, system-opera-tion data were developed from quantitativeestimates and qualitative descriptions of theoperating schedules (Table 6). These data werederived using hydraulic engineering principles,
the “Master Operating Criteria,” and frominformation provided by the water utility thadescribed the general operations of the water-distribution system for a typical “peak” day(summer) and a “non-peak” (fall) day. Fosome of the years, the water utility also prvided estimates of discharge to the distributiosystem from the high-service and boostpumps (Richard Ottens, Jr., Production Maager, United Water Toms River, Inc., writtecommunication, 1998).
System-operation data for the most recehistorical systems (1988–1996) were obtainfrom direct measurement or observatioquantitative estimates, and qualitative descrtions of operating schedules (Table 6). Dasources used to develop these operatischedules (for example, Table 5) included tgeneralized operating notes from the watut i l i ty (Richard Ottens, Jr., ProductionManager, United Water Toms River, Incwri t ten communication, 1998), hour lyoperations data for 1996 (Flegal 1997), nottaken by ATSDR and NJDHSS staff durinfield-data collection activities in March andApril 1998 (Maslia et al. 2000a), and theobservation that the distribution system hapreviously operated in a manner very similar the present-day system (1998) for whicdetailed information was available.
EXAMPLES OF SIMULATION RESULTS
Analysis of the proportionate contributionof water from wells and well fields to selectenetwork locations in the Dover Township areillustrates the increasing complexity anoperational variability of the distributionsystem throughout the historical period. A
16 Summary of Findings: Historical Reconstruction of the Water-Distribution System Serving the Dover Township Area, New Jersey: January 1962–December 1996
e
rte
ee
r
nd
nge
alice,hs
-lyD
es
previously described, these results wereobtained by conducting source-trace analysissimulations. The annual variation of thesimulated proportionate contribution of waterfrom all active wells and well fields to selectedlocations in the Dover Township area is shownfor the minimum-demand month of February(Figure 7), the maximum-demand months ofMay, June, July, or August (Figure 8), and theaverage-demand month of October (Figure 9).For each o f t hese examples , f i vegeographically distinct pipeline locations wereselected from the historical networks torepresent the spa t ia l d i s t r i bu t ion o fproportionate contribution results. Theselocations are identified on Figures 2 through 5,and Figures 7 through 9 as locations A, B, C,D, and E.
Comparison of the May 1962 results withthe June 1996 results (Figure 8), indicates theincreasing complexity of the network anddistribution-system operations and how suchoperations influenced the proportionatecontribution of water to specific locations. InMay 1962, only two well fields (Holly andBrookside) provided water to any one location;whereas, in June 1996, as many as seven wellfields provided water to the distribution system(for example, pipeline location E in Figure 8).
In Figures 7 through 9, the sum of theproportionate contribution of water from allwells and well fields to any pipeline locationshould be 100%. Because of numericalapproximation and roundoff, however, the totalcontribution from all wells and well fields maysum to slightly less or slightly more than 100%at some locations. This is expected when using
numerical simulation techniques. In thhistorical reconstruction analysis conductedfor the distribution system serving the DoveTownship area, the sum of the proportionacontribution at any location ranges from 98%to 101%.
In reviewing the simulation results, thannua l and seasona l va r ia t ion o f thproportionate contribution of water is evidentby inspecting, for example, the results fopipeline location D. Annual variation isdetermined by selecting a certain demacondition (minimum, maximum, or average—Figures 7, 8, or 9, respectively) and comparithe proportionate contribution results over thhistorical period (1962–1996). Seasonvariation is determined by choosing a specifyear and comparing the propor t ionatcontr ibution results for the minimum-maximum-, and average-demand mont(Figures 7, 8, and 9, respectively).
