assessment of water system infrastructure and water supply

Assessment of Water System Infrastructure and Water Supply Sources for the Town of Altona

Prepared for:

Town of Altona 111 Centre Avenue PO Box 1630 Altona MB R0G 0B0 Prepared by:

Stantec Consulting Ltd. 905 Waverley Street Winnipeg MB R3T 5P4

April 2009 File: 111211260

NOTICE OF COMPLETION OF AN ASSESSMENT OF WATER SYSTEM INFRASTRUCTURE AND WATER SUPPLY SOURCES FOR A PUBLIC WATER SYSTEM

TO BE COMPLETED BY THE OWNER: Date of Report: (yyyy/mm/dd)

Name of Water System: Community Code:

Category of Water System: Raw Water Source: (Surface/Groundwater/GUDI/Combined)

Location of Water System: Population Served:

Water System Owner Name: Telephone: Fax:

Water System Owner Address:

OPERATING LICENCE NUMBER AND DATE OF ISSUE (Where available) : As issued under the Drinking Water Safety Act

Operating Licence Number: Date of Issue: (yyyy/mm/dd)

I certify that: 1. The attached Report was prepared by a Professional Engineer who met the qualification

requirements as stipulated in the “Terms of Reference for Assessment of Water System Infrastructure And Water Supply Sources - For Public Water Systems”, and who is not an employee of the Water System Owner.

2. I have read the Report, and it is consistent with my understanding of the Water System.

3. I understand the Report to the best of my ability.

4. The information provided to the engineer, for the basis of this report, was accurate and complete to the best of my ability and knowledge.

The undersigned is the person, or the person designated by the Owner as being, responsible for the Water System:

Signature of Owner:

Name of Owner:

Title:

Date Signed:

ODW-AF-01A

ASSESSMENT OF WATER SYSTEM INFRASTRUCTURE AND WATER SUPPLY SOURCES FOR THE TOWN OF ALTONA

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Executive Summary

This report has been prepared to fulfill the requirements of Section 9 of the Drinking Water Safety Act (DWSA) for the Town of Altona (Town) Public Water System. Section 9 of the DWSA requires every public water system have an assessment conducted by a professional engineer every five years. The objective of this report is to conduct a review of the water system from source to tap. The report will characterize the source, describe the existing system, characterize the treated water, identify potential sources of contamination, assess the physical components of the water system and provide recommendations and conclusions.

The Altona Public Water System has an operating license that is valid until May 31, 2013. The water system has been classified as a Class II distribution system and is operated by two (2) Class II certified operators. There is no requirement for a Water Right’s License as the Town receives treated water from the Pembina Valley Water Cooperative (PVWC) Inc. There is also no waste discharged to the environment from the water system and therefore there is no need for an Environment Act License.

The Town receives treated water from the PVWC’s Red River Regional WTP located in Letellier. The Red River Regional WTP withdraws water from the Red River and treats it with a lime softening / filtration treatment process. Fluoride and chlorine are added to the filtered water before it is discharged to a storage reservoir. Treated water is distributed to the Town via a single supply line that splits off to the Town’s two reservoirs.

The South Reservoir was constructed in 1960 and includes a circular below ground concrete Reservoir with an internal Pump Chamber and Dry Pit. There is a building over the Pump Chamber and Dry Pit to house the distribution pumps, chemical feed equipment and electrical equipment. Chlorine is added to the treated water prior to entering the Reservoir by a manually operated chlorine feed pump. Treated water is distributed to the Town’s distribution system by two (2) vertical turbine distribution pumps. A third natural gas driven vertical turbine pump was previously operated during power outages and to provide fire flow. While this pump is generally not used since the North Reservoir was constructed with high flow pumps backed up by an emergency generator, it is operational.

The North Reservoir was constructed in 1994 and includes a partially buried concrete Reservoir and a Pump Station. The Pump Station is located approximately 40 meters north of the Reservoir and includes a Pump Chamber, lower level pipe gallery and a main floor. Chlorine is continuously fed based on an operators selected dose to the treated water prior to entering the Reservoir. Chlorine dose is manually adjusted based on the chlorine residual entering the distribution system. Treated water is distributed to the Town’s distribution system by four (4) vertical turbine pumps operating based on pressure in the distribution. An emergency generator backs up all the electrical loads at the North Reservoir in the event of a power failure.

ASSESSMENT OF WATER SYSTEM INFRASTRUCTURE AND WATER SUPPLY SOURCES FOR THE TOWN OF ALTONA EXECUTIVE SUMMARY April 1, 2009


In general the sustainability and reliability of the water system is good due to the redundancy provided for storage, distribution pumping and power supply. One item that requires attention in terms of reliability and general function is the pilot operated float valve on the pump chamber fill line. This valve does not operate when the reservoir is less than one third full and failure of this valve has resulted in flooding of the Pump Station.

The treated water received from the PVWC is in conformance with the Drinking Water Safety Act (DWSA) and Guidelines for Canadian Drinking Water Quality (GCDWQ) with the exception of Total Trihalomethanes (TTHM) and Bromodichlormethane (BDCM). TTHM and BDCM levels in the Town’s distribution system also exceed the DWSA and GCDWQ limits.

No direct sources of contamination were noted in the water system. Potential sources of contamination noted were the overflows at the North Reservoir and North Reservoir Pump Station connected directly to the wastewater sewer, flooding of the North Reservoir Pump Station and the float valve access hatch at the South Reservoir. There has only been one occurrence in the past five years where a positive total coliform reading was noted in the distribution system.

The water system was reviewed with respect to the DWSA (March 2007) and the Ten State Standards (2007) and was found to be noncompliant with respect to:

• Free chlorine level entering the Town’s distribution system.

• TTHM and BDCM level in the Town’s distribution system.

• Overflows for the Reservoir and Pump Chamber at the North Reservoir.

• Float valve access hatch at the South Reservoir is not curbed or gasketed and bolted.

• Spill containment for chlorine at the South Reservoir.

• 24 hour monitoring of the Reservoir high and low levels.

The following recommendations could be implemented to improve compliance and reliability of the water system:

• Replace the pilot operated float control valve on the Pump Chamber fill line at the North Reservoir with two electrically operated butterfly valves and provide manual bypass.

• Install a chlorine residual analyzer on the distribution header at both the South and North Reservoir to provide continuous monitoring of the chlorine residual entering the distribution system.

ASSESSMENT OF WATER SYSTEM INFRASTRUCTURE AND WATER SUPPLY SOURCES FOR THE TOWN OF ALTONA EXECUTIVE SUMMARY April 1, 2009


• Add an additional chlorine feed pump operated based on a continuous feedback loop with the chlorine analyzer to dose additional chlorine as required to maintain a residual greater than 0.5 mg/L entering the distribution.

• Investigate options, such as reducing Total Organic Carbon (TOC) in the treated water or an alternative primary disinfection method in combination with chlorination optimization, to reduce the TTHM and BDCM levels in the treated water received from the PVWC.

