Corporation of the Town of Perth Drinking Water System 2019 Summary Report
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Corporation of the Town of Perth
Drinking Water System
2019 Summary ReportTable of Contents
DWS Summary Report Overview ..................................................................................... 4
DWS Information.............................................................................................................. 5
SECTION 1 – FAILURE TO MEET REQUIREMENTS ................................................... 6
1.1. Adverse Water Quality Incident reports (Drinking Water System) .......................... 6
1.1.1 AWQI # 144718 Total Coliform presence in distribution sample .............. 6
1.2. Ministry Orders ....................................................................................................... 6
1.2.1. Drinking Water System ............................................................................ 6
1.2.2. Water Treatment Subsystem ................................................................... 6
1.3. Notifications to MECP (MOECC) regarding operational issues .............................. 6
1.3.1. Private residence fuel spill into Tay River via Town storm sewer drainage6
1.3.2. Spill Notification 2456-BHLLZY - Settling tank sludge ............................. 7
1.4. MOECC Identified Known Failures to Meet Requirements ..................................... 7
1.4.1. Drinking Water System ............................................................................ 7
1.5. MOECC identified areas for possible improvement ................................................ 8
1.5.1. Drinking Water System ............................................................................ 8
1.5.2. Water Treatment Subsystem ................................................................... 9
1.6. Additional concerns meeting potential compliance or operational requirements .. 10
1.6.1. Drinking Water System .......................................................................... 10
1.6.2. Water Treatment Subsystem ................................................................. 10
1.6.3. Water Distribution Subsystem ................................................................ 11
SECTION 2 – SUMMARY OF PLANT FLOWS ............................................................ 12
2.1. Raw Water (Source water) ................................................................................... 12
2.2.1. Average Daily Service Water Flow: ........................................................ 14
2.2.2. Service Water Discharge: ...................................................................... 14
2.3. Plant process water .............................................................................................. 14
2.3.1. Waste Volumes ...................................................................................... 15
2.3.2. Geo tube membrane bag use ................................................................ 15
SECTION 3 – SUMMARY OF DRINKING WATER SYSTEM ABILITIES .................... 17
3.1. Water Treatment Ability ........................................................................................ 173.1.1. Disinfection ability .................................................................................. 17
3.1.2. Chlorine Dioxide use .............................................................................. 17
3.1.3. Coagulation abilities ............................................................................... 18
3.1.4. Flocculation and sedimentation abilities ................................................. 19
3.1.5. pH adjustment (use of lime) ................................................................... 19
3.1.6. Fluoridation abilities ............................................................................... 20
3.1.7. Pumping capacity................................................................................... 20
3.1.8. Process Wastewater Residue Management ability ................................ 22
3.1.9. Computer System .................................................................................. 23
3.2. Water Taking Ability.............................................................................................. 23
3.3. Water Storage Ability ............................................................................................ 24
3.4. Water Treatment and Distribution Personnel ........................................................ 25
4.1 Appendix Table 1 – Summary of Flows January 1, 2019 to December 31, 2019 . 26
4.2 Appendix Table 2 – Historical Average Daily Treated Water Flow (m³) ................ 27
4.3 Appendix Table 3 - 2019 Raw Water Taking ........................................................ 28
4.4 Appendix: MOECC 2018 Inspection Report Non-compliance issues and
Recommendations ......................................................................................................... 292019 DWS Summary Report
DWS Summary Report Overview
A Summary Report, as per Ontario Regulation 170/03, Schedule 22 must be prepared for
each drinking water system in the province of Ontario. The report must be provided no
later than March 31 to members of Municipal Council.
The DWS Summary report will cover a period for the preceding calendar year, January 01
to December 31, 2019.
The completion and presentation of this report will also fulfill the requirement for a
compliance report to be produced in accordance applicable regulations.
Section 1 contains,
any failures during the reporting periods to achieve the requirements of the Safe
Drinking Water Act, associated drinking water regulations and guidelines, any
approvals, any operating licences or permits, or any orders applicable to the Perth
DWS system;
duration of the failure, and measures taken to correct the failure;
any priority concerns that might lead to failures to meet the operating requirements.
Section 2 contains,
summary of quantities and flow rates of water taken from the Tay River, in addition to
water production and process wastewater generation.
Section 3 contains,
an overview summary of the DWS water treatment abilities
summary of the DWS water taking ability, DWS water storage ability,
summary of DWS operating personnel
Supplemental Perth DWS information sources would include, but not limited to,
The Town of Perth Water Treatment Plant year end documentation,
The Town of Perth Water Distribution year end documentation,
The Town of Perth DWS Annual Report.
Supplemental government legislation sources would include, but limited to,
Safe Drinking Water Act, 2002
Ontario Regulation 170/03, Drinking Water Systems
Ontario Regulation 169/03, Ontario Drinking Water Quality Standards
Ontario Regulation 128/04, Certification of Drinking Water System Operators and Water
Quality Analysts
It is noted to ensure currency, up to date documents can be reviewed at http://www.e-laws.gov.on.ca.
Supplemental government support documentation is available at the Ministry of the Environment
and Climate Change’s Drinking Water Ontario website, https://www.ontario.ca/page/drinking-water.
Perth Drinking Water System Summary Report 2019 Page 4DWS Information
Drinking-Water System Number 220001272
Drinking-Water System Name: Perth Drinking Water System
Drinking-Water System Owner: Perth, The Corporation of the Town of
Period being reported: Jan 01, 2019 to Dec 31, 2019
Latest MOECC Inspection Nov 20, 2019
Previous MOECC Inspection Nov 21 and 23, 2018
Drinking-Water System Category: Large Municipal Residential System (LMRS)
Class III Water Treatment Subsystem,
Drinking Water System Facilities
Class I Water Distribution Subsystem
Municipal Drinking Water Licence (MDWL) 160-101
Licence Issue Date August 04, 2016
Licence Revision Date (most recent) August 02, 2017 (Schedule A revision)
Licence Expiry Date August 03, 2021
Drinking Water Works Permit 160-201
DWWP Issue Date August 04, 2016
DWWP Expiry Date August 03, 2021
Permits to Take Water 7770-A8HKRH
PTTW Issue Date March 29, 2016
PTTW Expiry Date March 31, 2026
Water Taking Location Tay River
Financial Plan Number (under O. Reg. 453/07) 160-301
Accredited Operating Authority The Corporation of the Town of Perth
Operating Authority No. 160-OA1
Operational Plan No. 160-401
Perth Drinking Water System Summary Report 2019 Page 5SECTION 1 – FAILURE TO MEET REQUIREMENTS
1.1. Adverse Water Quality Incident reports (Drinking Water System)
1.1.1 AWQI # 144718 Total Coliform presence in distribution sample
Notification from the lab was received on February 05, 2019, that a distribution sample
from 1881 Rogers Road (taken Feb 04) was tested to have a Total Coliform count of 3.