Simulation results for the maximumdemand months of May 1962, July 1971, Ju1988, and June 1996 for pipeline location exempl i fy the annual var ia t ion in thecontribution of water to this location andindicate the following (see Figure 8 for thproportionate contribution results and Figure2 through 5 for well and well field locations):
• May 1962—100% of the water wasprovided by the Brookside well (15);
• July 1971—30% of the water wasprovided by the Holly wells (14, 16, 18,19, and 21); 54% by the Brookside well(15); 3% by the Indian Head well (20);and 14% by Parkway wells (22, 23, 26,and 27);
Examples of Simulation Results 17
18 Summary of Findings: Historical Reconstruction of the Water-Distribution System Serving the Dover Township Area, New Jersey: January 1962–December 1996
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Examples of Simulation Results 19
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Holly Brookside (15) South Toms River Indian Head (20) Parkway Route 70 (31) Berkeley
Figure 7. Annual variation of simulated proportionate contribution of water from wells and well fields to selected locations in the Dover Township area, New Jersey, minimum-demand months, 1962–96.
Well or well field
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See full report for information on specific wells in operation. Number in paren-thesis is individual well number
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20 Summary of Findings: Historical Reconstruction of the Water-Distribution System Serving the Dover Township Area, New Jersey: January 1962–December 1996
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Examples of Simulation Results 21
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Holly Brookside (15) South Toms River Indian Head (20) Parkway Route 70 (31) BerkeleyWindsor (40)AnchorageSilver Bay
Figure 8. Annual variation of simulated proportionate contribution of water from wells and well fields to selected locations in the Dover Township area, New Jersey, maximum-demand months, 1962–96.
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See full report for information on specific wells in operation. Num-ber in parenthesis is individual well number. Anchorage and Silver Bay wells not assigned a number by water utility
22 Summary of Findings: Historical Reconstruction of the Water-Distribution System Serving the Dover Township Area, New Jersey: January 1962–December 1996
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Examples of Simulation Results 23
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Holly Brookside (15) South Toms River Indian Head (20) Parkway Route 70 (31) BerkeleyAnchorageSilver Bay
Figure 9. Annual variation of simulated proportionate contribution of water from wells and well fields to selected locations in the Dover Township area, New Jersey, average-demand months, 1962–96.
Well or well field
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henress
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• July 1988—49% of the water wasprovided by Holly wells (21 and 30); 26%by the Brookside well (15); 11% by theSouth Toms River wells (32 and 38); 14%by the Parkway wells (22, 23, 24, 26, 28,and 29); and 1% by the Berkeley wells(33-35); and
• June 1996—66% of the water wasprovided by the Holly well (30); 2% bythe Brookside well (15); 9% by the SouthToms River wells (32 and 38); 2% by theParkway wells (22, 24, 26, 28, 29, and42); 4% by the Berkeley wells (33-35),and 17% by the Windsor well (40).
The simulation results shown in Figures 7,8, and 9 demonstrate that the contribution ofwater from wells and well fields varied by timeand location. However, the results also showthat certain wells provided the predominantamount of water to locations throughout theDover Township area. Readers who areinterested in the proportionate contribution ofwater from specific water sources at specifiedtimes during the historical period of 1962through 1996 should refer to the full report.
SENSITIVITY ANALYSIS
The proportionate contribution resultsdescribed above were obtained from trace-analysis simulat ions conducted on thehistorical distribution-system networkswhereby balanced flow conditions wereachieved through the manual refinement ofmodeling parameters. The adjusted parameterswere the on-and-off cycling pattern values ofwells (pattern factor values assigned inEPANET 2) and the operational extremes ofwater levels in the storage tanks. This
modeling approach was designated as t“manual adjustment process.” Simulatioresults presented in this summary weobtained using the manual adjustment proceand were the bases of comparisons for sensitivity analyses.
To address the issue of uncertainty avar iab i l i ty o f sys tem operat ions, anspecifically to test the sensitivity of theproportionate contribution results to variationin model-parameter values, a technique wrequired that would “search” for and selectset of alternate operating conditions differefrom those determined using the manuadjustment process. These alternate operatcondit ions needed to also result in thsatisfactory operation of the historical watedistribution system. Such a technique wafound in the Genetic Algorithm optimization(GA) method. Simply put, a GA refers to method of optimization that attempts to finthe most optimal solution by mimicking (in acomputational sense) the mechanics of natuselection and natural genetics. (Aral et al.[2001] discuss GAs and their application twater-distribution system analysis; the fureport also presents additional references the development and application of GAs.)