• Install new overflows for the Reservoir and Pump Chamber at the North Reservoir.

• Install curbing around the float valve access hatch at the South Reservoir.

• Provide spill containment for the chlorine barrels at the South Reservoir.

• Install an autodialer to notify the operators when critical alarms, such as the Reservoir high and low level alarms, are triggered.


Table of Contents

EXECUTIVE SUMMARY E.1

1.0 CERTIFICATES, PERMITS AND LICENSES ....................................................................1.1 1.1 OPERATING LICENCE ......................................................................................................1.1 1.2 CERTIFICATES OF APPROVAL........................................................................................1.1 1.3 WATER RIGHTS LICENCE................................................................................................1.1 1.4 ENVIRONMENTAL ACT LICENCE ....................................................................................1.1

2.0 WATER SUPPLY SOURCE CHARACTERIZATION.........................................................2.1 2.1 WATER SOURCE...............................................................................................................2.1

2.1.1 Primary Water Source..........................................................................................2.1 2.1.2 Backup Water Source ..........................................................................................2.1

2.2 DESCRIPTION OF SOURCE PROTECTION ....................................................................2.1 2.3 CHARACTERIZATION OF RAW WATER IN TERMS OF CONFORMANCE TO

PROVINCIAL STANDARDS ...............................................................................................2.1

3.0 DESCRIPTION OF THE WATER SYSTEM AND OPERATION ........................................3.1 3.1 BACKGROUND ..................................................................................................................3.1 3.2 DESCRIPTION OF THE WATER SYSTEM .......................................................................3.1

3.2.1 Detailed Description.............................................................................................3.1 3.2.1.1 North Reservoir....................................................................................................3.1 3.2.1.2 South Reservoir ...................................................................................................3.4 3.2.1.3 Distribution System..............................................................................................3.5 3.2.2 Summary of Facility’s “Log Credits” .....................................................................3.6 3.2.3 Disinfection CT Calculations ................................................................................3.6

3.3 REVIEW OF MONITORING EQUIPMENT .........................................................................3.6 3.3.1 North Reservoir....................................................................................................3.6 3.3.2 South Reservoir ...................................................................................................3.7

3.4 SUMMARY OF WATER SYSTEM SUSTAINABILITY AND RELIABILITY.........................3.8 3.5 SUMMARY OF OPERATOR AND STAFF CERTIFICATION.............................................3.9 3.6 SUMMARY OF WATER PRODUCTION AND CONSUMPTION........................................3.9

4.0 TREATED WATER CHARACTERIZATION.......................................................................4.1 4.1 CHARACTERIZATION OF TREATED WATER IN TERMS OF CONFORMANCE TO

PROVINCIAL STANDARDS ...............................................................................................4.1 4.2 CHARACTERIZATION OF THM AND OTHER DISINFECTION BY-PRODUCTS IN THE

TREATED WATER .............................................................................................................4.3

5.0 ASSESSMENT OF THE POTENTIAL FOR MICROBIAL, CHEMICAL AND PHYSICAL CONTAMINATION .............................................................................................................5.1

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Table of Contents 5.1 ASSESSMENT OF THE POTENTIAL FOR CONTAMINATION AT THE WATER

SOURCE.............................................................................................................................5.1 5.1.1 Site Visit and Inspection Findings ........................................................................5.1 5.1.2 Review of Bacteriological Data ............................................................................5.1

5.2 ASSESSMENT OF THE POTENTIAL FOR CONTAMINATION IN THE TREATMENT PROCESS ..........................................................................................................................5.1 5.2.1 Inspection Findings and System Details ..............................................................5.1

5.3 ASSESSMENT OF THE POTENTIAL FOR CONTAMINATION IN THE DISTRIBUTION SYSTEM .............................................................................................................................5.1 5.3.1 Inspection Findings and System Details ..............................................................5.1 5.3.2 Review of Bacteriological data.............................................................................5.2 5.3.3 Review of Monitoring Programs...........................................................................5.2 5.3.4 Review of Cross Connection and Backflow Prevention Programs ......................5.3 5.3.5 Review of Emergency Contingency Plans ...........................................................5.3

6.0 ASSESSMENT OF PHYSICAL WORKS ASSOCIATED WITH THE WATER SYSTEM ..6.1 6.1 SUMMARY OF PHYSICAL WORKS ..................................................................................6.1 6.2 ABILITY TO COMPLY WITH REGULATIONS ...................................................................6.1

6.2.1 Drinking Water Safety Act....................................................................................6.1 6.2.1.1 Disinfection and Testing.......................................................................................6.1 6.2.1.2 Testing and Record Keeping ...............................................................................6.2 6.2.1.3 Sampling and Analysis.........................................................................................6.2 6.2.2 Ten State Standards ............................................................................................6.2

6.3 RECOMMENDATIONS FOR IMPROVEMENTS FOR COMPLIANCE ..............................6.3

7.0 SUMMARY OF CONCLUSIONS AND RECOMMENDATIONS ........................................7.1

8.0 STANTEC QUALITY CONTROL .......................................................................................8.1 APPENDICES APPENDIX A - Operating License APPENDIX B - Operator Certificates APPENDIX C - Water Quality Data APPENDIX D - Disinfection By-Product Data APPENDIX E - Chlorine Data

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1.0 Certificates, Permits and Licenses

1.1 OPERATING LICENCE

An Operating License (License No. PWS-08-153) was issued for the Altona Public Water System on June 1, 2008. The license is valid until May 31, 2013. The license governs the operation of the water system and a copy is included in Appendix A.

1.2 CERTIFICATES OF APPROVAL

The Altona Public Water System is operated and maintained by the Town of Altona Public Works Department. The water system has been deemed a Class II distribution system by Manitoba Conservation and is operated by two certified operators. The operators and their certificates are summarized below. Copies of the certificates are included in Appendix B.

Wayne Dueck Class I Water and Wastewater Treatment Class II Water Distribution and Wastewater Collection

Donald Braun Class I Water and Wastewater Treatment Class II Water Distribution and Wastewater Collection

1.3 WATER RIGHTS LICENCE

The Altona Public Water System receives treated water from the Pembina Valley Water Cooperative (PVWC) Inc. and therefore does not require a Water Rights License.

1.4 ENVIRONMENTAL ACT LICENCE

The Altona Public Water System does not discharge process water or wastewater to the environment and therefore does not require an Environmental Act License.

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2.0 Water Supply Source Characterization

2.1 WATER SOURCE

2.1.1 Primary Water Source

The Altona Water System receives treated water from the PVWC. The PVWC consists of three (3) Water Treatment Plants (WTP) that supply treated water to a population base of 45,000 people over an area of approximately 9,000 square kilometers. The Altona Public Water System is supplied water from the Red River Regional WTP located in Letellier. The Red River Regional WTP withdraws water from the Red River and treats it with a lime softening / filtration treatment process. Fluoride and chlorine are added to the filtered water before it is discharged to a storage reservoir. From the reservoir, the treated water is distributed to the PVWC’s municipal customers. There is one supply line from the Red River Regional WTP that is metered as it enters the Town of Altona (Town) and then splits off into two lines to feed the Town’s two (2) distribution reservoirs.

