XCG File #1-1751-01-02 - Bay of Quinte Remedial Action Plan

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XCG File #1-1751-01-02 - Bay of Quinte Remedial Action Plan
XCG
EXCELLENCE IN
ENVIRONMENTAL
CONSULTING
SERVICES
XCG File #1-1751-01-02
May 25, 2005
TECHNICAL MEMORANDUM
BAY OF QUINTE
DRINKING WATER
TASTE AND ODOUR SURVEY
Prepared for:
BAY OF QUINTE REMEDIAL ACTION PLAN RESTORATION COUNCIL
714 Murray Street, RR#1
Trenton, ON K8V 5P4
Attention: Mr. Barry Jones
XCG Consultants Ltd.
33 Earl Street
Kingston, ON
Canada
K7L2G4
Tel: (613) 542-5888
Fax: (613) 542-0844
E-mail:
[email protected]
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Bay of Quinte Drinking Water Taste and Odour Study
TECHNICAL MEMORANDUM
EXECUTIVE SUMMARY
The Bay of Quinte Remedial Action Plan Restoration Council has commissioned this study in an
effort to determine whether taste and odour problems in Bay of Quinte drinking water still
constitute an impaired beneficial use (mU). Note: the International Joint commission (IJC)
website, uses the terminology BUI (Beneficial Use Impairment).
Taste and Odour was identified as one of ten mus in the Bay of Quinte
Remedial Action Plan (Bay of Quinte Coordinating Committee, 1993).
The condition was then associated with high levels of nutrients and algae.
A recent study (Quinte Conservation, 2003) failed to find a sufficient reduction in nutrient levels
(total phosphorous) to reach the conclusion that taste and odour problems no longer constitute an
mu. The report recommended a survey of end users to obtain their perception of municipal
drinking water taste and odour. The purpose of the present study was, therefore, to survey
customers of municipal drinking water supplies in the Bay of Quinte to determine whether this
continues to be an mu.
Initially, the municipalities of Qninte West (Bayside), Belleville and Deseronto were identified.
Subsequently, Picton was added. The results of the survey and water treatment plant comparison
are described in this report.
A telephone survey was designed which included questions regarding the length of time the users
had lived at their present location and whether they drank the water untreated. As well, XCG
obtained water distribution maps and located the respondent as either near the water plant or at
the extremity since water quality changes throughout the distribution system.
A total of 30 complete responses were considered an adequate sample size for each surveyed
municipality; however, in the case of Belleville, additional responses were obtained, for a total of
47. Therefore, for the four municipalities, a total of 137 survey responses were obtained.
Of the total number of respondents across the four municipalities, 59 identified taste and odour
as an issue. At 43% of the total respondents, this is a significant number. However, of the 59
several (7) nO longer have a problem and a significant number of the remaining 52 report
chlorine as the source of the taste and odour. The highest incidence of taste and odour complaints
was found in the municipalities of Belleville and Picton, with a lower incidence rate in Deseronto
and Quinte West (Bayside). In Belleville, more than half (53%) of the respondents reported
issues with taste and odour in their drinking water. However, it should be noted that the survey
found most complaints related to chlorine, rather than the taste and odour associated with the
presence of organics.
As part of this stndy, visits Were made to four municipal water treatment plants in order to
document installed equipment, processes and procedures and to note any taste and odour
complaints received by plant staff.
From the plant visits it is evident that there are equipment and treatment methods in place to deal
with taste and odour issues. The Belleville and Bayside plants are now 'state of the art', making
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TECHNICAL MEMORANDUM
any comparison with earlier reports of taste and odour problems meaningless. The Deseronto
plant however has changed little since the original construction in 1976.
From an examination of the survey data, the study concluded that taste and odour impairment of
drinking water in the Bay of Quinte is not a restored beneficial use.
From an examination of water plant equipment and operations, there is no obvious evidence of
an mu. The equipment in place in the plants visited is no more extensive or elaborate than that
elsewhere in the Great Lakes. Similarly operations such as the addition of powder activated
carbon (PAC) are not unusual. However, the processes in place have not resulted in the
elimination of, or a reduction in taste and odour problems, therefore the issue of mu remains.
The results of the survey suggest that the taste and odour problems at all plants were currently
not a major concern to the respondents and not dissimilar to reports from other communities
bordering the Great Lakes. Therefore, while the mu continues, further investment in process
change may not be warranted from a costlbenefit or health perspective unless the presence of
harmful substances becomes evident.
II
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TABLE OF CONTENTS
Executive Summary ......................................................................................................................... i
Table of Contents ........................................................................................................................... iii
Figures ............................................................................................................................................ iii
Appendices ..................................................................................................................................... iii
1.
INTRODUCTION .................................................................................................................... 1
2.
BACKGROUND ......................................................................................................................2
2.1
3.
Assessment of the Bay of Quinte Taste and Odour Impaired Beneficial Use ........ 3
TASTE AND ODOUR SURVEY ...............................................................................................4
3.1
Task 1: Results of User Survey ................................................................................5
3.2
Task 2: Water Plant Visits ....................................................................................... 8
4.
TASTE AND ODOUR ISSUES IN THE GREAT LAKES ........................................................... 14
5.
CONCLUSIONS .................................................................................................................... 15
6.
RECOMMENDATIONS ••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••• 15
7.
REFERENCES ...................................................................................................................... 16
FIGURES
Figure 1
Figure 2
Figure 3
Figure 4
Figure 5
1996 to 2001 Phosphorus Levels ............................................................................ 4
Chemical Usage ...................................................................................................... 4
Identification of Taste and Odour in Municipal Drinking Water ........................... 6
Improvement in Taste and Odour in Municipal Drinking Water ........................... 7
Numbers with Improved Water Quality with Additional Treatment.. .................... 8
ApPENDICES
Appendix A
Appendix Bl
AppendixB2
AppendixB3
AppendixB4
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Telephone Survey Form
Belleville Survey Results
Picton Survey Results
Deseronto Survey Results
Quinte West (Bayside) Survey Results
iii
Bay of Quinte Drinking Water Taste and Odour Study
TECHNICAL MEMORANDUM
1.
INTRODUCTION
The Bay of Quinte Restoration Council has commissioned this study in an effort to
detennine whether taste and odour problems in Bay of Quinte drinking water still
constitute an impaired beneficial use (IBU). Note: the International Joint commission
(Ile) website, uses the terminology BUI (Beneficial Use Impairment).