Changes in simulated proportionatcontribution results were compared usinresu l ts ob ta ined th rough the manuaadjustment process and the GA approach. Tsensitivity analysis simulations were groupeinto three categories (Figure 10): (1) variatioo f pa t te rn fac tors ass igned to we l l(operational variation in the value and the timof day—designated as sensitivity simulation
24 Summary of Findings: Historical Reconstruction of the Water-Distribution System Serving the Dover Township Area, New Jersey: January 1962–December 1996
alyrer8,s,re,s.tois
SENS0, SENS1, SENS2, and SENS3); (2)variation in the operational minimum pressurecriteria at pipeline locations (designated assensitivity simulations SENS4 and SENS5);and (3) variation in the operational storagetank water-level differences between thestarting time (0 hours) and ending time (24hours) o f a s imulat ion (des ignated assensitivity simulations SENS6 and SENS7).Sensitivity analysis simulation SENS0 andSENS1 applied the GA approach to everyhistorical network (420 simulations) using thebalanced flow conditions obtained from the
manual adjustment process as the initistarting conditions. The remaining sensitivitanalysis simulations (SENS2–SENS7) weconducted for distribution-system networks foselected years of 1962, 1965, 1971, 1971988, and 1996. For these historical networkthe previously described parameters wevar ied wi th respect to the min imum-maximum-, and average-demand monthReaders desiring specific details pertaining the definition of each of the sensitivity analyssimulations should refer to the full report.
Sensitivity Analysis 25
0 5 10 15 20 25 300
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ABSOLUTE VALUE OF DIFFERENCE IN SIMULATED CONTRIBUTION OF WATERBETWEEN MANUAL ADJUSTMENT PROCESS AND GENETIC ALGORITHM
OPTIMIZATION, IN PERCENT CONTRIBUTION
Figure 10. Results of sensitivity analyses using the manual adjustment process and Genetic Algorithm (GA) optimization for maximum-, minimum- and average-demand months, 1978.
SENSITIVITY ANALYSIS SIMULATIONS, 1978
(1) n=number of study locations where the contribution of water is greater than 0 percent
(2) See complete report for specific details on definitions of sensitivity analysis simulations
(3) Study locations provided by New Jersey Department of Health and Senior Services without personal identifiers and status
SENS0 6,004
SENS1 6,061
SENS2 5,963
SENS3 5,950
SENS4 5,988
SENS5 6,021
SENS6 6,102
SENS7 6,138
Notes
Minimum pressure criteria
Difference between startingand ending storage-tank water-level in a 24-hour period
Well-pattern factors
nSimulation
identification Parameters varied
lal6d
20e
ed
se-ine)e,
fre
rsy
mddr
rtr-r
leye
ot
Figure 10 shows examples of results forthe sensitivity analysis simulations represent-ing 1978 conditions. These results indicatesmall variations when comparing the propor-tionate contribution results from the manualadjustment process to results obtained usingthe GA approach. Figure 10, however, alsoshows that the simulated proportionate contri-bution of water from wells and well fields isrelatively insensitive to changes in systemoperational parameters. For a 24-hour period,the average percentage of water over all studylocations derived from all wells or well fieldsusing either the manual adjustment process orany of the GA simulations does not varyappreciably. For example, the results in Figure10 indicate that more than 90% of study loca-tions show a difference of 10% or less in thesimulated proportionate contribution resultsderived from either the manual adjustment pro-cess or any of the GA simulations. Theseresults (Figure 10) indicate that there was anarrow range within which the historicalwater-distribution system could have success-fully operated to maintain a balanced flow con-dition and satisfy the “Master OperatingCriteria” previously described. Results forother historical networks (such as 1988 and1996) show less variation when comparingsimulated proportionate contribution resultsobtained using either the manual adjustmentprocess or any of the GA optimizationapproaches.