2.1.2 Backup Water Source

There is no back-up water source for the Altona Public Water System.

2.2 DESCRIPTION OF SOURCE PROTECTION

The PVWC is responsible for operation and maintenance of the water supply line to the Town’s distribution reservoirs and therefore is responsible for protection of the water supply source. The source is disinfected and a chlorine residual is maintained in the supply water to ensure there is no bacteria re-growth in the supply line.

2.3 CHARACTERIZATION OF RAW WATER IN TERMS OF CONFORMANCE TO PROVINCIAL STANDARDS

The Altona Public Water System does not receive raw water. Characterization and discussion related to the treated water is discussed in Section 4.0.




3.0 Description of the Water System and Operation

3.1 BACKGROUND

A single distribution reservoir (currently referred to as the South Reservoir) was constructed in 1960. This reservoir was fed treated water from the Neche WTP approximately 15 km south of Altona in North Dakota. The treated water was re-chlorinated and distributed to the Town. In 1994 a new distribution reservoir (currently referred to as the North Reservoir) was constructed. At this time the treated water supply source was changed from the Neche WTP to the PVWC. While the North Reservoir was constructed to enable it to be fed treated water from either the PVWC or the Neche WTP, the Neche WTP has subsequently been decommissioned and the supply line that previously fed treated water to Altona from Neche is now used by the PVWC to feed treated water to the Town of Gretna.

The current system, described in the following section, consists of two distribution reservoirs that receive treated water from the PVWC, re-chlorinate treated water and distribute it to approximately 3,700 residents and some large industrial customers.

3.2 DESCRIPTION OF THE WATER SYSTEM

3.2.1 Detailed Description

The following text provides a detailed description of the water system and the design and operational parameters. Refer to Figure 3.1 for a process flow diagram of the water system.

3.2.1.1 North Reservoir

The North Reservoir is comprised of a partially buried concrete Reservoir and a Pump Station. The Pump Station is located approximately 40 meters north of the Reservoir and includes a Pump Chamber, lower level pipe gallery and a main floor.

Treated Water Reservoir Fill

Treated water from the PVWC passes through the lower level pipe gallery on route to filling the Reservoir. The treated water Reservoir fill line is metered using a Pulsed Turbine Flow Meter and controlled via an open / closed solenoid control valve. The solenoid valve is opened when the reservoir level drops below a Programmable Logic Controller (PLC) programmable set point (6375mm) and closed when the level reaches another PLC programmable set point (6545mm). Level in the reservoir is monitored using a pressure sensor / transmitter.

The instantaneous flow is displayed on the control panel and is used to flow pace supplemental chlorine feed. The instantaneous flow is also recorded using a chart recorded and the cumulative flow is displayed on the control panel. The flow from the PVWC varies depending

ASSESSMENT OF WATER SYSTEM INFRASTRUCTURE AND WATER SUPPLY SOURCES FOR THE TOWN OF ALTONA Description of the Water System and Operation April 1, 2009


whether other communities are also drawing water from the PVWC at the same time. The operators currently have throttled a butterfly valve on the reservoir fill line to slow the flow rate and subsequently the fill time. The set point was achieved through optimization of the PWVC system and the Town’s system.

Chlorination

While the treated water from the PVWC enters the reservoir with a chlorine residual, additional chlorine is added to ensure that the chlorine residual in the treated water discharged to the Town’s distribution system has a chlorine residual greater than 0.5 mg/L. Sodium hypochlorite (12%) is used to maintain the required chlorine residual in the treated water. A single Grundfos diaphragm pump rated at 3.3 L/hr is used to inject chlorine into the reservoir fill line. The operators report that there is a shelf spare common to both the North Reservoir and South Reservoir.

The chlorine feed pump can be operated either in manual mode or automatic mode. In manual mode the chlorine is dosed at a constant rate independent of flow in the reservoir fill line. In automatic mode the chlorine feed concentration is kept consistent as the chlorine feed rate is flow paced based on flow in the reservoir fill line. The operators manually adjust the stroke length and rate based on the readings of the free chlorine taken on a daily basis from the distribution header at the Pump Station.

Reservoir

The reservoir is 21.45 m x 21.45 m x 7.5 m (l x w x d) for a total volume of 3,451 m3. The operating depth is 7.0 m for an active volume of 3,222 m3. The reservoir fill level is monitored using a pressure sensor / transmitter. This signal is sent to the PLC in the Pump Station and used to open and close the solenoid valve on the reservoir fill line. The reservoir also has hard wired electrodes to indicate and alarm when certain levels are reached. The reservoir set points are as follows:

High Level Alarm (electrode) 6865 mm Reservoir Full (electrode) 6850 mm Reservoir Fill Stop (ultrasonic) 6545 mm Reservoir Fill Start (ultrasonic) 6375 mm Low Level Alarm (electrode) 1817 mm

The reservoir has a 300ø overflow that discharges directly to the wastewater sewer. The overflow consists of a pipe open ended at a reservoir level of 7050 mm. It is apparent from visual observation that the elevation of the overflow is greater than the top of the wastewater sewer manhole.



The 200ø reservoir fill pipe discharges to the southwest corner of the Reservoir. The Reservoir is not baffled and the 350ø outlet pipe to the Pump Chamber withdraws treated water from the northeast corner of the Reservoir.

Pump Chamber

The pump chamber is 7.4 m x 3.1 m x 5.8 m (l x w x d) for a total volume of 133 m3. The 350ø pump chamber fill pipe passes through the lower level pipe gallery before discharging to the pump chamber. The top floor of the pump chamber is lower than the reservoir and therefore flow between the reservoir and pump chamber requires control. Control is achieved through a pilot operated float control valve. When the level in the pump chamber drops, a float in the pump chamber is tripped. When the float is tripped the water line to the control valve located on the pump chamber fill line is depressurized and the valve is opened to fill the pump chamber.

The pump chamber has a 300ø overflow that discharges directly to the wastewater sewer. The overflow line has two wafer check valves (in series) with external lever and weights that are visible in the lower pipe gallery. It appears as though the elevation of the overflow is lower than that of the surrounding grade and therefore the top of the wastewater sewer manhole.

The operators report that the pilot operated float control valve does not remain open when the reservoir level is less than one-third full due to insufficient head on the upstream side of the valve. This decreases the useful volume of the reservoir.

Distribution Pumping System

The distribution pumping system is comprised of 4 vertical turbine pumps. P1 and P2 are each capable of producing 17 L/s, while P3 and P4 are each capable of producing 85 L/s. The pumps operate based on pressure in the distribution system as indicated in Table 3.1.