Proper subsequent notifications were made to authorities, and corrective action of
resampling at the site was undertaken. The resampling tests came back with 0 Total
Coliform, and notice of issue resolution submitted on February 07, 2020.
1.2. Ministry Orders
1.2.1. Drinking Water System
No MOE orders issued.
1.2.2. Water Treatment Subsystem
No MOE orders issued.
1.2.3. Water Distribution Subsystem
No MOE orders issued.
1.3. Notifications to MECP (MOECC) regarding operational issues
1.3.1. Private residence fuel spill into Tay River via Town storm sewer drainage
On March 29, 2019, MECP Spills Action Center contacted Town staff regarding a
chemical spill reported in the Tay River (downstream of the WTP). Town staff and the fire
department worked to contain the spill at the Peter St bridge, and to investigate a possible
source of the spill. WTP staff conducted their investigation and found the source to be
downstream of their facility’s water intake, and not associated to their operational
activities.
On March 30, 2019 the source was determined to be a leaking fuel tank form a transport
truck parked in a residential area. The fuel spill was entering an adjacent Town storm
sewer, and discharging out to the Tay River. The discharges would fluctuate with the on-
going overnight rainfall. The truck fuel spill was contained by Town staff and site
mediation measures started by the trucking firm’s contracted services.
Although the notifications to MECP, MOH, and downstream users was not due to a result
of DWS operational issues, it is mentioned as significant Town resources was attributed to
this situation.
It is also noted that on April 05, 2019, another small fuel spill was reported on the small
Tay River involving MECP notifications. It is suspected this subsequent spill was related
Perth Drinking Water System Summary Report 2019 Page 6to the March 29 spill, where a pocket of fuel was lodged in a downstream storm sewer,
only to be released after increased water flow in the adjacent stormwater catchment area.
(probably hydrant flushing more so than rainfall).
1.3.2. Spill Notification 2456-BHLLZY - Settling tank sludge
On November 03, during a Sunday WTP site visit, process wastewater sludge was noted
on the grounds outside settling tank 1. The spill material was contained, and absorbent
placed down. Within a short time, the spill leakage had ceased. The estimated amount of
the spill was 50 L. The reason for the suspected leakage will be further investigated in the
spring of 2020 when the ground thaws and tank can be drained again for inspection.
1.4. MOECC Identified Known Failures to Meet Requirements
An MECP DWS inspection was conducted Nov 21 and Nov 23, 2018, with the Inspector’s
report released March 14, 2019. Required action items are listed below in sections 1.3.1
to 1.3.3.
1.4.1. Drinking Water System
Requirement failure Requirement location Duration of failure Any corrective action taken
Not ensuring all Schedule A and Required action(s) to Indication that a written action
equipment was Schedule C of the be implemented plan for monthly BET sampling
installed with BET DWWP indicate once full BET testing was forwarded to MECP.
system measures to be and commissioning
implementation implemented as to is completed. Indication of an O/M manual
ensure proper operations for BET operations was
forwarded to MECP.
1.4.2. Water Treatment Subsystem
Requirement failure Requirement location Duration of failure Any corrective action taken
Exceedance of LLP Multiple (2) LLP’s were For ~4.33 hrs to WTP staff took all
flow of 106 L/s needed to keep up with maintain sufficient appropriate corrective
water demand due to a water supply measures at the time and
watermain break located matching outgoing made proper notifications.
on service line feeding treated water flow
back into the WTP. until watermain No further actions were
break was isolated listed in the inspection report
Perth Drinking Water System Summary Report 2019 Page 7Failure to report a MECP inspection Feed disruption of ~ Written procedure was
coagulant feed indicate that any 1 hour (where some developed implementing the
interruption interruption of the feed did occur but at MECP inspector’s findings.
coagulant feed is a reduced rate).
contrary to the Coagulant feed alarms were
Disinfection procedure, Sensors were still reviewed and updated where
and reportable under sensing some flow, possible.
Section 16-4 so alarms did not
occur immediately Different style of chemical
metering pump is being tested
and implemented.
1.4.3. Water Distribution Subsystem
Requirement failure Requirement location Duration of failure Any corrective action taken
Insufficient daily MECP inspector No specific date or MECP recommendation(s) that
operations log entries indicated no comments time, just a general “ operators enter comments/
or details were entered in observation over the details in the Daily Operations
the logs regarding inspection period. Log for the daily activities/
operations performed operations performed in the
during the operating shift. The inspector was water distribution system
informed that no during the operating shift. It is
entries were done also recommended that
since no equipment operators document the
was taken out of communication between the
service, or no OIT and the WDS OIC and/or
abnormal operations ORO.”
occurred.
1.5. MOECC identified areas for possible improvement
An MECP DWS inspection was conducted Nov 21 and Nov 23, 2018, with the Inspector’s
report released March 14, 2019. The Report contained some recommendations and best
practice issues identified during the inspection period, to which owners and operators can
develop an awareness of and consider measures to address them, all in the interest of
continuous improvement.
1.5.1. Drinking Water System
Any corrective
Issue noted Recommendation Status
action taken
No Bylaw for The Town consider developing and As mentioned
Water Usage implementing a Bylaw and/or policy for Water also in 2017
Usage, and that the Town consider inspection
conducting a water use and loss audit. report
Incorporating any That the Town develop an action plan to Staff working Asking project
alterations into ensure the alterations are incorporated into on updating contractors provide
subsystem process flow diagrams, process and when possible. updated drawing or
diagrams and instrumentation diagrams and record diagrams at time of
drawings drawings and diagrams within one (1) year of process
the substantial completion of the alterations. implementation.