Taste and Odour was identified as one of ten IBUs in the Bay of Quinte Remedial Action
Plan (Bay of Quinte Coordinating Committee, 1993). The condition was tben associated
with high levels of nutrients and algae. The 1993 report set the goal:
To restore and maintain the trophic status of the Bay of Quinte so that
phytoplankton densities are reduced, taste and odour problems in drinking
water are improved and the trophic status of the bay is similar to the
1930s condition.
l
A recent study (Quinte Conservation, 2003) failed to find a sufficient reduction in
phosphorous levels to reach the conclusion that taste and odour problems no longer
constitute an IBU. The report recommended a survey of end users to obtain their
perception of municipal drinking water taste and odour. The purpose of tbe present study
is, tberefore, to survey customers of municipal drinking water supplies in the Bay of
Quinte to determine whether this continues to be an IBU.
In 1991, tbe International Joint Commission approved guidelines for delisting Areas of
Concern. The intent of these guidelines was to serve as an initial reference point on which
to base the development of appropriate restoration criteria (UC, 2004a). The guidelines
for drinking water consumption were as follows:
L.
1. when densities of disease-causing organisms or concentrations of hazardous or toxic
chemicals or radioactive substances do not exceed human health objectives, standards
or guidelines;
2. when taste and odour problems are absent; and
3. when treatment needed to make raw water suitable for drinking does not exceed the
standard treatment used in comparable portions of the Great Lakes which are not
degraded (i.e., settling, coagulation, disinfection).
In order to be satisfied that any remaining taste and odour problem is not simply a
process or equipment problem, the study includes visits to each of the Bay of Quinte
water plants to document equipment and processes.
Since 1991, local RAP groups have developed restoration targets for tbeir Areas of
Concern. In the Bay of Quinte, the IBU Delisting Target related to restrictions on
drinking water consumption is as follows (UC, 2004b):
Maintain all treated drinking water supplies in compliance with
Provincial Drinking Water Objectives and improve the palatability of
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Bay of Quinte Drinking Water Taste and Odour Study
TECHNICAL MEMORANDUM
drinking water drawn from the bay by reducing the biomass of taste and
odour causing algae.
2.
BACKGROUND
Taste and odour problems can be caused by the presence of a number of compounds in
the raw water:
•
organisms including phytoplankton which can produce methyl-iso-bomeal (MID),
geosmin and tricholoro-anisole
•
phenols
•
benzene compounds
•
trihalomethanes (THM)
•
other (rarer) organic compounds
•
chlorine
The level for human detection varies and is generally much lower than drinking water
standards. For example, geosmin can be detected at 2.0 ppt, MID at 4 ppt, yet the safe
limits are many times these levels. A common description of their presence is an earthy
or musty flavour or odour.
There is also evidence that zebra mussels contribute to taste and odour problems either by
causing changes in the phytopolankton community or through faeces (L'ltalien et al,
1998).
The presence of taste and odour in water supplies is increasing in many areas including
the Great Lakes. The offending compounds are produced by organisms such as algae,
bacteria, fungi, and protoza (Charlton et al, 2000). While high nutrient levels are known
to contribute to algae blooms and to the production of these compounds, recent
occurr~nces in the Great Lakes have been with low nutrient levels.
While taste and odour appears to be linked to the organisms noted above there is
inadequate knowledge regarding triggers or actual source. Because the source could be
living species or sediments residing on the bottom or washed into the area of the intake it
is difficult to predict occurrences or causes. Additionally, conditions such as temperature,
water clarity, the presence of new species (eg. Zebra mussels) and shifts in species
population make it difficult to attribute taste and odour to elevated nutrient levels.
In the Bay of Quinte, the' major source of the problem in early years has been nutrient
enrichment leading to excessive algae production. The literature documents this problem
from the early 1900s to the 1980s when a combination of phosphorus reduction and
improved water treatment resulted in an improvement in drinking water quality (MOE,
1986). It is recognized, however, that the trophic status of the Bay of Quinte is complex
and depends on the inter-relationship among algae, algae-eaters (zooplankton and benthic
organisms) and eaters of algae-eaters (fish).
2
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In choosing the 1930's as an acceptable trophic state, the Bay of Quinte RAP may have
picked a target that is difficult to benchmark. There is evidence that the bay was in a
highly trophic state by 1904 (MOE, 1986). Problems with algae clogging filters and
causing odour were encountered at the Belleville water treatment plant throughout the
1930s. By 1958 renovations including the addition of microstrainers were necessary to
deal with the algae.
A considerable improvement in the trophic status of the bay beginning in 1977 was noted
after the implementation of the ban on phosphorus detergent and improvements in
sewage treatment. .
2.1
Assessment of the Bay of Quinte Taste and Odour Impaired Beneficial Use
As discussed previously, the 2003 Quinte Conservation study concluded that nutrient
levels have not been reduced to levels low enough to eliminate algae production
constituting an on-going problem for raw water treatment of drinking water.
The study reviewed the delisting targets and objectives used to measure whether the
targets had been met:
Objective #1: A reduction in algae levels from the base year levels (1989-1994) as
anticipated by reduced phosphorous concentrations in the upper Bay of Quinte in the raw
water intake at the Belleville water treatment plant.
Objective #2: Fewer taste and odour complaints compared to the base year period in the
Belleville, Deseronto and Bayside drinking water supplies.
Objective #3: A reduction in chemical usage from the base year levels as anticipated by
reduced phosphorous concentrations in the upper Bay of Quinte at the Belleville,
Deseronto and Bayside water treatment plants.
Objective #4: No Ontario Drinking Water Surveillance Program Maximum Exceedence
Levels (ODWSP MAC) exceedences reported since 1993. No significant increase in
trihalomethane (THM) levels in May of Quinte drinking water from the levels reported in
the 1993 Bay of Quinte State 2 Report.
Objective #5: No safe level exceedences of THM in Bay of Quinte drinking water at the
noted DWSP sampling sites.
Extensive analysis was performed on the historical data; as an example Figure 1 below is
taken from the 2003 report. It indicates that phosphorous levels are not declining. In
another section, chemical usage at water plants (Figure 2) is examined and again no
decline is in evidence. Other factors may however explain the result. For example, more
chlorine has been used since the Walkerton incident in order to maintain higher residuals.