Table 3.1 – Distribution Pumping Sequence of Operation

Pump Start Pressure Stop PressureP1 68 psi 78 psi

P2 63 psi 73 psi

P3 52 psi 73 psi

P4 45 psi 65 psi

A pressure reducing valve is installed on the distribution pump header to ensure a steady pressure in the distribution system. The distribution pumps feed the Town’s distribution system, a truckfill, and the Pump Stations domestic water line. A double backflow preventer is installed upstream of the truckfill and domestic water line take off to prevent contamination.



The distribution line is metered using a Pulsed Electronic Turbine Flow Meter. The instantaneous flow is displayed on the control panel and recorded by a chart recorder, while the cumulative flow is also displayed on the control panel.

Generator

There is a 175 kW diesel generator that is capable of backing up the entire electrical load for the Pump Station. When there is a power outage the generator automatically turns on and powers the entire Pump Station.

3.2.1.2 South Reservoir

The South Reservoir is comprised of a circular below ground concrete reservoir with an internal pump chamber and dry pit. There is a building over the pump chamber and dry pit, which houses the distribution pumps, chemical feed equipment, and electrical equipment.

Treated Water Reservoir Fill

Treated water from the PVWC is distributed from a Valve Building (owned and operated by the PVWC) located on an adjacent property. Treated water enters the South Reservoir through the Dry Pit and then discharges 6 meters into the circular reservoir via a 150ø pipe. The treated water reservoir fill line is metered using a Pulsed Electronic Turbine Flow Meter and controlled via an open / closed float control valve. The flow meter is located in the PVWC Valve Building. The instantaneous flow and cumulative flow is displayed on the control panel in the Valve House.

The float control valve is located in the South Reservoir building. The float control valve opens when the float located in the Pump Chamber drops and closes when the reservoir is full. There is also an option to bypass the reservoir and directs treated water from the PVWC directly to the Pump Chamber if the Reservoir is out of Service for maintenance. There is no flow pacing or automatic operation of this pump.

Chlorination

Sodium hypochlorite (12%) is used to maintain a chlorine residual in the treated water. The treated water reservoir fill line is chlorinated using a single Grundfos diaphragm pump rated at 1.9 L/hr. The operators report that there is a single shelf spare that is common to both the North and South Reservoirs.

The chlorine feed pump can only be operated manually. The operators run the chlorine feed pump as required to maintain a chlorine residual greater than 0.5 mg/L in the water discharged to the distribution system. The operators manually adjust the stroke length and rate based on the readings of the free chlorine taken from the distribution header at the South Reservoir.



Reservoir

The Reservoir is 22 m in diameter and 4.3 meters deep for a total volume (excluding the Dry Pit and Pump Chamber) of approximately 1,560 m3. The reported active volume is 1,453 m3, which would include approximately 0.5 meters of dead storage. The Pump Chamber is 1.1 meters deeper than the reservoir to minimize dead storage at the bottom of the Reservoir that results from the minimum water level required for the vertical turbine pumps to operate.

The Reservoir has 3 – 100ø overflow pipes that discharge to an overflow structure and then to the ditch. There is a 6mm bird screen on the end of the overflow pipes.

The 150ø reservoir fill pipe discharges 6 m towards the center of the 22 m circular reservoir. There are no intra-reservoir baffles and the Reservoir discharges to the Pump Chamber via a 200ø pipe located immediately adjacent the Pump Chamber.

Pump Chamber

The Pump Chamber has an interior dimension of 3.0 m x 4.6 m x 5.4 m (l x w x d) for a total volume (excluding the dry pit) of approximately 60 m3. The Pump Chamber is 1.1 meters lower than the reservoir to minimize dead storage in the reservoir that results from the minimum water level required to operate the vertical turbine pumps. The pump chamber is hydraulically connected to the reservoir and therefore the reservoir overflow provides overflow protection for the pump chamber as well. The pump chamber has hardwired floats to alarm under high level, low level and pump lockout conditions.

Distribution Pumping System

The distribution pumping system is comprised of 3 vertical turbine pumps. P1 and P2 are each capable of producing 19 L/s, while P3 is a natural gas driven vertical turbine pump capable of producing 57 L/s. The lead pump is run manually and operates at all times. The lag pump is operated based on pressure in the distribution system. It is set to start when the pressure drops to 55 psi and stop when the pressure increases to 65 psi. Pump P3 previously operated under power outages, but generally does not operate any more as the emergency generator at the North Reservoir can operate the pumps (including the high flow pumps) at the North Reservoir in case of power outage.

The distribution line to the Altona’s distribution system is not metered. Water produced at this station is recorded using the Pulsed Electronic Turbine Meter on the reservoir fill line.

3.2.1.3 Distribution System

The distribution system is comprised of approximately 27.2 km of pipe. Approximately 61% is Asbestos Cement (AC) pipe, 38% is Polyvinyl Chloride (PVC) pipe and 1% is High Density Polyethylene (HDPE) pipe. There are 140 fire hydrants. There are approximately 1200 service



connections and they do not include backflow preventers (with the exception of the large industrial customer Bungi foods).

3.2.2 Summary of Facility’s “Log Credits”

The Altona Public Water System receives treated water from the PVWC. The “Log Credits” for protozoa and viruses provided through treatment at the Red River Regional WTP are as indicated in Table 3.2. Credits for treatment are in accordance with those noted in the GCDWQ’s Supporting Document for Protozoa: Giardia and Cryptosporidium (April 2004). It has been assumed that sufficient chlorine contact time is provided to achieve the chlorination credits noted.

Table 3.2 – Credits for Protozoa and Viruses

Treatment Technology Giardia Credit Crypto Credit Virus CreditConventional Chemically Assisted Filtration

3.0 log 3.0 log 2.0 log

Chlorination 0.5 log 0 log 4.0 log

Total 3.5 log 3.0 log 6.0 log

3.2.3 Disinfection CT Calculations

As treated water is provided from the PVWC, disinfection CT calculations are not required for the Altona Public Water System.

3.3 REVIEW OF MONITORING EQUIPMENT

3.3.1 North Reservoir

The North Reservoir has the following monitoring equipment:

Pulsed Electronic Turbine Flow Meters: Flow meters are provided on the treated water reservoir fill line and the treated water distribution line. Instantaneous flow is displayed in the control panel and recorded by a chart recorder. Cumulative flow is displayed in the control panel. The flow on the reservoir fill line is used to flow pace supplemental chlorine feed.

Reservoir Pressure Sensor /Transmitter: A pressure sensor / transmitter translates pressure in the reservoir fill pipe to the level in the reservoir. Instantaneous level in displayed in the panel and is used to open and close the solenoid valve on the reservoir fill line.



Electrodes: Electrodes are used to indicate high level, reservoir full and low level in the pump chamber. When these pump chamber levels are triggered it is displayed with a red light in the control panel and by a visual and audible alarm at the Pump Station.