Perth Drinking Water System Summary Report 2019 Page 81.5.2. Water Treatment Subsystem
Any corrective
Issue noted Recommendation Status
action taken
Single phone line for That the Town maintain a dedicated Mentioned in In 2019/20, SCADA
multiple alarm phone line to support the WIN911 past report comm lines system
notification systems communication system; that a separate was upgraded to
backup system for the autodialer system follow and surpass
is provided, and that the autodialer is MECP suggestions,
connected to a dedicated phone line to through backup
ensure a fully functioning and secure off- programs and
site alarm notification system. digital line installs.
Use SCADA data That the WTP Operators consider using Mentioned in On-going measures
more to record min’s the data from the SCADA Daily Reports to past report, as done to include
and max’s for better provide the information required by a method of SCADA report data
assess compliance, Section 12(1) of O. Reg. 170/03; and that improving data into monthly reports
and reflect multiple WTP operators review the SCADA interpretation and use as an
low/high events Monthly Reports on a regular basis. auditing tool when
review of data
A fixed pH value of That the Town proceed with connecting Mentioned in TW pH is being
7.5 is used in the CT the online continuous pH meter to the past report. monitored by
calculations SCADA system for the treated water to SCADA, and using
allow the actual (real-time) pH values to The use of 7.5 as part of CT
be used in the SCADA CT calculations. pH reflects the calculations is
higher limit of being considered.
typical ranges
No reservoir That the reservoir be inspected to confirm Construction ODS Marine divers
inspection after the integrity of the reservoir's walls to was on-going inspected the tank
Phase II construction ensure proper disinfection is being until late 2018 walls early in 2019,
provided. once conditions
and scheduling
allowed
Improper planned To follow WTP staff concerns that the Final install of Better location was
location of BET dechlorination system is placed above the the system identified through
dechlorination feed chlorine contact chamber as indicated in was not done staff involvement
system the engineer’s construction plans at inspection
1.5.3. Water Distribution Subsystem
Any corrective
Issue noted Recommendation Status
action taken
Lead testing in Tay That Lead testing is performed within the Mentioned in Sampling site done
Valley distribution system components located in past report in 2019, and a
(DWS services) Tay Valley Township during the next TWP site to be
round of lead sampling. done annually now.
Security issues at the The equipment room located at the base Mentioned in Brought to
water tower of the water tower to be equipped with an past report management‘s
intrusion alarm; and that the water tower attention for
is provided with security lighting. consideration
Perth Drinking Water System Summary Report 2019 Page 91.6. Additional concerns meeting potential compliance or operational requirements
As apart of asset management efforts, significant issues or areas of concern that might be
viewed as potential impact items to operations are listed. These lists contain issues
identified by operational staff and management which might,
pose potential risk with inability to meet compliance and/or operational
requirements,
help prevent equipment failure or down time,
assist with more efficient operations.
Please also refer to Section 3,
1.6.1. Drinking Water System
Issue Concern Corrective action taken or proposed
Relevant water computer programs Made progress working with Town’s IT
industry computer updating needed contractor in 2019 to upgrade CPU’s and
programs some of the operating programs
1.6.2. Water Treatment Subsystem
Issue Concern Corrective action taken or proposed
Process residue Concern for lack of Investment in heat trace cables for some
management ops cold temperature outside water lines in 2018, however inside
operations bag capacity concerns continue with few
contingency plans possible contingency options currently
Reservoir isolation Equipment is aged Reservoir valve replacement program initiated
valves and unreliable in 2017, delayed in 2018, revisited in 2019,
and need in 2020 to continue with priority
valves whenever feasible
Dry Chemical Equipment is With increased unmanned facility operations,
volumetric feeders becoming aged and concern is heighted. Staff have implemented
of concern some remedial actions; however, equipment
style is now outdated, and liquid chemical
options are being considered.
Auxiliary power On-site portable A permanent generator installation is planned
generation generator issues in for 2020
2019
Bulk chemical Proximity of the Investigation into options continue.
storage bulk chemical
storage tanks
Building Concern with An engineering study to be done to divert
wastewater amount of “clean “clean wastewater “away from process
generation water” being residue treatment (ie roof drains, coolant
treated water, analyzer sample water, work sinks)
Perth Drinking Water System Summary Report 2019 Page 10Building Some outstanding Condition of roof persists.
infrastructure items identified in Some concerns exist from designated
past reports still substances report.
Facility Security Security fencing Discussed at MECP inspections previously.
and cameras
installed to monitor Growing operational infrastructure outside the
building exterior building now exists – need for measures with
areas process residue infrastructure and reservoir
Continue Predictive maint Predictive Maintenance allows the ability to
developing a monitoring is more recognize the onset of degradation before
predictive important with less significant deterioration occurs.
maintenance manned facility
program approach hours.
Larger volume Both have become Preliminary investigations into use of
Flowmeters aged; need to magnetic meter technology to replace existing
(Raw water, consider newer venturi and orifice plate use
Discharge water) equipment
Operational Continual Removal of 600V heating systems and
electrical demand assessing of replacement with smaller voltage heaters
electrical needs for occurred in 2019.
upgrading or unit
replacement Replacement of old 600 V heating contactor
panel, with new breaker panel, replacement
of heating wiring to filter gallery in 2019.
High voltage pump New MCC ability to To use existing MCC technology, and
motor monitoring monitor pump incorporate other monitoring equipment to
operations not fully help establish a predictive maintenance
utilized approach for aging pump motors
Further Basic automation The focus of automation needs to continue
automation operational needs addressing more in-depth treatment process
installations and are in place monitoring to allow SCADA to perform a more
upgrading (on/off), but more efficient operations and water quality issue
digital upgrades are alerting.
required to move
forward. Replacing outdated analog circuitry needs to
continue, as a significant majority of the work
remains.