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Phosphorus Levels in Bay of Quinte
Source: DWSP
0.06
I \
0.051
0.041
con~:;~tion::1 ~~
.
jP-S::Ll
.
/
~
0.01
F\
"
1-1-------------------1989
1990
1991
1992
1993
1994
1995
1996
1997
1998
1999
2000
2001
Year
Figure 1
1996 to 2001 Phosphorus Levels
- - - - - - - ' 1 4.5
00.0
4
,.,
i§;
40.0
.§.
II
r ""
r
c:
,., I--Bell-Alum
~
.......... Deser ~ Chlorine
........... S611- Chlorine
B
8c
20.0
rl---------
---------------+11.'
1O.0t-1----------------------j
0.'
0.0
I
1988
f 0
1990
1992
1994
1996
199B
2000
2002
Year
Figure 2
Chemical
Usage
r. . - '
The report could not find data to support progress on this objective (Objective #2: Fewer
Taste and Odour Complaints), and for that reason the present study was recommended.
3.
TASTE AND ODOUR SURVEY
The Bay of Quinte RAP Request for Proposals included the following tasks:
4
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TECHNICAL MEMORANDUM
1. Design a survey to assess public perceptions of municipal drinking water taste and
odour as those perceptions have or have not changed since circa 1990. Conduct the
survey, evaluate the results and draft a report. The report is to also include complaints
of taste and odour received by water treatment plant staff.
2. A brief comparison of water treatment plant processes/technologies used in the upper
Bay of Quinte with those processes/technologies considered "standard" in the
treatment industry. The objective is to determine if there are any special or additional
measures being used by local treatment plants in the Bay to combat algae and
associated taste and odour problems.
Initially, the municipalities of Quinte West, Belleville and Deseronto were identified.
Subsequently, Picton was added. The results of the survey and water treatment plant
comparison are described in this report.
f..
3.1
Task 1: Results of User Survey
A telephone survey was designed (see Appendix A) to be administered to water
customers served by the water utilities in their respective communities The survey
included questions regarding the length of time the user had lived at his/her present
location and whether he/she drank the water untreated. As well, XCG obtained water
distribution maps and located the respondent as either near the water plant or at the
extremity since water quality changes throughout the distribution system. For example,
chlorine is more likely detected near the plant, colour and sediment at the extremities of
the system.
A total of 30 complete responses were considered an adequate sample size for each
surveyed municipality; however, in the case of Belleville, additional responses were
obtained, for a total of 47. Therefore, for the four municipalities, a total of 137 survey
responses were obtained.
Complete survey results are included in Appendix B. Summary graphics were produced
to illustrate the results.
For each of the municipalities, the number of respondents who had ever identified taste
and odour as an issue with their drinking water were determined. These are presented in
Figure 3, both as a percentage of total respondents, and in absolute numbers.
TMl17510102F_o50525
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TECHNICAL MEMORANDUM
~,--T~----'~---'
20
20
rONal
~
10%
0%
I
(>'"
',,,
Belleville
Figure 3
'i,'1
Picton
;1
Deseronto
1";"1
Quinte West
Identification of Taste and Odour in Municipal Drinking Water
The highest incidence of taste and odour complaints was found in the municipalities of
Belleville and Picton, with a lower incidence rate in Deseronto and Quinte West. In
Belleville, more than half (53%) of the respondents reported issues with taste and odour
in their drinking water. Of the total number of respondents across the four municipalities,
59 identified taste and odour as an issue. At 43% of the total respondents, this is a
significant number.
A significant number (61 % of all respondents) report chlorine as the nature of the taste
and odour. In Picton and Quinte, most (more than 90%) of the complaints related to
chlorine. In Deseronto, half the respondents identified chlorine as the source of the taste
and odour problems. In Belleville, 36% of the complaints were related to chlorine.
Generally, of those respondents who did not mention chlorine as the major issue, the
complaint was of a "musty" or "swampy" taste and/or odour, likely the result of elevated
algae levels. Therefore, taste and odour issues can be partly related to algae in Deseronto
and Belleville, but not in Picton and Quinte, where the vast majority of complaints are
related to chlorine.
For the 59 respondents who did identify taste and odour in their water, the question was
asked whether taste and odour continues to be a problem. The results are illustrated in
Figure 4, again as both a percentage and absolute number of respondents.
6
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TECHNICAL MEMORANDUM
100% -
'~-'~"~~~"~~-'-r---r--------r-----"I-~---------'-'---------'
90%
80%
70%
..
...,
~
'tJ
t::
0
Q.
a:
'0
..,.
60%
50%
I
<i J------j
40%
DYes I
0 No
30%
20%
("
10%
0%
Belleville
Figure 4
Picton
Deseronto
Quinte West
Improvement in Taste and Odour in Municipal Drinking Water
For each municipality, the results are quite consistent; a range of 80 to 90% of the
respondents who identified taste and odonr in their drinking water in the past still
consider it to be an issue. As a whole, 52 of the respondents (38% of those surveyed) are
still experiencing taste and odonr problems.
L
t.
Only seven respondents who had experienced taste and odour issues in the past reported
an improvement in their water quality. As illustrated in Figure 5, of these, almost half
(three respondents) had added treatment to their water system, such as filtering, that may
have contributed to the improved taste and odonr. Only four of the respondents (two in
Belleville, and one in each of Deseronto and Quinte West) reported improved water
quality without additional treatment. These may be attributable to the general
improvement in Bay of Quinte raw water qUality.
~117510102F_050525
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Bay of Quinte Drinking Water Taste and Odour Study
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100% .
~"-'-'-'~-"-"-r-----l
90%
80%
2
70%
J!l
i
~
60%
50%
1
I ".I
'0
....
I DYes
r
30%
-l---------I i ,:
20%
+--I':P";'
0%
I
F"
,'I
Belleville
Figure 5
I
•
Picton
F"; ,
1
Deseronto
1--1
F;;'; ';, 1
Quinte West
I
DNo
;1
Total
Numbers with Improved Water Quality with Additional Treatment
The water survey results lend some support to the conclusions reached by Quinte
Conservation (2003), but generally only in Belleville and Deseronto. In these
municipalities, the survey results suggest that there has not been a reduction in taste and
odour causing algae. In Picton and Quinte, the taste and odour complaints are dominated
by chlorine, so no conclusions can be reached about any possible reduction in taste and
odour causing algae. Regardless of the nature of the complaint, with 30 to 50% of
respondents reporting a problem with taste and odour in their drinking water, and only
approximately 10% reporting any improvement, it is evident that drinking water is still
impaired in the Bay of Quinte.