For the historical reconstruction analysis,investigators assumed that daily systemoperations over a period of 1 month could berepresented by a “typical” 24-hour day foreach month of the historical period. To test the
val idi ty of this assumption, addit ionasensitivity analyses using hourly operationdata obtained from the water utility for 199were conducted. For the maximum-demanmonth of June 1996, a 30-day analysis—7hours—was conducted by simulating thhourly operation according to the data suppliby the water utility. When results for thehourly operation simulation for 30 day(average over the 30-day period) wercompared with results from the “typical” 24hour day for the month of June, differences the proportionate contribution of water to thfive pipeline locations (A, B, C, D, and Eshowed only slight variations. As an examplthe difference in the contribution of water fromthe Parkway well field for the two methods osimulating the daily system operations we0% for location A, 1% for location B, 4% forlocation C, 2% for location D, and 3% folocation E. Therefore, sensitivity analysiassisted in confirming that the day-to-daoperations of the water-distribution systewere highly consistent over a 30-day perio(based on available 1996 hourly data) ancould be represented by a “typical” 24-houoperational pattern.
The sensitivity analysis conducted as paof the historical reconstruction of the watedistr ibut ion system serving the DoveTownship area indicate that: (1) there was anarrow range within which the historicawater-distr ibut ion systems could havsuccessful ly operated and st i l l sat isfhydraulic engineering principles and th“Master Operating Criteria,” and (2) dailyoperational variations over a month did nappreciably change the propor t ionate
26 Summary of Findings: Historical Reconstruction of the Water-Distribution System Serving the Dover Township Area, New Jersey: January 1962–December 1996
. acfl-
.r2.
.s1,
c.l-).
sg-
n
,r-tfnt
l.
ch
.ers
contribution of water from specific sourceswhen compared to a typical 24-hour dayrepresen t ing the mon th . Thus , t hereconstructed historical water-distributionsystems and operating criteria—based onapplying the “Master Operating Criteria” andusing generalized water-utility information—are believed to be the most probable andrealistic scenarios under which the historicalwater-distribution systems were operated.
REFERENCESAgency for Toxic Substances and Disease Registry
(ATSDR). 2001a. Health consultation, drinkingwater quality analyses, March 1996 to June1999, Uni ted Water Toms River, DoverTownship, Ocean County, New Jersey. Atlanta:Agency for Toxic Substances and DiseaseRegistry.
Agency for Toxic Substances and Disease Registry(ATSDR). 2001b. Public health assessment forCiba-Geigy Corporation, Dover Township,Ocean County, New Jersey, EPA facility ID:NJD001502517. Atlanta: Agency for ToxicSubstances and Disease Registry.
Agency for Toxic Substances and Disease Registry(ATSDR). 2001c. Public health assessment forDover Township Municipal Landfill (a/k/aDover Township Landfill), EPA facility ID:NJD980771570 and Silverton private wellcontamination investigation (a/k/a Silvertonwells), EPA facility ID: NJD981877780, DoverTownship, Ocean County, New Jersey. Atlanta:Agency for Toxic Substances and DiseaseRegistry.
Agency for Toxic Substances and Disease Registry(ATSDR). 2001d. Public health assessment forReich Farm, Dover Township, Ocean County,New Jersey, EPA facility ID: NJD980529713.Atlanta: Agency for Toxic Substances andDisease Registry.
Aral MM, Guan J, Maslia ML, Sautner JB. 2001Reconstruction of hydraulic management ofwater-distr ibution system using genetialgorithms. Atlanta: Georgia Institute oTechnology, Mult imedia EnvironmentaSimulations Laboratory Report No. MESL0101.
Board of Public Utilities, State of New Jersey1962. Annual report of Toms River WateCompany, year ended December 31, 196Newark (NJ): Board of Public Utilities.