1.6.3. Water Distribution Subsystem
Issue Concern Corrective action taken or proposed
Elevated tank 10” Is faulty and needs Identified in the 2019 Infrastructure Review,
fill valve to be replaced and brought to Management’s attention
Lack of recent With new road While it is realized that perhaps road work is
road and work, upgrades to not a high priority every year, the issue has
infrastructure work aged distribution been brought to Management’s attention for
system areas might consideration during budgetary discussions.
happen
Perth Drinking Water System Summary Report 2019 Page 11SECTION 2 – SUMMARY OF PLANT FLOWS
2.1. Raw Water (Source water)
Table RW-3 located in the reports Appendix offers an individual daily RW flow expressed
in Liters/day (1000 L = 1 m3).
The table below (RW-1) gives the monthly average RW flow, monthly single day max and
min flows, and the monthly total RW intake flow volume. A comparison of the single day
maximum of the month to the PTTW allowable volume of 9092 m3 is shown.
Table RW-1
2019 Raw Water Volumes
Average Minimum Maximum TOTAL FLOW Daily Maximum % of
Daily Flow Daily Flow Daily Flow PTTW Allowable
(m3)
(m3) (m3) (m3) Volume
January 3071.6 2747 3804 95,220 41.8%
February 3121.6 2479 3492 87,404 38.4%
March 3138.1 2725 3472 97,281 38.2%
April 3057.9 2478 5322 91,737 58.5%
May 3056.7 2569 4351 94,759 47.9%
June 3082.8 2523 4006 92,483 44.1%
July 3472.9 2790 4323 107660 47.6%
August 3259.5 2634 4028 101,043 44.3%
September 2884.7 2297 3308 86,540 36.4%
October 2980.0 2135 4896 92,380 53.8%
November 2795.4 2332 3404 83,861 37.4%
December 2830.9 2483 3507 87,759 38.6%
ANNUAL TOTALS avg 3062.68 Min 2135 Max 5322 Total 1,118,127
2.1.1. Average Daily Raw Water Flow:
The monthly average of daily average raw water flow was 3062.68 m³ in 2019, or
approximately 33.69% of the PTTW.
The daily average in 2017 was 2084 m³, followed by 3170 m3 in 2018. Factoring weather
conditions, a continued consistent water demand over recent years can be shown.
Perth Drinking Water System Summary Report 2019 Page 122.1.2 Maximum Raw Water Flow:
The maximum raw water flow days in 2019 occurred during Town hydrant flushing times,
with the highest being 5322 m³ (April 30), and the second highest 4896 m³ (October 08).
Spring flushing (April 29-May 02) had an average day flow of 4492.0 m³
Fall flushing (October 07-11) had an average day flow of 4350.5 m³
This is relevant as the PTTW maximum of 9090 m3 can be exceeded during water
distribution maintenance work times.
High volume times were noted during July 9-11 days (July 10 with 4323 m³, with an
average of 4022.3 m³ over the three days). A second higher volume time was noted over
August 20-21 (averaging 3867.0 m³/day). Both these times are reflective of use during
hot dry climate times, but still under 50% of the PTTW allowable volume for normal
operations) .
2.2. Service Water (Treated Discharged Water)
Below are the Treated Water monthly volumes, noting the high daily flow volume in April
and October can be attributed to Hydrant Flushing week(s). Water main breaks can also
be associated with high treated water flows.
Table TW-1
2019 Treated Water Volumes Discharged to Town
Average Minimum Maximum TOTAL FLOW
Daily Flow Daily Flow Daily Flow
(m3) (m3) (m3)
(m3)
January 2972.0 2649 3283 92,132
February 3035.9 2734 3342 85,005
March 3046.6 2722 3409 94,444
April 3037.7 2453 5119 91,131
May 3049.2 2612 4407 94,525
June 3062.4 2592 3535 91,871
July 3468.7 2864 4101 107,530
August 3228.3 2552 3849 100,076
September 2902.3 2534 3276 87,070
October 2912.4 2449 5068 90,284
November 2707.3 2422 2927 81,220
December 2710.6 2315 3079 84,028
ANNUAL TOTALS avg 3011.11 Min 2315 Max 5119 Total 1,099,316
Perth Drinking Water System Summary Report 2019 Page 132.2.1. Average Daily Service Water Flow: The daily average service water flow was 3011 m³ in 2019. This volume was comparable to 2018 (3072 m³) and 2015 (3057 m3). Lower averages flows were experienced in 2017 (2653 m³), and 2016 (2657 m³). Over 5 years (2015-2019), the average daily service water flow was 2890 m³. 2.2.2. Service Water Discharge: In 2019 a total of 1,099,316 m3 was discharged to the Town. This was comparable to previous years, 2018 (1,122,056 m3), and 2015 (1,115,473 m3). Lower annual total volumes were realized in 2017 (967,217 m³), and 2016 (972,383 m3). Over 5 years (2015-2019), the average annual water discharged was 1,055,289 m³. This volume is relevant to doing future financial projections of water service revenues. 2.3. Plant process water The WTP Process Wastewater Residue Management now involves Backwash Equalization Tank (BET) use, in conjunction with Geo Bag system deployment. Sludge from the settling tanks is typically directly to the Geo Bag treatment process, whereas backwash wastewater is sent to the BET(s) to allow sludge separation and supernatant removal. The BET sludge is then directed to the Geo Bag system for treatment. One significant change to process residue operations needed to happen in June 2019, when the WTP facility was no longer manned during weekend hours. Given the small Geo Bag sludge hopper size, diverting weekend settling tank sludge removal volumes to the BET(s) for storage would be required. That settling tank sludge is then transferred back to the Geo Bag hopper whenever other batching process is occurring. The weekend BET (settling tank) sludge is more dense than normal settling tank sludge, given compaction and supernatant removal can occur. The Geo Bag system is operated manually by operators during normal working days. Although designed to be an automated process, it was found to be unreliable which concerns raised as to operating it without staff readily available on-site. BET operations were done in 2019 with manual operations by operators requiring to be on-site with vigilant monitoring. The installed equipment would not allow for proper automated operations to occur. A different type of tank level sensors (radar) will be under trial in 2020, and hopefully prove more reliable than the ultra-sonic sensors currently in place. The settling tank sludge removal system (chains and flights) are becoming aged and soon in need for replacement consideration. During 2020 settling tank cleaning, a structural inspection of tank 1 needs to occur considering the suspected sludge seepage found outside it’s eastern wall in 2019 prior to ground freeze up. Perth Drinking Water System Summary Report 2019 Page 14