Therefore taste and odour problems in Bay of Quinte drinking water still constitute an
mu; further progress is required to delist the Bay based on the 1989-1994 base year
target.
3.2
Task 2: Water Plant Visits
As part of this study, visits were made to four municipal water treatment plants. The
purpose of the visits was to:
I. Document installed' equipment, processes and procedures to determine whether the
plant operation is typical of a Great Lakes water source plant or whether specialized
equipment is in place to deal with taste and odour problems.
2. Record any taste and odour problems received by plant staff.
The results ofthe plant visits are summarized below.
8
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Bayside
Owned and operated by the Municipality of Quinte West
Contact: Mr. Steve McDonald, Manager of Plants
Date of Visit: September 9, 2004
Plant Description:
The Bayside water treatment plant is a fairly new facility (1995) with a
capacity of 11,300 m 3/d. However, the current water demand is less than
half of the plant capacity; the plant is usually in operation for about 8
hours per day.
The intake is 370 m long. The original treatment plant design included
manual screens and a travelling screen, a micros trainer for algae removal,
ozone, coagulation, three-stage flocculation, sedimentation, filtration
through anthracite/sand filters and granular activated carbon (GAC)
contactors. Both ozone and GAC provide taste and odour control.
Chlorine is used for disinfection (inactivation).
The microstrainer has not been in use since the City of Quinte West took
over operation of the plant. The ozone is also no longer used, and the
owner is applying to have ozone removed from the Certificate of
Approval.
Chemicals Used:
• Coagulant - Alum
TMl17510102F_o50525
•
Chlorine (sodium hypochlorite) - used for disinfection inactivation,
not used for zebra mussel control
•
Fluoride - hydrofluosilicic acid
9
Bay of Quinte Drinking Water Taste and Odour Study
TECHNICAL MEMORANDUM
Comments from Staff (Taste&Odour, Raw Water, Operations, Chemical
Use):
The travelling screen is currently out of service; the manual screens are
cleaned only about twice per year, indicating that algae build-up on the
screens is not a problem. The lack of use of the microstrainer is also an
indication that the concentration of algae in the raw water is low. The
filters are backwashed twice per week, usually based on time in service
rather than headloss or turbidity breakthrough.
The GAC has not been changed since the plant was commissioned (9
years), and is due to be changed next year. The current owners have not
needed to use the ozone system.
The operator reported that very few taste and odour complaints are
received, and rarely is there a repeat complaint from the same consumer.
10
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Belleville
Owned and operated by the City of Belleville
Contact: Mr. Bob McKeown, Water Treatment Plant Superintendent
Date of Visit: November 5, 2004
Plant Description:
The Belleville plant is only four years old and was constructed on the site
of the old plant at Sidney Street. The plant has a capacity of 72
megalitres; current maximum day demand is 34 . Twin intakes take water
from a depth of about 8 metres and deliver water through a screen and
low lift pumps to coagulant contact tanks. Water then flows to dissolved
air flotation (DAF) tanks that operate during the ice-free (Bay of Quinte)
period. The next clarifying process is a series of tanks with laminar
plates. This facility is used in place of the DAF process in winter months
when suspended solids are low. Sand filters topped with granular
activated charcoal (GAC) complete the treatment. Water is then
chlorinated and sent into the delivery system. Post chlorination greatly
reduces the formation of chlorinated organics such as trihalomethanes
(THM).
The plant is extremely well run, appears to produce an excellent product
and should have few issues with taste and odour. Plant staff do perform
threshold odour tests and the results are typically 1.
Chemicals Used:
•
Coagulant - Alum
•
Chlorine (sodium hypochlorite) - used for disinfection and for zebra
mussel control
•
Potassium permanganate-used infrequently for zebra mussel control
(also beneficial for taste and odour)
Fluoride - hydrofluosilicic acid
Comments from Staff (T&O, Raw Water, Operations, Chemical Use):
Few complaints received (5-6 per year), usually chlorine detected or
distribution issues such as colour or sediment. Staff feel that most
customer complaints are comparing city water with bottled water the
main difference being the presence of chlorine in the city water.
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Bay of Quinte Drinking Water Taste and Odour Study
TECHNICAL MEMORANDUM
Deseronto
Owned by Town of Deseronto and operated by Greater Napanee Utilities
Contact: Mr. Max Christie, Manager
Date of Visit: September 9,2004
Plant Description:
The Deseronto Water Treatment Plant has a rated capacity of 2,900 m3/d;
the current average flow is approximately 1,300 m 3/d.
The treatment processes include coagulation, flocculation/clarification
(Eimco Reactivator clarifier), and filtration through dual media anthracite
and sand filters. Two granular activated carbon (GAC) contactors, in
parallel, are used at all times for taste & odour control. Chlorine is used
for disinfection (inactivation).
Raw water turbidity is usually 2 to 3 NTU, with high of about 20 NTU.
Chemicals Used:
• Coagulant - Eaglebrook PASS-C (polyaluminum chloride), lIO-130
mg/L
•
•
Coagulant aid - Nalco Optimer 7199, -1 mgIL
Chlorine - used for zebra mussel control when required, and for
primary and secondary disinfection
Soda Ash was previously used for pH control, but not currently needed
with PASS-C coagulant
Comments from Staff (T&O, Raw Water, Operations, Chemical Use):
It is not known when the GAC in the contactors was last changed. The
current owners/operators have not changed the GAC since they took over
the plant in January 2003.
No taste and odour complaints have been received. Complaints are
usually related to coloured water due to cast iron watermains.
12
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Picton
Owned and operated by Prince Edward County
Contact: Mr. Bryan Robson, Environmental Services Manager
Date of Visit: September 9, 2004
Plant Description:
The plant rated capacity is 10,400 m 3/d; the current average flow is
approximately 4,300 m3/d with high flows up to 7,000 m 3/d. The intake
is at a depth of approximately 3 m. Another (older) intake is available as
a back-up.
