polymeric-based structural rehabilitation of water mains

Polymeric-based Structural Rehab Study

City of Peterborough

POLYMERIC-BASED STRUCTURAL REHABILITATION OF WATER MAINS CASE STUDY City of Peterborough

Peterborough Utilities Commission December 2013

WSI Study report 131209 FINAL.doc

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Acknowledgements This study was undertaken in a partnership among the Peterborough Utilities Commission, ACURO Infrastructure – Rehabilitation, and Caesars Infrastructure Services. We wish to acknowledge the Government of Ontario for funding support received from the Government of Ontario under the Showcasing Water Innovation Program (www.ontario.ca/waterinnovation). Such support does not indicate endorsement by the Government of Ontario of the contents of this material. We wish to express our gratitude to the staff of the Environmental Innovations Branch of the Ontario Ministry of the Environment, the administrators of the SWI Program, for their support, patience and guidance throughout the process. Our gratitude also goes out to Dr. Eric Lanteigne of the Faculty of Engineering, University of Ottawa. Dr. Lanteigne and his graduate students performed the destructive testing necessary to measure the liner thickness of the lined samples, information which was used to confirm the accuracy of a newly developed ultrasound-based liner thickness measuring device. The project team partners also wish to thank Peter Dafoe, Utilities Manager, Greater Napanee Utilities and his staff for their participation serving on our study committee, in critiquing our work, as well as providing their own insight and findings based on similar non-structural lining work they were carrying out simultaneously using this same liner product.

Case Study Steering Committee A steering committee was established to provide guidance on planning and implementing the Project, and also advise on knowledge transfer. The steering committee is composed of members from the Peterborough Utilities Commission, Acuro Infrastructure, Caesars Infrastructure Services, and Greater Napanee Utilities. Greater Napanee is undertaking a similar project under the SWI Program. This collaborative approach allowed the two communities to share information and best management practices. It also leveraged collective expertise and knowledge to optimize Project outcomes to achieve effective problem and issues resolution.


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Table of Content Acknowledgements ......................................................................................................................... 2 Case Study Steering Committee ...................................................................................................... 2 1.0

Project Background ............................................................................................................. 4

2.0

SWI Program Support .......................................................................................................... 5

3.0

Project Objectives................................................................................................................ 5

4.0

Spray-in-Place Structural Lining and the ACURO Lining Technology................................... 6

5.0

Liner Thickness Determination (to ASTM standard) ........................................................... 7

6.0

Liner Thickness Verification ................................................................................................. 7

7.0

The Contractual Work ......................................................................................................... 8

8.0

Study Results and Findings ................................................................................................ 17

9.0

Savings and Advantages .................................................................................................... 18

10.0

Lessons Learned and Areas for Improvement ................................................................... 19

11.0

General Conclusions and Recommendations .................................................................... 21

12.0

Promotional Materials and Presentations ........................................................................ 23

13.0

Appendices ........................................................................................................................ 24


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1.0 Project Background The water infrastructure in Peterborough dates as far back as the early 1900s. As it reaches the end of its useful life, certain water main sections will become structurally deficient and must be replaced or refurbished to extend their life. The Peterborough Utilities Commission (referred to as PUC hereinafter) is responsible for supplying all of Peterborough residents and businesses with safe, clean potable water with sufficient pressure and flow. At this time, the PUC rehabilitates its water infrastructure using cement mortar lining (CML). This technique is employed to improve the water quality but does not provide structural properties to the infrastructure. CML has an estimated useful life of 30+ years. Structural integrity of deteriorated water main is historically addressed through replacement of the pipe. Replacement of pipe is costly, requires the removal and replacement of surface structures (e.g. roads and sidewalks), is disruptive to the public, and is challenging in restrictive work areas. Structural lining is an alternative worth consideration. To repair these water mains, the PUC collaborated with Caesars Infrastructure Services (CIS) to undertake the Project (also known as ”Polymeric-based Structural Rehabilitation of Water Mains”) to pilot test the use of ACURO’s proprietary technology (the Liner) for repairing water mains. CIS and ACURO worked with the PUC to apply the Liner in a portion of the City of Peterborough’s water mains. The polymeric resin is NSF/ANSI 61 certified and exceeds the physical properties required for the ASTM F1216 standard for the rehabilitation of existing pipelines and conduits by the inversion and curing of a resinimpregnated tube. The NSF/ANSI 61 standard establishes minimum health effects requirements for materials, components, products, or systems that come into contact with drinking water, drinking water treatment chemicals, or both. The PUC had the ACURO liner product applied to 150mm water mains on Albertus Ave. and Auburn St. in the City of Peterborough in order to structurally rehabilitate the ailing water mains and eliminate tuberculation from occurring. This innovative technology is also expected to extend the service life of the water mains for another 50-75 years at a reduced cost compared to replacement. Caesar’s Group is comprised of the following divisions: Caesar’s Plumbing and Heating; Caesar’s Environmental Services, Caesar’s Network Services, and Caesar’s Infrastructure Services (CIS). CIS was, at the time the project took WSI Study report 131209 FINAL.doc