Pressure Switches: Four (4) pressure switches are used to control the operation of the pumps. Refer to Section 3.2.1.1 for pressure settings.

Distribution Pressure Sensor: A pressure sensor located off the distribution header monitors the pressure in the distribution system. The instantaneous pressure is displayed in the panel and recorded by the chart recorder.

PLC: The PLC monitors equipment operation and alarms visually and audibly. Alarms that are provided are as follows:

- North Reservoir High Level - North Reservoir Low Level - North Reservoir Empty - South Reservoir High Level - South Reservoir Low Level - South Reservoir Empty - North Pump Chamber High Level - North Pump Chamber Low Level

- North Pump Chamber Empty - North Reservoir P1 Overload - North Reservoir P2 Overload - North Reservoir P3 Overload - North Reservoir P4 Overload - South Reservoir P1 Overload - South Reservoir P2 Overload - Generator Low Fuel

Hach Colour Wheel: a portable colour wheel is used to indicate the free available chlorine concentration in the sampled water. This instrument is used for both the North and South Reservoirs.

Building Flood Alarm: A float located in the sump pit provides indication of a building flood. The alarm is visual and audible.

3.3.2 South Reservoir

Pressure Switches: One (1) pressure switches is used to control the operation of the pumps.

Floats: Three (3) Miltronics floats are used to indicate high level, low level and reservoir empty in the pump chamber. When these levels are triggered it is displayed with a red light in the control panel at the North Reservoir and by a visual and audible alarm at the North Reservoir. Telemetry is used to convey these signals to the North Reservoir.

Building Flood Alarm: A float located in the dry pit provides indication of a building flood. The alarm is visual and audible at the North Reservoir. Telemetry is used to convey these signals to the North Reservoir.



3.4 SUMMARY OF WATER SYSTEM SUSTAINABILITY AND RELIABILITY

Water Source: The PVWC treats water from the Red River and therefore the long term sustainability of the raw water source is high. The water supply to Altona could be interrupted by a watermain break on the single supply line. The risk of a supply line watermain break interrupting service to the Town of Altona is low as there is approximately three (3) average days of storage in the Town’s two Reservoirs.

Chlorination: The South Reservoir chlorine dosing system is manual and therefore relies on continuous operation attention to maintain optimal chlorine residual in the distribution system. The North Reservoir chlorine system is automatic and turns on only when there is flow in the pipe. The operators are still required to adjust the dose to maintain an optimal residual in the distribution system. Both chlorine feed pumps are in satisfactory condition and a shelf spare is available if either of the chlorine feed pumps were to fail.

Storage: The South Reservoir is approximately 48 years old. Even if this reservoir was taken out of service to repair a leak the risk of having an impact on the supply to Town of Altona is low as the North Reservoir alone provides approximately 2 average days of storage.

The North Reservoir is only 15 years old. The operators report that the valve that controls feed of treated water from the Reservoir to the Pump Chamber does not open when there is less than one third of the volume remaining. This reduces the useful volume of the North Reservoir. The operators also report that this valve has failed to close previously and resulted in the flooding of the Pump Station. They have since installed a float in the Lower Level Pipe Gallery to alarm when there is flooding.

Distribution Pumping: The distribution pumping at the South Reservoir is original and while currently working, may need replacement in the near future due to its age. The distribution pumps at the North Reservoir are approximately 15 years old and appear in reasonable condition. The risk of a service interruption resulting from a pump failure at either reservoir is low as there is a backup pump at the South Reservoir and four (4) additional pumps at the North Reservoir that would turn on in response to a pressure reduction in the distribution system. The pumps at the North Reservoir are also backed up by an Emergency Generator and would continue to operate under a power failure. The North Reservoir has been designed to allow for the installation of an additional pump should the demand in the distribution system increase.

Alarming: Critical operations (refer to Section 3.31 for list of alarms) at both reservoir are alarmed at the North Reservoir. The alarms are noted visually by a beacon and audibly by a horn outside the North Reservoir. The operators indicated that they are called by nearby residents who see or hear the alarms. This is a potential risk to the reliability of the system as it might take a number of hours for an operator to be notified if there is a critical operational failure in the middle of the night.


3.5 SUMMARY OF OPERATOR AND STAFF CERTIFICATION

Refer to Section 1.2 for a summary of operator certification.

3.6 SUMMARY OF WATER PRODUCTION AND CONSUMPTION

Water consumption at the North and South Reservoirs are monitored on a daily basis. The total annual water consumption for the past three years is presented in Table 3.3 and the monthly consumption is summarized in Figure 3.1. The consumption presented is the total combined consumption from both the North and South Reservoir.

Table 3.3 – Annual Water Consumption Reported for 2006 to 2008.

Year Total Annual Consumption

Annual Average Day Consumption

Per Capita Consumption

2006 597,140 m3 1,636 m3/d 441 L/capita/d 2007 612,105 m3 1,677 m3/d 452 L/capita/d 2008 615,978 m3 1,683 m3/d 453 L/capita/d

The per capita water consumption was calculated using a total population of 3,709 and is higher than the typical Canadian average of 270 L/cap/d. It is suspected that the per capita consumption is inflated due to industrial users such as Bungi Foods.

0

500

1,000

1,500

2,000

2,500

Janu

ary

Februa

ryMarc

hApri

lMay

June Ju

ly

Augus

t

Septem

ber

Octobe

r

Novem

ber

Decem

ber

Month

Mon

thly

Ave

rage

Flo

w (m

3/d)

2006 2007 2008

Figure 3.3 – Historic Annual Water Consumption




As can be seen in Figure 3.3, the water consumption is fairly consistent year to year and month to month. There is a slight increase in the summer month, which is typical with Municipal water consumption.



4.0 Treated Water Characterization

4.1 CHARACTERIZATION OF TREATED WATER IN TERMS OF CONFORMANCE TO PROVINCIAL STANDARDS

The treated water characteristics are summarized in Table 4.1. The table summarizes the historical treated water quality from the Red River Regional WTP based four data sets provided by the PVWC from 2005 to 2008 and compares it to the provincial DWSA and GCDWQ limits. Complete treated water quality results are included in Appendix C. The parameters that exceed the DWSA and GCDWQ limits are bromodichloromethane (BDCM) and total trihalomethanes (TTHM). These parameters are discussed further in Section 4.2 – Characterization of THM and Other Disinfection By-products in the Treated Water. While the data for the treated water supply from the PVWC indicates that Haloacetic acids are below the prescribed limit, this is based on one sample set only. The Haloacetic acid limit of 0.08 mg/L was adopted by the GCDWQ in July, 2008. The DWSA does not regulate haloacetic acid.