(:
The treatment processes consists of coagulation, 3-stage hydraulic
flocculation, sedimentation, filtration and disinfection. Powdered
activated carbon (PAC) is used for taste & odour control. Fluoride is also
added to the treated water. Chlorine is added at the mouth of the intake
structure for zebra mussel control when the raw water temperature is
above 12°C.
Chemicals Used:
•
Coagulant - General Chemical Clarion A405T, 30 mg/L (proprietary
coagulant)
•
PAC - maximum dose of approximately 6 mgIL (110 kg/5 days)
•
Chlorine - used for zebra mussel control, primary and secondary
disinfection
•
Fluoride - hydrofluosilicic acid
,i
Comments from Staff (T&O, Raw Water, Operations, Chemical Use):
Two manual raw water screens are cleaned every day. In summer, they
tend to be covered with a brown slime that looks to be combination of
seaweed and silt. The wind direction has an impact on the amount of
material on the screens. In winter the screens are cleaner.
The PAC has been able to control taste and odour in 2004. In 2003, the
algae levels were higher, and the PAC could not be added at a high
enough ,dose to control the taste and odour. The PAC system is to be
upgraded this fall to enable a higher dose to be used.
The operators feel the taste and odour problems are increasing. Ten years
ago, the plant did not have to deal with algae blooms, but they now occur
every year.
TM117510102F_o50525
13
Bay of Quinte Drinking Water Taste and Odour Study
TECHNICAL MEMORANDUM
From the plant visits it is evident that there is adequate equipment and treatment methods
in place to deal with taste and odour issues. The Belleville and Bayside plants are now
'state of the art', making any comparison of earlier reports of taste and odour problems
meaningless. However, neither of the taste and odour control systems at Bayside are
being used; ozone is not used at all, and the GAC is so old that it is probably ineffective.
The presence of the micros trainer indicates that algae must have been a problem, or
perceived to be a problem, when the plant was designed. It is significant to note that
neither Belleville nor Bayside utilize strainers now; they are not needed and these plants
are located in the upper reach of the Bay where nutrient problems have been more severe.
The Deseronto plant however has changed little since the original construction in 1976.
The GAC contactors have been used continuously, although the improvement to taste and
odour by the contactors has not been assessed
The operators at the Picton WTP believe that the taste and odour problems are worsening.
The PAC system is being upgraded to allow higher dosages of PAC to respond to tastes
and odours. The plant intake is in very shallow water and while the nutrient levels may be
lower in this part of the Bay of Quinte, weeds and sediments are problems when
disturbed by wave action.
The study results show that there is little observed difference in public perception in taste
and odour between the most sophisticated modern plants (Belleville and Bayside) and the
simplest and older plants (Deseronto). From the field visits it is clear that Belleville
consistently delivers a first rate product which raises doubt as to how realistic public
expectations are; is the municipal supply being compared aesthetically with bottled
spring water? Given new standards for disinfection it would be difficult or impossible to
eliminate complaints about chlorine and chlorine was the complaint for a majority of
those surveyed.
It is evident that all plant operators in the study area take complaints seriously and act to
address them, however the primary concern is public safety and regulatory compliance.
As well, the lack of solid science regarding the actual source of taste and odour
compo)lnds and additional proven remedial measures makes it difficult to justify further
effort.
4.
TASTE AND ODOUR ISSUES IN THE GREAT LAKES
The choice of taste and odour as a criterion for impairment is unfortunate since no simple
definition is employed. A search of the literature confirms that standards are in place for
maximum concentrations of substances, some of which can be detected by taste or odour
at levels much below a~.cepted (health) limits. In many cases, equipment is installed as a
preventative measure, not because of a documented problem. In considering the
magnitude of this issue in the Bay of Quinte, it is necessary to look at the adjacent waters.
Throughout the water authorities drawing water from Lake Ontario and Lake Erie, taste
and odour problems are being encountered, often associated with zebra mussels. This
calls into question what is normal or typical in terms of treatment.
14
TM117510102F_050525
Bay of Quinte Drinking Water Taste and Odour Study
TECHNICAL MEMORANDUM
An example is the Erie County Water Authority (ECWA), which experienced a marked
increase in customer complaints beginning in 1993. It was determined that the cause was
elevated levels of MIB and geosmin in both raw and drinking water (ECWA, 1997).
Tests undertaken at ECWA labs linked the occurrence of these compounds to zebra
mussels.
The treatment method chosen was Powder Activated Charcoal (PAC) in combination
with mixed media filter beds. By employing this measure on an as-needed basis, taste and
odour problems have been remediated.
In Ontario, PAC or GAC are used in many water plants; Port Rowan adds the compound
in the summer months, the City of Toronto, the Region of Peel and the City of Hamilton
added PAC or GAC to the treatment process in 2000. Other plants have employed
potassium permanganate or ozone.
(
('
5.
CONCLUSIONS
1. From an examination of the survey data, taste and odour in the drinking water in the
Bay of Quinte remains an impaired beneficial use. There is no evidence that taste and
odour problems identified in the base year time frame (1989-1994) have since been
reduced.
2. Since a majority of the taste and odour problems are related to chlorine, it is difficult
to make any definitive conclusions on the reduction of taste and odour causing algae.
3. From an examination of water plant equipment and operations, there is no obvious
evidence of an lBU. The equipment in place in the plants visited is no more extensive
or elaborate than that elsewhere in the Great Lakes. Similarly operations such as the
addition of PAC are not unusual.
(.
4. The results of the survey suggest that the taste and odour problems are considered by
respondents to be a nuisance issue, not dissimilar to reports from other communities
bordering the Great Lakes. It was beyond the scope of the survey to look into the
question of whether the taste and odour present in the Bay of Quinte drinking water is
indicative of the presence of compounds harmful to health.
6.
RECOMMENDATIONS
Revisit the definition of IBU
Given the fact that taste and odour problems are common throughout the Great Lakes
region and that the cause is not necessarily nutrient loading alone, the Restoration
Council should revisit the'definition of lBU for this issue. While elevated nutrient levels
may be a direct cause of other lBUs, it is unclear that the levels now present in the Bay of
Quinte can be directly linked to the taste and odour complaints noted in the survey.
Participate in/stay abreast of taste and odour research
From the literature cited in this report it is clear that the taste and odour issue is common
to many operations beyond the Bay of Quinte and that the causes are not clearly known.