Settling tank cleaning occurred twice in 2019 (spring and fall), utilizing the WTP process residue management processes instead of transporting the sludge off-site for direct disposal at the WWT facility (lagoons). The accumulation of “clean wastewater” from non-process water sources (such as roof drains, work sinks, analyzer bypass flows, engine and pump coolant water) continues to fill BET(s) and use up residue processing time and resources. As mentioned in the 2019 DWS Summary Report, a feasibility study should be considered to explore options to divert this water away from the process residue management system and possibly to sanitary sewer discharges. 2.3.1. Waste Volumes In 2019, a total volume of 13,528 m3 was directed to the Geo-tubes (Solids collection membrane bags). As suspected, this was down from 2018 (14,250 m3) when BET commissioning did occur; and more reflective of 2017 (13,572 m3). However, the volume being generated annually can be influenced by many uncontrollable operational factors, such as raw water conditions and rainfall accumulation (overabundance or lack of). Backwash wastewater generation for 2019 was estimated at 10,934 m3. This was comparable to past years (2018 at 11,391 m3; 2017 in 9,155 m3). Air scouring has contributed to less backwash water generation (2016 estimates of 14131 m3). Backwash optimization efforts (slightly higher flow rates for less time) has helped with filter run efficiencies. 2.3.2. Geo tube membrane bag use To start 2019, the greenhouse bag had started taking the bulk of the waste stream and had 1,063 m3 directed to it, or ~12 % full capacity. Bag 2 (outer) had been undergoing dewatering late in 2018 (around 8,500 m3 to it, or 100 % capacity), and froze up to start 2019 (out of service). Bag 1 (outer) was being used whenever possible but was not frequently (~3,046 m3 to it, or ~36% capacity). Operations were in a similar situation as they were to start in 2018. On February 04, the greenhouse bag suffered a tear which made use of it no longer possible (only 2,379 m3 been sent to it)…(in 2018, Bag 3 was used into April). With bag 2 and 3 out of commission, Bag 1 was the only remaining option, with plenty of freezing operational difficulties to be overcome. The issue with Bag 3 was it was once again ordered a bit larger to try and gain extra room (69’ (2018); 66’ (2017); 72’ (2016), and unfortunately the bag got snagged on wall debris as it was starting to inflate. The smaller size bag was ordered for 2019 winter start, and end walls were padded with insulation boards. Perth Drinking Water System Summary Report 2019 Page 15
On May 08, Bag 2 was removed and the 8487 m3 of geo wastewater equated to 257.63 metric tonnes of debris to the landfill. A replacement bag was deployed on May 31, same length but slightly larger circumference and different filling port locations. Bag 1 was taken out of service June 04 with 7390 m3 of geo wastewater directed to it. The smaller volume was reflective of the difficulties and stress it received during the freezing operating condition earlier in the year. It was removed Oct 24, with a landfill disposal weight was 208.60 metric tonnes. A new bag was deployed December 10. After dewatering and drying, the greenhouse bag was removed on July 18, with the 2379 m3 of geo wastewater equating to 47.83 metric tonnes of solids to landfill. A new greenhouse bag was deployed on November 13 as a relief when both outer bags and lines unexpectedly froze up. Bag capacities assumptions are very difficult and only based on previous years’ volumes sent to the bags, as several factors significantly impact bag performance (sludge density, bag dewatering ability, bag conditioning, bag durability). Using 8500 m3 as a bag capacity reference number, at the end of 2019 outside bag 1 was at ~5% full capacity, and outside bag 2 close at 74% capacity. If ~6500 m3 capacity was assumed for the 2019 deployed greenhouse bag, it was ~ 16% full capacity. Perth Drinking Water System Summary Report 2019 Page 16
SECTION 3 – SUMMARY OF DRINKING WATER SYSTEM ABILITIES
3.1. Water Treatment Ability
The Perth water treatment plant continues to maintain a strong position in supporting its
ability to provide a reliable supply of safe, clean drinking water to its community. Funding
reserves are maintained in case of an operational emergency or unexpected major
breakdown.
3.1.1. Disinfection ability
Disinfection of the drinking water is ultimately achieved through two points of application –
primary disinfection – dosed as water enters the clear well; and secondary disinfection –
dosed at the treated water discharge point. Both critical treatment processes have
redundancy in the pumps as well as the dosage lines.
Varying raw water conditions require operators to adjust and control chemical dosages to
meet regulations in a cost-effective manner.
It should be noted that many factors contribute to the overall disinfection process,
including pre-treatment, coagulation and pH control. Of most importance is the daily CT
calculation. The CT value is the product of the concentration of a disinfectant and the
contact time with the water being disinfected. WTP operations in 2019 continued to
exceed the legislated CT operational requirements, supporting the ability to meet proper
disinfection needs.
Another critical factor for proper disinfection is turbidity. Water with high turbidity can
impede the disinfection process, and why disinfection occurs after filtration. The objective
is to maintain filter effluent turbidity of < 0.300 NTU for 95% of the time. The Perth WTP
exceeded the 0.300 target on each filter for minimal time over the entire year, 32 minutes
in total for filter #1, and 27 minutes in total for filter #2. A typical daily average of 0.03 to
0.04 NTU is being realized. Putting this in perspective, the reportable level for filtrate
water is 1 NTU after 15 minutes, whereas at 5 NTU water can be visibly cloudy, and
murky water found around 25 NTU.
Considerations with disinfection abilities might be,
a need to investigate primary disinfection chemical metering equipment
alternatives, and while the existing is currently reliable, it is becoming more cost
prohibitive when replacing parts,
a need to explore disinfection sampling pump options, and
to prepare for early GAC replacement (filtration media) due to air scour operations.
3.1.2. Chlorine Dioxide use
Chlorine dioxide continues to be generated seasonally on site and plays an important role
in achieving disinfection while mitigating the formation of chlorine disinfection by-products
Perth Drinking Water System Summary Report 2019 Page 17such as THM’s and HAA’s. These disinfection by-products are suspected carcinogens and
are commonly formed when high doses of chlorine gas or sodium hypochlorite react with
raw water heavily laden with organic matter. Chlorine dioxide use is uncommon among
water treatment facilities due to chemical cost however the advantage of a “cleaner”
disinfection process with less by-product formation is worth the extra cost during extreme
seasonal water quality challenges seen in Perth.