ASSESSMENT OF WATER SYSTEM INFRASTRUCTURE AND WATER SUPPLY SOURCES FOR THE TOWN OF ALTONA Treated Water Characterization April 1, 2009


Table 4.1 – Characteristics of the Treated Water Provided to the Altona Water System

Parameter Unit Treated Water DWSA & GCDWQ Min Max MAC AO/OG Arsenic mg/L 0.0007 0.0009 0.01c Bicarbonate (HCO3) mg/L 48.8 94.2 Bromodichloromethane mg/L 0.019 0.032 0.016d Carbonate (CO3) mg/L < 0.5 < 0.5 Chloride mg/L 25.1 34.4 250 Conductivity umhos/cm 482 591 Copper mg/L 0.0041 0.12 1 Fluoride mg/L 0.69 0.85 1.5c Haloacetic acids mg/L 0.005 0.005 0.08 Hardness (Total) CaCO3 mg/L 128 147 200/500 a

Hydroxide (OH) mg/L < 0.5 < 0.5 Iron mg/L < 0.01 0.16 0.3 Lead mg/L < 0.0008 0.0005 0.01 Manganese mg/L 0.0004 0.01 0.05 Nitrate and Nitrite mg/L < 0.01 0.043 10 pH pH units 7.24 7.77 6.5 - 8.5 Sodium mg/L 47 59.5 200 Sulphate mg/L 133 154 500 Total Trihalomethanes mg/L 0.105 0.415 0.1d Total Alkalinity (CaCO3) mg/L 40 77.2 Total Organic Carbon mg/L 3.4 9.0 True Color mg/L < 5 < 5 Turbidity NTU < 0.1 0.1 1/0.3/0.1 b

Zinc mg/L 0.001 0.009 5

AO = Aesthetic Objective

MAC = Maximum Acceptable Concentration OG = Operational Guideline

a Hardness levels greater than 200 are considered poor, but tolerable, while hardness levels greater than 500 are generally considered unacceptable. b Dependant on treatment process: Slow sand filtration / Chemically assisted filtration / Membrane filtration c Groundwater source only. d Surface water source only.

ASSESSMENT OF WATER SYSTEM INFRASTRUCTURE AND WATER SUPPLY SOURCES FOR THE TOWN OF ALTONA Treated Water Characterization April 1, 2009


4.2 CHARACTERIZATION OF THM AND OTHER DISINFECTION BY-PRODUCTS IN THE TREATED WATER

As noted in Section 4.1, the water provided to the Town from the PVWC has on occasion exceeded the DWSA TTHM limit of 0.1 mg/L and the BDCM limit of 0.016 mg/L. The DWSA limit is based on sampling on a quarterly average and therefore the single sample per year provided by the PVWC is insufficient to determine if the treated water provided to the Altona Public Water System is in conformance with the DWSA.

The Town has taken quarterly TTHM samples from the distribution system and the results are summarized in Table 4.2. Complete sampling results are provided in Appendix D.

Table 4.2 – Quarterly TTHM Results Sampling Results from the Distribution System

TTHM (mg/L) BDCM (mg/L)

1st Qr. 2nd Qr. 3rd Qr. 4th Qr. Qr. Avg. 1st Qr. 2nd Qr. 3rd Qr. 4th Qr. Qr. Avg.2007 0.066 0.134 0.11 0.12 0.11 0.027 0.03 0.038 0.042 0.034 2008 0.15 0.092 0.11 0.14 0.12 0.044 0.022 0.019 0.044 0.032

Sampling results from the distribution system indicate that both the quarterly TTHMs and the quarterly BDCMs in the distribution exceed the DWSA limits those prescribed in the operating license. The Altona Public Water System license requires the Town to submit a compliance plan on how they intend to conform to the DWSA TTHM and BDCM limits by June 1, 2009.

As noted in Section 4.1, the TTHM and BDCM data for the supply water indicates that it sometimes exceeds the DWSA limits. The Altona Public Water System is adding only minimal quantities of chlorine to ensure they meet the DWSA regulation of 0.5 mg/L free chlorine entering the distribution system. While adding adsorption (via Granular Activated Carbon (GAC) filtration) or air stripping are possible means to reduce TTHMs entering the Town’s Reservoirs, a more practical solution is to mitigate the problem at the source. While not part of the scope of work for this assessment, potential solutions that the Red River Regional WTP could potentially investigate to reduce the TTHM and BDCM levels in the treated water supply are a reduction of Total Organic Carbon (TOC) in the treated water or an alternative disinfection technology, such as UV disinfection with optimization of the chlorine dose.



5.0 Assessment of the Potential for Microbial, Chemical and Physical Contamination

5.1 ASSESSMENT OF THE POTENTIAL FOR CONTAMINATION AT THE WATER SOURCE

5.1.1 Site Visit and Inspection Findings

The treated water supply is operated and maintained by the PVWC and was not inspected as part of this assessment. Assessment of the PVWC’s supply system would be through the PVWC’s Engineering Assessment.

5.1.2 Review of Bacteriological Data

The treated water supplied by the PVWC is sampled prior to entering the South Reservoir on a biweekly basis by the operators and sent to ALS Laboratories Group for analysis for Total Coliform and E.Coli. There has been no positive result noted for Total Coliform or E. Coli in the past five years.

5.2 ASSESSMENT OF THE POTENTIAL FOR CONTAMINATION IN THE TREATMENT PROCESS

5.2.1 Inspection Findings and System Details

There is no treatment process for the Altona Public Water System.

5.3 ASSESSMENT OF THE POTENTIAL FOR CONTAMINATION IN THE DISTRIBUTION SYSTEM

5.3.1 Inspection Findings and System Details

A visual inspection of the North Reservoir, Pump Station and South Reservoir was conducted on February 17, 2009. There was no evidence of direct contamination of the treated water storage or distribution system. Potential pathways of contamination include:

• The Pump Chamber overflow at the North Reservoir discharges directly to the wastewater sewer (WWS). Confirmation of the grade of the top of the WWS manhole’s adjacent the Pump Chamber in relation to invert of the overflow is required to determine the severity of this risk. If the WWS manhole rim is higher than the invert of the overflow and the WWS was to become plugged, it posses a higher risk as could backup and contaminate the Reservoir. Even if the manhole rim is lower than the overflow elevation WWS pressurization poses a risk. There are weighted check valves on the overflow line that minimize this risk, but there is no assurance that they provide a 100% seal.

ASSESSMENT OF WATER SYSTEM INFRASTRUCTURE AND WATER SUPPLY SOURCES FOR THE TOWN OF ALTONA Assessment of the Potential for Microbial, Chemical and Physical Contamination April 1, 2009


• Flooding of the Pump Station main floor over the height of the Pump Chamber access hatch curb could contaminate the Pump Chamber. The operators reported that the PVC elbows at the Pump Station have broken in the past and resulted in flooding out the door of the Pump Station main floor. A significant volume of water would be discharged as all of the pumps would be called to operate to maintain the low distribution system pressure.