TM117510102F_o50525
15
Bay of Quinte Drinking Water Taste and Odour Study
TECHNICAL MEMORANDUM
Ongoing research and proposals for further work suggest that the Bay of Quinte region
could benefit from the results of this work and point the way for further improvements in
plant equipment and operations.
Encourage collaboration among Bay of Quinte Water Plant Operators
Operators in the region deal with a wide variety of equipment and practices yet share the
Bay of Quinte as a water source. Field visits indicate there is little opportunity for them to
share experiences and track new developments applicable to their situation. A series of
workshops would be a good vehicle for this purpose and could also help meet training
requirements.
7.
REFERENCES
Bay of Quinte RAP Coordinating Committee, 1993. "The Bay of Quinte Remedial Action
Plan Stage 2 Report - Time to Act"
Charlton, M.N, S. L'Italien, T. Howell, P. Bertram, M. Zarull, R. Thoma, and D. Culver,
2000. "Eutrophication or Undesirable Algae: Preliminary Beneficial Use Impairment
Assessment (Lake Erie). Technical Report 10, Lake Erie Lakewide Management Plan.
Erie County Water Authority, 1997. "Lake Erie Lakewide Management Plan". Technical
Report No.l1.
International Joint Commission, 2004a, "Restoring Beneficial Uses in Areas of
Concern ", as included in http://www.ijc.orglrellhoards/annex2Ibuis.htm#fishrest
International Joint Commission, 2004b, "Restoring Beneficial Uses in Areas of
Concern", as included in
http://www.ijc.orgirellboards/annex2/aoc phplbui area.php?aocid=2017&nation= CA
N
L'Italien, S. and L. Thorstenberg, 1998, Lake Erie LaMP Lake Erie Preliminary
Beneficial Use Assessment, Technical Report 11, Drinking Water Consumption
Restrictions or Taste and Odour Problem Restrictions.
Ministry of Environment, 1986. "Some Effects of Phosphorus Loading on Phytoplankton
in the Bay of Quinte, Lake Ontario"
Quinte Conservation, 2003. "Assessment of Impaired Beneficial Uses, IBU#9 Taste and
Odour of Drinking Water"
16
TM1175I0102F_050525
QUESTIONNAIRE PREPARED BY XCG CONSULTANTS LTD., MAY 2004 FOR BAY
OF QUINTE DRINKING WATER TASTE AND ODOUR PUBLIC SURVEY AND
REPORT
TELEPHONE SCRIPT:
Hello, my name is
. I'm helping conduct a survey of drinking water in the
Bay of Quinte area. The study is funded by the Ministry of the Environment and is part of the
Bay of Quinte Restoration Project. I'd like to ask you a couple of questions regarding the quality
of water you receive from the municipal water supply.
(:
** IF ASKED, GO TO PROJECT DESCRIPTION **
1. Have you lived at your present residence for the past 10 years or more?
2. Do you drink and cook with tap water?
3. Have you perceived objectionable taste or odour in the past or now? (If NO, go to 'Thank
You.')
4. If YES: Was this a problem in the past? (How many years ago?) _ _ . Is it still a
problem?
5. How would you describe the problem?
•
Chlorine?
•
Musty?
•
See detailed taste and odour description.
6. Is there anything else you could tell us about your municipal water supply?
THANK YOU. We appreciate your participating in our survey. If you would be interested in
the result, a copy of the summary report will be available at Lower Trent Conservation later this
fall.
PROJECT INFORMATION
Why are you asking about water supply problems? The taste and odour of drinking water had, in
the past, been reported as unpleasant in several of the Bay of Quinte municipalities. This often
occurred in the summer when algae was present. We are conducting the survey to see if water
quality in the Bay of Quinte has improved and the problem has been eliminated.
Is my water supply unsafe? Not at all. The tap water you drink is supplied by (example: The
City of Belleville) and is filtered and treated. A regular testing program is carried out and the
results are available to the public.
Who is the Bay of Quinte Restoration Council? When the Bay of Quinte was identified as an
area of concern in the 1990s (largely due to excessive weed and algae growth), a committee was
established to oversee remediation. This work is essentially complete and this study of ours is
one of the ones being conducted to see whether the earlier problems in the Bay of Quinte have
been remedied. The Bay of Quinte Restoration Council is headquartered in the Lower Trent
Conservation Authority. The results of our work will go to them (Barry Jones, Coordinator, 613394-3915).
For further information see, "Background, Terms of Reference, Bay of Quinte Drinking Water
Taste/Odour Survey"
Belleville Taste & Odour Survey Results
Name
Address
WS
Number
Near/Far
969-0110
N
968-6915
N
N/A
YIN
Years
TreatedlTap
5>
N
Taste or Odour
NowlThen
A-1 Limousine Service
38 Everett
O'Hara, V
252 Foster Av
Adams, C
26 Georgian Ct
968-5075
F
N/A
Boyle, J.P
144 Hastings Dr
962-8175
N
N/A
2-4-1 Pizza
379 North Front
967-0214
F
Y
10>
Zakos,T
62 John
966-1871
N
225 William
966-3495
N
Y
10>
A N A F Tartan Lounge
187 Front
968-9116
N
Y
50>
N
none ever
A&T Beauty Supply
292 Front
962-7702
N
Y
27>
N
N
Campbell, Doug & Linda
220 College East
967-4487
F
Cairns, Kim
3-215 Victoria
966-6010
N
Y
40>
N
none ever
Dixon, Langford
33 Fairway Ave
968-7873
N
Buffet Garden
365 North Front
967-7888
F
Y
1>
N
West Side Cafe
43 Dundas St West
966-0365
N
S.L Rodgers
Elgin St.
968-6777
N
Y
Ablett T
14 Taylor Crt
966-9594
F
Y
Abrahams D
191 Palmer Rd
967-6176
N
Y
Wilson, S
,
...
N
Y
treated
N
N
don't drink
N
Y very strong C odour, irritating to
skin, blue green colour.
5>
N
Y onloff sulfur type odour
3>
N
Y onloff sulfur type odour
Abrams Edward J
29 Cascade BI
962-4446
F
Y
16>
treated 6>
Abrams MA
5-C Prince of Whales Dr
976-8512
F
Y
6>
Treated
Acheson S
Cannifton
961-5091
F
Y
Acres K
165 George
968-8976
N
Y
3>
treated
Adams Arthur
75 Victoria Av
963-4370
F
Y
10>
bottled water
Y past experienced swampy algae
smell in summer and or strong
chlorine taste and odour, worsened
annually prompting treatment
to avoid chlorine taste and odour
filtered via Brita Y past bad taste, now gone
Y chlorine taste and odour
currently experience no smells or
odours
.