As well, the renewal of the municipal Drinking Water License saw the additional sampling
requirement of Chlorates and Chlorites added as a quarterly sampling requirement. The
availability of an accredited laboratory to perform the tests is limited, and in-house lab
sample preparation has become even more difficult with short delivery time restrictions.
Considerations with continued Chlorine Dioxide use
The Chlorine dioxide system was only exercised in 2019 as apart of an emergency
planning exercise (~302 m3 RW treated).
In 2018, it was only used to treat under 20,000 m3, or less than 1.5% of the time.
With the less chlorine dioxide use, stock chemical stock concentrations are
degrading in their containers, so more concentrate is needed to create the same
amount of chlorine dioxide, and possibly higher by-product creation risk.
3.1.3. Coagulation abilities
The water treatment plant employs a premium coagulant called PAX XL-6 to aid in the
flocculation and sedimentation of suspended solids in water prior to filtration. Although
more expensive than conventional coagulants such as aluminum sulphate, product usage
is reduced, and it outperforms other less expensive chemicals at certain critical
temperature ranges. Winter months and the associated cold-water temperature and
density present the most difficult conditions for the coagulant to settle the solids. Our new
licence allows for pH enhancement (use of HCl) in situations of high pH or alkalinity raw
water conditions that make floc formation difficult.
Tube replacement costs associated with maintaining peristaltic pumps for coagulation
operations are becoming significant, due to higher line back pressure and excessive tube
wear. The existing peristaltic coagulant pumps could be used in better suited application.
In 2019, a new motor driven diaphragm pump was purchased to try as a coagulant pump,
and while attachments could better efficiency, initial trials have been promising. it could
require Annual tube replacement costs for coagulation use can easily extend above 15%
of a different style pump, making a multi year replacement plan more attractive.
Consideration with current coagulation setup might be,
to investigate more cost-effective alternatives, and/or seasonal product alternating
options,
to continue the switch to the motor driven diaphragm metering pumps, along with
back pressure creation devices and flow dampeners
Perth Drinking Water System Summary Report 2019 Page 18 the existing flash mixer is adequate for current operations, it is becoming aged and
consideration of an in-line static mixer needs to factor into any future RW header
planning.
Consider feed line alternatives
3.1.4. Flocculation and sedimentation abilities
The flocculation equipment is becoming aged and in need of frequent repairs. Drive shaft
bearing replacement efforts continued in 2019. Parts of the flocculation were discovered
to have metal fatigue due to rust and corrosion. Cracking along the floc tank walls has
been noted and in need of inspection by qualified personnel.
In November 2019, settling tank sludge was noted outside Tank 1, which needs to be
investigated further in 2020 once the ground thaws and better suited tank entry times
exist. Repair work to a older cracked wall situation (~ 2002) might need revisiting.
There are aged water supply lines in the settling tanks that are coming loose from the wall
and in need of removal or replacement.
Sludge removal equipment in the sedimentation (settling) tanks has been continually
repaired over the past years, mainly the PPE thermoplastic chain links becoming fatigued
and worn. Cost assessment was undertaken in 2019, and while stainless steel is an
option, replacement with PPE thermoplastic would be more cost efficient and provide less
stress on the existing infrastructure (supports, drive shafts, motors).
Considerations with Floc and Sedimentation processes might be,
Investigation of settling tank 1 wall, and assessment of water lines in tank
Continue with an inspection and preventative maintenance program for floc drives
using outside machinist contractors
Allow time for proper flocculation repair work during 2020 tank cleaning
Implement a sludge removal chain replacement plan
3.1.5. pH adjustment (use of lime)
Following the coagulation and disinfection processes, where the pH of the water is
lowered through the addition of chemicals, hydrated lime needs to be mixed in the
clearwell to return the pH to a range of 7.1 to 7.3. This range is desired to ensure the
water within the distribution system is close to neutral and thereby not aggressive in the
deterioration of the distribution network as well as homeowner plumbing and fixtures.
In 2019, preliminary investigations in using liquid pH adjustment chemical was initiated,
and should be allowed to continue in 2020.
Perth Drinking Water System Summary Report 2019 Page 193.1.6. Fluoridation abilities Granular fluoride is added in the same application area as the lime. As the volumetric feeder is aged, a continual feed is not possible due to the low dosage requirements. As a result, a “feed and starve” approach is required to keep residual levels in the targeted and compliant range. Based on grab sampling, this operational approach has appeared effective enough. In 2019, the continuous monitoring fluoride analyzer did indicate some fluctuations but not as significant as initiated thought. Considerations with future fluoridation practices might be, Include liquid chemical dosing into any future planning, Implement a 5-year reassessment program for continued fluoride use. 3.1.7. Pumping capacity The existing pumping capacity meets the needs of the facility and the water demand from the drinking water system. The HLPs adequately operate with the SCADA to supply the Town’s distribution system and maintain sufficient water pressures. The LLPs operate sufficiently to move enough water through the facility to meet the demands while maintaining process design requirements. LLP (low lift pumps, raw water supply) In 2018, flows on the smaller capacity LLP’s have dropped off slightly. Troubleshooting the issue started in 2018 and carried on through 2019. The 2019 focus was on the electrical components, using specialized technical support to run various amperage and load tests on the motors and the new wiring connections to the new MCC. All indications appeared the primary source was not electrical, and possibly mechanical somehow. The electrical investigations did however indicate some motor fatigue on the smaller LLP’s. It was identified that perhaps a spare 10 HP motor should be on hand. A new motor would be more efficient than the older existing ones, and having one readily available would address the 8-10 weeks’ delivery time when a motor is urgently needed. In January 2020, with Hewitt’s (pump machinists) on-site doing other work, the impeller spacing on LLP3 was adjusted to see what difference of flows happened. It was found the impeller was likely showing signs of wear, and adjusted to get the best flow out of the pump. In February 2020, Tower Electronics was on site with a portable magmeter to measure LLP flow in the pipes. Flow was measured just after the in-line orifice flowmeter. The results found were flow rates more comparable to the expected pump capacities, and up to 10 L/s than what the current flow meter was giving. While the pipe composition and diameter can cause some discrepancies, it did draw the older differential flow meter readings a bit into questions. Tower Electronics is to return later in 2020 to do the existing flow meter calibrations and perform further investigations. Perth Drinking Water System Summary Report 2019 Page 20
As mentioned, the existing LLP pumps suffice for the current needs. Should either of the
lower sized LLP be in the need of replacement, a slightly larger capacity pump could
supply a better midrange operating range. The two existing pumps (~ 60-66 L/s) can
typically require 13-16 hours of daily operation to meet the current water demand. The
new MCC does allow the possibility for a reassessment of variable speed drives (VSD).