• The pilot operated float control valve on the Pump Chamber fill line has also failed to close in the past. This has resulted in Pump Station flooding because the overflow for the Pump Chamber is of a smaller diameter then the Pump Chamber fill line and the head required to open the two check valves sufficiently is not available.

• The float valve access hatch located above the Pump Chamber for the South Reservoir is not curbed or gasketed and has a hole in the center to allow that hatch to be removed. Any spill at the South Reservoir building could potentially enter the Pump Chamber and contaminate the treated water in the Reservoir.

• There is no spill containment provided for the chlorine drums at the South Reservoir.

5.3.2 Review of Bacteriological data

The historical bacteriological data from the past five years (2004 -2008) for the distribution system indicates that there has only been one incident where a positive total coliform reading was noted. This occurred on December 27, 2006 at the North Reservoir. The free chlorine concentration in the treated water leaving the North Reservoir on this day was reported as 0.7 mg/L.

5.3.3 Review of Monitoring Programs

The operators monitor the free and total chlorine concentration leaving both the North and South Reservoir on a daily basis. The free chlorine concentration in the distribution system is also monitored on a bi-weekly basis. The historical free chlorine residual data for the past five years (2004-2008) was analyzed. The records indicate that the free chlorine was less than 0.5 mg/L leaving the South Reservoir 161 times, less than 0.5 mg/L leaving the North Reservoir 136 times and less than 0.1 mg/L in the distribution system 14 times. Since the DWSA came into effect on March 1, 2007, there have only been 8 occurrences at the South Reservoir and 29 occurrences at North Reservoir where the free residual entering the distribution system was less than 0.5 mg/L. There have not been any occurrences where the residual has been less than 0.1 mg/L in the distribution system since the DWSA came into effect. Refer to Appendix E for a summary of the chlorine residual monitoring.

While the current monitoring program is in conformance with the DWSA, the current set up makes it difficult to maintain the residual entering the distribution system. This is because of fluctuations of the chlorine residual in the treated water received from the PVWC; dosage is

ASSESSMENT OF WATER SYSTEM INFRASTRUCTURE AND WATER SUPPLY SOURCES FOR THE TOWN OF ALTONA Assessment of the Potential for Microbial, Chemical and Physical Contamination April 1, 2009


modified based on the daily chlorine reading entering the distribution and the large retention time in the Reservoirs.

The operators also take samples of the treated water entering the South Reservoir and leaving both the South and North Reservoir on a biweekly basis. The samples are submitted to ALS Laboratory (formerly Enviro-Test) in Winnipeg for bacteriological testing.

5.3.4 Review of Cross Connection and Backflow Prevention Programs

At the South Reservoir, there is a cross connection between the treated water reservoir fill line and the treated water distribution line. There are two gate valves with a slanting disc check valve separating these lines.

At the North Reservoir there is a cross connection between the treated water reservoir fill line and the treated water distribution line. These lines are separated by butterfly valves.

There is a double backflow preventer installed between the truckfill and Pump Station domestic water line and the distribution header.

5.3.5 Review of Emergency Contingency Plans

The Town’s current operating license requires the Town to submit an emergency response (contingency) plan to the Director by June 1, 2010. In addition to an “Operation/Procedural Manual” that was created in January 2008 the Town has created an emergency measures plan to deal directly with issues concerning the water system.



6.0 Assessment of Physical Works Associated with the Water System

6.1 SUMMARY OF PHYSICAL WORKS

North Reservoir

The North Reservoir was constructed in 1993 and is comprised of a standalone concrete reservoir and Pump Station Building. The top of the reservoir is exposed concrete, while grass covered fill is mounded against the sides. The concrete was not visible due to snow cover, but appeared to have an epoxy protective coating.

The Pump Station consists of a lower level pipe gallery adjacent the concrete Pump Chamber and a main floor to house the distribution pumps, chlorine feed system, emergency generator and Motor Control Centre (MCC). The Pump Station foundation is concrete. The Pump Station building has a steel frame with metal interior and exterior cladding. The concrete and steel building appear in good condition. Minor corrosion is evident on some of the steel water lines.

South Reservoir

The South Reservoir was constructed in 1960 and is comprised of a circular concrete reservoir with internal Pump Chamber / Dry Pit. A small wood frame building was constructed over the Pump Chamber / Dry Pit to house the distribution pumps, chlorine feed system and MCC. The building has metal exterior siding and plywood interior finishing. The building appears in reasonable condition, although the space is tight and there is little room for chemical storage. There is some minor corrosion of the mechanical and electrical equipment, but mechanical items were recently painted.

6.2 ABILITY TO COMPLY WITH REGULATIONS

The compliance of the treated water with regards to the GCDWQ was discussed previously in Section 4. This section focuses on the compliance of the water system with regards to the DWSA and the Ten State Standards.

6.2.1 Drinking Water Safety Act

6.2.1.1 Disinfection and Testing

The water system receives disinfected water from the PVWC and is therefore not required to provide contact time for disinfection. The water system was not compliant with the DWSA in terms of free chlorine level entering the distribution system a total of 29 times since the DWSA came into effect March 1, 2007.

ASSESSMENT OF WATER SYSTEM INFRASTRUCTURE AND WATER SUPPLY SOURCES FOR THE TOWN OF ALTONA Assessment of Physical Works Associated with the Water System April 1, 2009


6.2.1.2 Testing and Record Keeping

The water system was compliant with the DWSA in terms of record keeping in that they record the free chlorine content entering the distribution system on a daily basis and in the distribution on a bi-weekly basis. Bacteriological sampling was also conducted on a biweekly basis, as required by the DWSA.

6.2.1.3 Sampling and Analysis

Bacteriological

The water system was compliant with regards to the bacteriological content in the distribution system between 2004 and 2008, with the exception of one occurrence on December 27, 2007 when a total coliform concentration of 10 MPN/100mL was noted in the water entering the distribution system at the North Reservoir.

Microbiological Standards

The GCDWQ Supporting Document “Protozoa: Giardia and Cryptosporidium” notes that the treatment process in place at the PVWC provides the required three log reduction for Giardia and Cryptosporidium.

Chemical and Radiological Standards

Quarterly sampling of the treated water in the distribution system conducted in 2007 and 2008 indicate that the water system is not compliant with the DWSA TTHM limit of 0.1 mg/L or the BDCM limit of 0.016 mg/L. The remaining chemical and radiological parameters were within the limits noted in the DWSA.

Physical Standards

Annual sampling of the treated water provided to the Altona Public Water System by the PVWC indicates that it is in conformance with the physical standards noted in the DWSA.

6.2.2 Ten State Standards

The Ten State Standards (2007) are to be followed when designing a new water system or when upgrading an existing water system. The following items were noted to not be in conformance with the recommendations provided in the Ten State Standards:

• Currently the chlorine residual is monitored once each day. The Ten State Standards recommends continuous monitoring of the chlorine residual entering the distribution system for water systems servicing more than 3,300 people. Continuous monitoring is also recommended by the DWSA, although is only a requirement for water systems servicing



more than 5,000 people. The DWSA requirement overrides the Ten State Standard requirement in Manitoba and therefore this item is not deemed as nonconforming.