Belleville Taste & Odour Survey Results
Name
Address
Number
Near/Far
WS
YIN
Years
TreatecllTap
Taste or Odour
NowlThen
now and past putrid smell offlon also
chlorine at times
Adams Chas
72 Maple Dr
966-6426
F
Y
5>
treated
Adams Jos
44 Geddes
962-1401
F
Y
10>
bottled water
Adams N R
13 Cedar
966-7866
N
Y
17>
treated
bad taste in summer months always,
now chemical smells onloff
Adamson Earl
703-201 c Palmer Rd
968-3163
N
Y
17>
filtered
tastes like sewer
AddyG
50 Rollins Dr
968-2219
F
Y
5>
filter
Agapas C
15 Fairview
968-3317
Y
10>
N
N
Alexander A Ronald
61 Edgehill Rd
962-7940
F
Y
10>
bottled water
N
Alexander F P
15 Pine
968-8823
F
Y
15>
N
N
Alexander S
42 Victoria Av
962-1623
F
Y
10>
bottled water
N
Allan D
Cannifton Rd N
962-2348
F
Y
4
N
N
Allan FRoss
25 Woodland Acres
962-8219
F
Y
36>
bottled water
putrid smell and taste from algae in
past, now a strong chlorine odour
and taste
Baker William & Cindy
433 Foxboro-Stirling
969-1724
F
Y
12>
bottled water
chlorine smell and taste
4>
filtered
putrid swampy smell in summer
months years past, not this year
bad taste
Barkhouse D
21 Union
967-8156
F
Y
BarlowG&T
53 Prince of Whales Dr
962-8584
F
Y
7>
N
None
Barlow Robert & Molly
161 George
962-7608
N
Y
11>
N
bad taste unless refrigerated
Barlow Shane
208 Yeomans
968-7977
F
Y
<1
filtered
Barnes Robert
328 Foster Av
967-1679
N
Y
29>
N
putrid odour in past but not for
several years
Baron J R
24 Melrose Cr
962-0345
F
Y
<2
filtered
smells of dead fish and algae
BarratT J
28 Kensington Cr
968-7172
N
Y
30>
N
N never
74 Prince of Whales Dr
969-4440
F
Y
18>
N
N never
74-D Aikins Rd
967-8118
N
Y
2>
N
N
302-255 George
968-8470
N
Y
30>
N
Y periodically odourous in summer
Barre Wayne
Barrett C
Barrett C
Q
bad taste
musty odour and stagnant taste
Belleville Taste & Odour Survey Results
Name
Number
Address
NearlFar
WS
YIN
Years
TreatedlTap
Taste or Odour
NowlThen
Barriage D
33 Isabel
967·0774
V
7>
N
V chlorine
Barriage Rod
20 Pringle Dr
968·3529
V
3>
N
N
Barrie N
289 Albert
961·0977
V
3>
V
V,periodic brown discolouration,
stagnant taste (b&a filtering), metallic
taste
N
20 Boswell
969·1798
V
3>
V
V, ranges from extreme chlorine
taste and odour to brown
discolouration and stagnant muddy
odour
Bartle S
39 Dunnet Bl
961·7492
V
5>
V
N
Bartlett C
64 North Park Gdns
967·1364
V
66>
N
V always been odourous and foul
tasting
Bartlett K J
126 Hastings Dr
967·1380
Y
38>
N
N, never
358 Montrose Rd
962·6301
V
2>
N
N
334Dundas E
968·4198
V
8>
N
N
966·3437
V
40>
Barter Clinton
Barton K
,
Q
Barton S
Bashall SA
- -------------
~Donald
-
---- - - - - - - - - - - ~
.......
---
N
-------
N, but will not drink
Picton Taste & Odour Survey Results
Name
Address
Number
Near/Far
WS
YIN
Years
TreatedlTap
Noyes M
4 Ortona Cr
476-0289
F
Y
3>
N
O'Brian Roy
8 Talbot
476-0266
F
Y
4>
Y
Offord Donald
Allison Bruce
Anderson C
Ostrander G
Otterway Joe
Keep, D
Barrett Robert
Mitchel, John
Pannell W Bud
Parker L E
Barsley M
Bath H L
Beattie C&T
Pascoe H
Seeley DB
Payne Derek
Beaumont Donald
Beggs J R
Pettingill Y
Belisle DOUQ
Pliwischkies Herbert
53 York
33 Ontario St
28 LowSt
20 Ortona Cr
7 Bowery
54 York St
48 Paul St
20 LowSt
Downes Av
172 Picton Main
51 Union St
47 Ontario St
22 Paul St
8 Talbot
52-B Mary St
43 Paul St
9 Queen St
19 LowSt
133 West Mary
42 Washburn
374 Picton Main
476-9964
476-2496
471-1096
476--8185
476-6710
476-3529
476-3698
476-5448
476-5514
476-3324
476-8191
476-6451
476-5544
476-4608
476-3348
476-6467
476-2390
476-4577
476-6655
476-7153
476-3161
N
N
N
Y
Y
Y
Y
Y
Y
Y
Y
Y
Y
Y
Y
Y
Y
Y
Y
Y
Y
Y
Y
Y
6>
44>
1>
7>
30>
30>
5>
10>
40>
10>
25>
50>
10>
10>
10>
40>
20>
30>
12>
15>
35>
N
N
N
N
N
N
N
N
N
N
N
N
N
N
N
N
N
N
N
N
N
Mason, John
20 Spencer
476-3968
N
Y
16>
N
Bell R&B
BellWmA
Brown Terry
Poisson J
21 Picton Main
26 LowSt
25 Downes Av
349 Picton Main
476-8822
476-2467
476-5849
476-1622
N
N
N
N
Y
Y
Y
Y
9>
39>
4>
Summer
Y
N
N
N
Porter Cameron
3 Catherine
476-5904
N
Y
48>
Y culligan
_
,
F
N
F
N
N
N
N
N
N
N
F
N
F
N
N
N
N
F
Taste or Odour
NowlThen
N
constant swampy smell, periodically
chan Qed by stronQ chlorine smell
Chlorine
N
Chlorine
N
Chlorine
Chlorine
N
N
Chlorine
N
Chlorine
N
N
N
Chlorine
Chlorine
N
N
Chlorine
N
N
strong Chlorine, (very close to
treatment site)
sulohur smell, staanant taste
N
N
N
Y chlorine and discolourartion and
.