The raw water rate control valve and actuator needs repair and/or replacement. During
automation implementation, it was noted the rate control valve was failing at times. This
issue was mentioned in the 2018 Summary report, and no concrete actions taken in 2019
other than general conversations with contractors and very preliminary planning on project
feasibility. If the raw water orifice flow meter was needed to be upgraded to an in-line
magmeter (current industry standards), extensive header work will need to occur,
including any valve replacements at the time. In order to take the raw water header out of
service, significant operational planning would need to occur
HLP (High lift pumps, town water supply)
HLP#2 suffered significant pump failure in August 2019, the main drive shaft became
severed in the lower sections just above the impeller assemblies. After removing the
turbine pump from the service well, it was found that noticeable wear had also occurred to
the impellers (one had very significant damage). Both HLP#2 motor and pump assembly
were taken to Hewitt’s (Brockville), were further assessment was done. The entire pump
assembly components (shafts, couplers, impellers, bearings) were either replaced or
rebuilt. An electrical assessment and maintenance repair work was also done to the
motor. In January 202, HLP#2 was put back into service.
Pump Maintenance
In 2019, specialized machinists were brought in to perform the annual pump and motor
maintenance on both LLP and HLP’s. This was part of the initiating a preventative
maintenance approach for the pump operations, where a wider scope of work was done to
help identify problems well before they might occur.
Considerations with pumping capacity might be,
To continue to use specialized machinists in performing a predictive management
approach for both LLP and HLP operations, and an enhanced preventative
maintenance program for pump operations (oil changing, packing changing,
bearings inspection, check valve inspections, pressure relief valve inspections)
To further investigate RW rate control valve issues, and
To give further consideration to have a 10 HP motor readily available as a
replacement for either LLP2 or LLP3 operations.
Perth Drinking Water System Summary Report 2019 Page 213.1.8. Process Wastewater Residue Management ability
As indicated in the previous Summary reports,
a primary concern that could impact the ability to properly treat process residue
sludge would be incorporating Phase II, or Backwash Equalization Tank (BET)
volumes into the existing setup.
a secondary concern was the available greenhouse space for extended cold
weather use, especially with increased BET sludge volumes.
the inability to use outside geo-bags during moderately cold weather (>-10oC).
Ability to treat BET sludge
During 2019, it was felt the operations did have the ability to treat BET sludge, however it
required significant staff time to continually monitor the geo shed effluent and often
requiring mixing with settling tank sludge to get some type of consistency. Timing of the
backwashes is probably most important, juggling weekend settling tank sludge processing,
allowing sufficient settling time to remove supernatant, and have BET tanks empty again
for weekend sludge acceptance.
Moving into 2020, replacement of some of the newly installed devices with more reliable
units might allow staff to experience some form of automation which was initially promised.
Otherwise, the BET processes will continue to consume a significant portion of WTP staff
resources.
Geo bag operations
Despite being in a good preparation state to start 2019, we faced significant difficulties
once the greenhouse bag became unusable in early February. We were fortunate enough
to have some unseasonable warmer weather, and able to get to Bag 1 through until melt
conditions. Despite all the heat trace cables and other measures taken to continue to treat
to outside bags during colder temperatures, February 2019 did demonstrate our
vulnerability should greenhouse operations be compromised during a prolonged deep
freeze.
The larger circumference geo bags seem to work satisfactory outdoors; however, the pad
area does become full utilized with some water escaping away from the catchment area.
The smaller greenhouse bag size does limit our capacity, but allows clearance all around it
so that weeping promotion of the bag can occur.
Considerations with process wastewater residue management ability might be,
additional greenhouse capacity needs to be a priority consideration for the future to
allow,
o continued operations during extended colder temperature weather, and
o the ability to have two smaller bags to exist, giving a viable greenhouse bag
damage contingency plan
Perth Drinking Water System Summary Report 2019 Page 22 Security measures to be implemented around Phase II in-ground access areas and
outside geo bag deployments.
3.1.9. Computer System
Programming changes and upgrades to the WTP SCADA (Supervisory Control and Data
Acquisition) system occurred in 2019, mainly attributed to continuing facility automation
efforts and troubleshooting of operational alarms. Significant time was also spent
continuing linking with WWT SAGR automated operations into SCADA programming.
Other workplace priorities took on more importance in 2019 opposed to continuing with
operations automation and instrumentation installs. Focus on these efforts need to be re-
established in 2020. As newer instrumentation is being brought in, the reliance on a
digitalized communications network will become more prominent. The need for an
updated Ethernet or digitalized network mapping of the SCADA components is becoming
more realized.
SCADA and workplace computers were replaced in 2018, part of a 3-year program. In an
effort to make SCADA computers Windows 10 operational, they were again replaced in
late 2019, along with SCADA programming and off site notification. The pre-existing
SCADA software (Wonderware) and off site alarm notifications software (WIN911) was not
compatible with Windows 10 and needed replacing at significant cost. Also, the new
software versions were creating difficulties in trying to sync with Windows 10, issues
continuing into 2020, adding further to the transition costs. Significant expenses were also
spent in networking changes to accommodate digital telephone and communications use.
3.2. Water Taking Ability
The WTP is operating well within the PTTW limits. The Permit to Take Water (#5464-
6MHL84) authorizes the municipality to take water with maximum volumes regulated for
both litres/min as well as litres per day. This Permit was renewed in the 2016 year and
will expire again in 2026. Raw Water pump capacities determine these figures (6,360
l/min (106 L/s) flow; and 9,092 m3/day).