Board of Public Utilities, State of New Jersey1996. Annual report of United Water TomRiver Company, year ended December 31996. Newark (NJ): Board of Public Utilities.
Flegal GJ. 1997. United Water Toms River, InLetter to Barker Hamill from George J. Flegaconcerning hydraul ic model and waterdistribution system data. Toms River (NJMarch 27, 1997.
Maslia ML, Sautner JB, Aral MM. 2000a. Analysiof the 1998 water-distribution system servinthe Dover Township area, New Jersey: fielddata collection activities and water-distributiosystem modeling. Atlanta: Agency for ToxicSubstances and Disease Registry.
Maslia ML, Sautner JB, Aral MM, Reyes JJAbraham JE, Williams RC. 2000b. Using wated is t r ibu t ion sys tem model ing to assisepidemiologic investigations. ASCE Journal oWater Resources Planning and Manageme126(4):180-98.
Rossman LA. 2000. EPANET 2 users manuaCincinnati: US Environmental ProtectionAgency, National Risk Management ResearLaboratory.
Toms River Chemical Corporat ion. 1966Memorandum to R.K. Sponagel from P. Wehnconcerning the water supply situation. TomRiver (NJ). March 21, 1966.
References 27
atllick...
V.
dey);
ipnlf
tal.
d;
eE.he,g.
kithr-asalngforon.
.terd
t.ed
d,
nd
PRINCIPAL INVESTIGATORS, CONTRIBUTORS, AND ACKNOWLEDGEMENTS
Principal Investigators
MORRIS L. MASLIA, MSCE, PEResearch Environmental Engineer and
Project OfficerExposure-Dose Reconstruction ProjectDivision of Health Assessment and ConsultationAgency for Toxic Substances and Disease Registry
JASON B. SAUTNER, MSCE, EITEnvironmental Health Scientist
Division of Health Assessment and ConsultationAgency for Toxic Substances and Disease Registry
MUSTAFA M. ARAL, Ph.D., PE, PHyDirector, Multimedia Environmental Simulations
LaboratorySchool of Civil and Environmental EngineeringGeorgia Institute of Technology
Contributors
RICHARD E. GILLIG , MCPSupervisory Environmental Health Scientist
Chief, Superfund Site Assessment BranchDivision of Health Assessment and ConsultationAgency for Toxic Substances and Disease Registry
JUAN J. REYES, MSPAProgram Manager
Director, Office of Regional OperationsOffice of the Assistant AdministratorAgency for Toxic Substances and Disease Registry
ROBERT C. WILLIAMS , PE, DEEAssistant Surgeon General
Director, Division of Health Assessment and Consultation
Agency for Toxic Substances and Disease Registry
AcknowledgementsThe authors acknowledge their colleagues
ATSDR for providing assistance and advice with aaspects of this investigation: John E. Abraham, PatrBrady, James A. Clark, Amy B. Funk, Amanda JGonzalez, Virginia Lee, Susan Metcalf, Thomas AMignone, Jennifer Noack, Mary G. Odom, Sven ERodenbeck, Kevin A. Ryan, Kathy Skipper, Gregory Ulirsch, and Ann Walker.
The following organizations and their staff providesuggestions, assistance, or information: New JersDepartment of Health and Senior Services (NJDHSSOcean County Health Department; Dover TownshMunicipal Government; Citizens Action Committee oChildhood Cancer Cluster; Multimedia EnvironmentaSimulations Laboratory at the Georgia Institute oTechnology; New Jersey Department of EnvironmenProtection; New Jersey Geological Survey; U.SEnvironmental Protection Agency, Region II; UniteWater Toms River, Inc.; Union Carbide Corporationand Ciba-Geigy Corporation.
The authors would like to specifically acknowledgJerald A. Fagliano, Michael Berry, and Jonathan Savrin of NJDHSS for suggestions and advice from tepidemiologic perspective; Michael J. McLindenformerly with NJDHSS, for assistance in obtaininhistorical production data; Lewis A. Rossman, U.SEnvironmental Protection Agency, Nat