svv§lTlflY odours In (last
Picton Taste & Odour Survey Results
Name
Pringle Gerald
Address
118 West Mary St.
Number
476-2362
Near/Far
F
WS
YIN
Y
Years
65>
TreatedfTap
N
Taste or Odour
NowfThen
Y swampy T&O in summer and
chlorine
,
Deseronto Taste & Odour Survey Results
Name
Address
Number
Near/Far
WS
YIN
Years
TreatedITap
Y
Y
Y
y
y
20>
20>
1>
N
N
N
N
N
Y
<1
N
Taste or Odour
Nowrrhen
Allen B
Andress E
143 Main
444 Dundas
396-6922
396-5738
Asmar Hector Jose
Barker H L
BarroisH
Blakely John
91 Centre
138 Second St
143 First St
83 Green
396-6779
396-5985
396-5915
396-6044
258 Thomas St
396-5914
y
14>
N
247 Thomas St
396-5114
396-3481
396-2909
y
y
y
y
y
y
<1
N
N
discolouration in past (old pipes)
N
N
brown colour and swampy smell and
odour
N
23>
30>
N
N
N
chlorine
3>
4>
N
N
chlorine
N discolouration
2>
N
N
N
N
fish odour at times in summer
cloudy, bad taste
Boettcher Jim
Boisvert A
Bonner Lyle
,
Boomhour B
Boomhour M
77 Mill St
318 Maple St
257 Thomas St
Bowen R
BradshawW
Thomas St
164 Centre St
Brant Allen
Brant B
193 St George
315 Edmund
396-2397
396-3597
Brant L B
119 College St
Brant S
396-6038
396-6387
396-1838
7>
1>
1>
2>
48>
230 Thomas St
396-2931
396-2573
Y
Y
y
y
Bremmer David
177 Thomas St
396-3843
Brinklow Matt
Brown Peter
Browning E
420 Thomas
356 Main
52 Pearl
444 Thomas St
396-2405
Burridge Gary
Carr V&D
149 Main
Carter Joe
Cassidy Lance
193 Brant
61 Bryant
ChapmanT
Cherneski N & T
169MiIISt
391 Thomas
N
N
N
N
2>
N
y
18>
N
N
Y discolouration, bad taste & odorous
in past -- now good
396-3210
396-3022
396-3802
Y
Y
Y
Y
8>
4>
35>
N
N
N
chlorine
5>
N
N
396-6291
396-2969
Y
Y
<1
30>
N
N
N
N
Y smells like garbage
396-6556
Y
Y
3>
10>
N
N
Y
5>
N
396-3005
396-9945
N
N
N
Rust
Deseronto Taste & Odour Survey Results
Name
Address
Chumbley Morris F
Churchill P
221 Cross St
84 Centre St
Clark Brian
50-B Brant
Number
396-5124
396-2874
396-9909
---------- ----
Near/Far
----
WS
YIN
Years
TreatedlTap
Y
Y
Y
6>
9>
30>
N
N
N
Taste or Odour
NowlThen
chlorine
N
swampy/chlorine
Quinte West Taste & Odour Survey Results
Name
Papakiriazis Gregory
PeeverJ M
Petchiny G
Philbin M&C
Phillips A
Post Gwilym
Press R J
Radocasy James J
Rathburn Douglas
Reed D
Richter M
Riddle Steve
Ritter Richard
Robinson Kevin W
Rockey R
Rollins J
Russell Duane
Ryan Frederickson J
Ryan M C
Sagriff L
Sarty Brian W
Scharf Hugh
Short B J
Rutledge K
Sills Grant
Skinner Ken
Staalduinen Gary
Sob bart R J
Stewart Micheal
Story E
Number
NearlFar
WS
YIN
Years
TreatedITap
Colonial Rd
Moira W
252 Catalina Dr
339 Montrose Rd
A-152 Moira W
228 MoiraW
968-4429
969-7169
966-2526
967-8278
966-2049
962-1128
F
F
F
F
F
F
Y
Y
Y
Y
Y
Y
25>
3>
16>
5>
4>
30>
N
Y
Y
N
Y
Y
19LeeAv
962-8224
N
Y
40>
N
19 Moira W
101 Catalina Dr
439 Montrose Rd
234 Catalina Dr
505 Montrose
18 Moira W
190 Montrose Rd
4854 OldHwy2
6 Sandyhook Rd
50 Country Clb Dr
32 Old Stone Rd
18 Lee Av
119 Aikins Rd
19 Country Clb Dr
1628 OldHwy2
53 Colonia IRd
44 Burns Av
39 Country Clb Dr
85 Catalina Dr
112 Country Clb Dr
297 Colonia IRd
40 Catalina Dr
20 Sandyhook Rd
967-8346
966-3523
968-2841
966-4613
966-4929
966-6761
967-3872
967-2615
966-2589
962-4337
962-7506
966-0027
962-4502
967-6677
967-1920
968-7345
962-8438
966-7367
962-9801
968-9176
962-5663
962-6862
968-5115
F
F
F
F
F
F
F
N
N
F
F
N
Very N
F
N
F
N
F
F
F
F
F
N
Y
Y
Y
Y
Y
Y
Y
Y
Y
Y
Y
Y
Y
Y
Y
Y
Y
Y
Y
Y
Y
Y
Y
12>
24>
7>
18>
10>
<1
5>
2>
20>
30>
6>
5>
5>
2>
2>
10>
30>
26>
10>
10>
16>
34>
30>
N
N
N
N
N
Y
N
N
N
N
Y
N
N
N
N
N
N
Y
N
N
N
N
N
Address
,
Taste or Odour
NowlThen
Chlorine
Chlorine
N
N
N
Chlorine
Y 39 ago, smelled badly, none since
then
None other than rust
periodic chlorine
N
Y chlorine smell& odour in am
N
N
N
N
Chlorine in am
N
N
N
N
N
N
Chlorine
Chlorine
N
N
N
N
Chlorine
N