The maximum raw water flows in 2019 can both be attributed to a Town hydrant flushing
week occurring (5322 m3 on April 30, and 4896 m3 on October 08).
High volume times were noted during July 9-11 days (July 10 with 4323 m³, with an
average of 4022.3 m³ over the three days). A second higher volume time was noted over
August 20-21 (averaging 3867.0 m³/day). Both these times are reflective of use during
hot dry climate times, but still under 50% of the PTTW allowable volume for normal
operations). A more realistic daily maximum during a typical operating could easily be
estimated in the 3500 to 3900 m3 range (or approx. 41% of the PTTW).
Perth Drinking Water System Summary Report 2019 Page 233.3. Water Storage Ability
The reservoir was cleaned and inspected in May 2019, mostly for any degradation of the
wall adjacent to the 2018 construction area of the BET installation. Sections of the
clearwell (initial chlorine contact chamber) were inspected and cleaned during reservoir
valve work.
The reservoir storage capacity appeared to be sufficient to meet the disinfection contact
time needs, as well as providing required water supply for domestic, industrial, and fire
fighting purposes.
In 2019, the elevated tank past fluctuating tank level signals were less, but will be further
investigated in 2020. Operational set points at the WTP have been done to compensate
and continue with good water storage ability. Concerns have been raised regarding the
existing storage capacity of the current elevated tank, and its ability to meet any growing
needs of the Municipality.
Regular maintenance and emergency repairs occurred within the distribution system
including mains, services and hydrants.
Reservoir valve replacement program
Reservoir valve replacement program was resumed in 2019, once the Process
Wastewater Residue Management Phase II construction was finalized. The initial cost
estimates of 2015 have been well surpassed, any streamlining efforts to get the most
economical and feasible solutions possible available, including consideration of the do
nothing option for parts of the initial program objectives.
The following work was done in 2019,
The replacement reservoir influent valve encountered numerous difficulties during
installation, but became operational in June 2019.
Reservoir by-pass valve was blanked off and then removed in November 2019. A
new replacement valve has been ordered and should be delivered by April 2020.
Reservoir effluent valve was initially inspected in May 2019, then further work to
properly clean it and assess condition in November 2019. The condition was found
to be critically damaged, and removal difficulties will be very significant.
High priority items in 2020 for the reservoir involve,
Install the replacement reservoir by-pass valve,
Inspect and assess the secondary reservoir effluent valve (to Service well #2),
Assess options (possible Engineering consulting) regarding proceeding with the
reservoir effluent valve replacement and/or repair
Perth Drinking Water System Summary Report 2019 Page 243.4. Water Treatment and Distribution Personnel The WTP is a Class III facility. Basic automation implementation has allowed the transferring to 8-hour shifts to continue in 2019. Some additions to continuous monitoring of critical processes, along with off-site alarm advancements, has allowed weekend shifts to no longer regularly scheduled on a trial basis. While the shift scheduling becomes less, the workload associated with maintaining automated WTP operations increases. Key to this increased unmanned facility times, is the reliance of WTP operators to be on-call for immediate response to any WTP operational alarms, either through remote site communications or an actual site visit depending on the situation severity. Shifts and duties are rotated amongst two full time operators and a Lead Hand, all with WT Level III certifications. The Distribution system is a Class 1 facility and is maintained by a Lead Hand and five operators, who rotate through other departments within the organization. The Lead Hand possesses a level III certification in distribution and supply. Three (3) other operators have level II certification, one operator with level I certification, and one operator seeking operator in training status. Mention needs to be made that DWS staff also serve as WWS (wastewater system) operators. Distribution staff maintain the WWS collection system and its pumping stations. WTP staff are required to maintain the WWT facility, including the lagoon operations as well as a the SAGR facility and pumping station. Perth Drinking Water System Summary Report 2019 Page 25
Appendix
4.1 Appendix Table 1 – Summary of Flows January 1, 2019 to December 31, 2019
Perth Water Treatment Plant
PTTW maximum allowable flow rate: 9,092 m3/ day
Discharge (Service)
Raw water (m3)
Water (m3)
Monthly
Monthly
Monthly Daily Monthly Daily
Month Total
Average Flow Total Flow Average
Flow
Flow
January 3,071.6 95,220 2972.0 92,132
February 3,121.6 87,404 3035.9 85,005
March 3,138.1 97,281 3046.6 94,444
April 3,057.9 91,737 3037.7 91,131
May 3,056.7 94,759 3049.2 94,525
June 3,082.8 92,483 3062.4 91,871
July 3,472.9 107,660 3468.7 107,530
August 3,259.5 101,043 3228.3 100,076
September 2,884.7 86,540 2902.3 87,070
October 2,980.0 92,380 2912.4 90,284
November 2,795.4 83,861 2707.3 81,220
December 2,830.9 87,759 2710.6 84,028
Year Average 3,062.68 93,177.3 3,011.11 91,609.7
Year Total 1,118,127 1,099,316
Perth Drinking Water System Summary Report 2019 Page 26Perth Water Treatment Plant
2019 2018 2017 2016 2015 2014
JAN. 2972 2982 2,381 2,502 2,872 3,211
FEB. 3036 2890 2,454 2,571 3,290 2,980
MARCH 3047 2961 2,491 2,455 3,298 3,053
APRIL 3038 2983 2,586 2,471 3,157 3,247
MAY 3049 3363 2,495 2,931 3,392 3,003
JUNE 3062 3268 2,836 2,996 3,002 3,285
JULY 3469 3602 2,796 2,954 3,048 3,292
AUG. 3228 3269 2,837 3,024 3,015 3,099
SEPT. 2902 2947 2,886 2,694 2,979 2,992
OCT. 2912 2982 2,830 2,603 2,998 2,901
NOV. 2707 2840 2,568 2,372 2,852 2,693
DEC. 2711 2776 2,681 2,300 2,784 2,642
MAXIMUM 3,469 3,602 2,886 3,024 3,392 3,292
MINIMUM 2,707 2,776 2,381 2,300 2,784 2,642
AVERAGE 3,011 3,072 2,654 2,656 3,057 3,033
4.2 Appendix Table 2 – Historical Average Daily Treated Water Flow (m³)
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