• Spill containment is required to store one spill from the largest container. Currently spill containment is not provided for sodium hypochlorite at the South Reservoir, while spill containment is provided at the North Reservoir via concrete curbing.

• Overflows shall not be connected directly to the wastewater sewer and the overflow shall be designed such that an overflow event is visible. Currently the overflow for both the Reservoir and Pump Chamber at the North Reservoir discharge directly to the wastewater sewer. The overflow for the South Reservoir conforms to Ten State Standards.

• Overflow shall be of sufficient diameter to permit discharge at a rate greater than the filling rate. The overflow for the Pump Chamber at the North Reservoir is a 300ø pipe, while the pipe that fills the reservoir is a 350ø pipe under pressure.

• All reservoir accesses shall include a 100mm high curb with a water tight cover or shall be gasketed and bolted. At the South Reservoir the float valve access hatch is not curbed or gasketed and bolted.

• High and low level reservoir alarming is to be under 24 hour surveillance. Alarming for the water system is externally visual and audible at the North Reservoir only.

6.3 RECOMMENDATIONS FOR IMPROVEMENTS FOR COMPLIANCE

The following recommendations are provided to improve the water systems ability to comply with the DWSA and the Ten State Standards.

• Installation of a chlorine residual analyzer on the distribution header at both the South and North Reservoir would provide continuous monitoring of the chlorine residual entering the distribution system. A chlorine feed pump that would operate based on a continuous feedback loop with the chlorine analyzer to dose additional chlorine as required to maintain a residual greater than 0.5 mg/L entering the distribution would improve the water systems ability to comply with the DWSA.

• While compliance with the DWSA THM and BDCM limit through modifications to the Altona Public Water System, it is recommended to reduce the TTHM and BDCM levels in the treated water supplied from the PVWC. Options include reducing Total Organic Carbon (TOC) in the treated water or investigating alternative disinfection technologies, such as UV disinfection with optimization of the chlorine dose. Further investigation at the PVWC is recommended.

• Spill containment at the South Reservoir is required for the chlorine barrels. A spill deck sized to hold the total volume of one barrel is recommended.



• Installation of two 250ø overflow pipe into the headspace of the North Reservoir and two (2) 300ø overflow pipes into the headspace of the North Reservoir Pump Chamber is required to conform to the Ten State Standards. The overflow pipes shall terminate with a 90°C elbow at least 300mm above the finished grade. A non-corrodible bug and bird screen shall be installed between the elbow and the straight pipe.

• The float valve access hatch at the South Reservoir needs to be sealed or curbed to conform to the Ten State Standards. As the access hatch is required for maintenance of the float valve, it is recommended to curb this hatch. The curb should be a minimum of 100mm in height and hatch shall overlap the framed opening.

• An autodialer programmed to call the operators when a critical alarm is triggered is recommended to comply with the Ten State Standards recommendations for 24 hour monitoring of reservoir levels.



7.0 Summary of Conclusions and Recommendations

The following section summarizes the issues identified throughout the report and provides recommendations for the issues:

1. The sustainability and reliability of the water system is good due to redundant reservoirs, distribution pumping systems, and the emergency generator at the North Reservoir. One item that is concerning in terms of reliability, is the pilot operated float control valve on the Pump Chamber fill line. The operators report that this valve has failed to close in the past resulting in flooding and does not operate when the Reservoir is less than one-third full resulting in inaccessible reservoir space. It is recommended to replace this valve with two electrically operated butterfly valves and to provide a manual bypass valve. The first valve would open and close based on the level in the pump chamber. The second valve would be normally open and would only close if the first valve failed and the Pump Chamber high level alarm was triggered.

2. Maintaining a consistent chlorine residual greater that 0.5 mg/L using manual adjustment is difficult with the current set up due to fluctuations in the chlorine residual in the treated water received from the PVWC. The operators currently increase the chlorine dosed to the reservoir fill line when they observe a low chlorine residual entering the distribution system. As there is approximately two average days of storage at the North Reservoir and one average day of storage at the South Reservoir, it takes one to two days before the increased chlorine dose impacts the residual in the distribution system. It is recommended to install a chlorine residual analyzer on the distribution header at both the South and North Reservoir to provide continuous monitoring of the chlorine residual entering the distribution system. An additional chlorine feed pump is recommended for each reservoir. It would operate based on a continuous feedback loop with the chlorine analyzer and dose additional chlorine as required to maintain a residual greater than 0.5 mg/L entering the distribution system. This would improve the water systems ability to comply with the DWSA.

3. TTHM and BDCM level in the distribution system exceed the DWSA limits. It is recommended to reduce the TTHM and BDCM levels in the treated water received from the PVWC. Options include reducing Total Organic Carbon (TOC) in the treated water or investigate an alternative disinfection technology in combination with optimizing the chlorine dose. Further investigation at the PVWC supply facility is required.

4. The overflows from the North Reservoir and Pump Chamber are not in conformance with the Ten State Standards as they discharge directly to the wastewater sewer. It is recommended to install two (2) 250ø overflow pipe into the headspace of the North Reservoir and two (2) 300ø overflow pipes into the headspace of the North Pump Chamber. The overflow pipes

ASSESSMENT OF WATER SYSTEM INFRASTRUCTURE AND WATER SUPPLY SOURCES FOR THE TOWN OF ALTONA Summary of Conclusions and Recommendations April 1, 2009


shall terminate with a 90°C elbow at least 300mm above the finished grade. A non-corrodible bug and bird screen shall be installed between the elbow and the straight pipe.

5. The float valve access hatch at the South Reservoir is not in conformance with the Ten State Standards and was identified as a potential source of contamination. It is recommended to curb this hatch. The curb should be a minimum of 100mm in height and a hatch should be installed to overlap the framed opening.

6. Spill containment at the South Reservoir is required for the chlorine barrels to conform to the Ten State Standards. A spill deck sized to hold the total volume of one barrel is recommended.

7. The water system is currently monitored by audible and visual alarms only. An autodialer programmed to call the operators when a critical alarm is triggered is recommended to comply with the Ten State Standards recommendations for 24 hour monitoring of reservoir levels.



8.0 Stantec Quality Control

This report, entitled “Assessment of Water System Infrastructure and Water Supply Source for the Town of Altona” was prepared by:

______________________

Jamie Brewster, M.Sc. Process Designer

This report was reviewed by:

Scott Bezak, P. Eng. Project Manager

APPENDIX A

Operating License

APPENDIX B

Operator Certificates

APPENDIX C

Water Quality Data

APPENDIX D

Disinfection By-Product Data

APPENDIX E

Chlorine Data

assessment of water system infrastructure and water supply

Documents