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place, the only licensed Acuro Operator/Installer for all of Canada. CIS had exclusive rights for the Ontario market. Acuro is a separate entity that has the licensing and intellectual property rights to the Liner and is responsible for its standards development (ASTM, AWWA). Acuro had granted CIS the rights to apply the polymeric resin technology in Ontario. Acuro worked in partnership with CIS, with CIS having responsibility for carrying out all field installations including all research and development efforts. The Project also validated to a limited degree the use of CIS and Acuro’s new ultrasonic thickness measuring device to measure the liner thickness installed inside the pipe. The device is owned by Acuro and must be field tested by CIS. This device will confirm that the minimum polymeric thickness required for structural integrity of the pipe has been met and that the liner comes in close contact with the host water main. For validation, a section of the liner (called a “coupon”) is cut out and compared to the results obtained by the ultrasonic device. If the ultrasonic device results are validated, the ultrasonic device may be used to measure Liner thickness on the entire length of rehabilitated water mains, not only the coupon sections and without the need to excavate. Secondary benefits of the Project include improved flow and water quality, reduced carbon dioxide emissions compared to replacement, and minimum disruption of traffic to residents and businesses.

2.0 SWI Program Support The project received much appreciated funding support for this new technological initiative from the Government of Ontario’s Showcasing Water Innovation Program. This support made it possible to pilot a new structural lining product for the rehabilitation of water mains possible as well as introduce a prototype ultrasonic liner thickness verification unit.

3.0 Project Objectives The objective of the Project is to showcase innovative, trenchless technologies that will structurally rehabilitate ailing water mains in the City of Peterborough and to serve as a demonstration for other Ontario communities to learn about these two technological advancements.


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4.0 Spray-in-Place Structural Lining and the ACURO Lining Technology The ACURO product is an IC-202 Spray-applied two component NSF/ANSI-61 Certified Polymeric Resin (refer to Appendix 3 for the Product Data Sheet including technical data on the product). The product is proprietary Polyurea blend material. IC-202 is a performance coating that can be utilized to provide structural reinforcement to potable water mains because it is extremely resistant to hydrostatic pressure, corrosion and abrasion. Specially designed equipment was developed for pipeline spraying. The unit must be capable of heating the product up to 82⁰C (180⁰F) and maintain the temperature in heated lines. The plural compound pump used must be piston driven and capable of generating up to 20.7 MPa (3000psi) at a minimum of 9.5 L/min. (2.5 USgpm). The required equipment depends on capturing spray procedures of line speed, spray temperature, and metering of materials during application. Once sprayed inside the pipe the liner product gels in 7 seconds and is tack free within 30 seconds. At this point the next layer can be applied or the pipe can have a camera passed through. The liner, grey in colour, is provided in a number of passes which is determined based on the need for structural or non-structural lining. Structural lining requires more passes and is calculated based on the current condition of the pipe to be lined, in accordance with ASTM1216.


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At 1mm thickness per spray pass, the number of passes applied increases the thickness, which then augments the structural reinforcement of the liner as desired. The liner is anticipated to have a minimum of a 50 year life span.

5.0 Liner Thickness Determination (to ASTM standard) ACURO Infrastructure Rehabilitation determined the internal liner thickness in accordance with ASTM F1216 for 150mm (6”) buried pressure pipe. The calculation is affected by the existing pipe conditions, coating parameters as well as various other calculated data. See Appendix 2 for the calculation sheet. The calculated thickness is to be a minimum of 2.12mm or 0.083 inches.

6.0 Liner Thickness Verification Adequate liner thickness within the rehabilitated water main is to be confirmed through measurement in-situ using the ultrasonic unit prototype which was developed specifically to measure the liner thickness in-situ. For this pilot project the unit was to confirm minimum liner thickness every metre or thereabouts. Furthermore, for the particular study, samples of the lined pipe will be cut out of the water main and sent to an independent party to actually remove the liner and measure the thickness. As noted above, the calculated minimum required liner thickness is 2.12mm. The independent party that measured the liner thickness was Dr. Eric Lanteigne, Department of Mechanical Engineering, University of Ottawa, with the assistance of some of his senior students. Even though the liner sets in about 7 seconds, it is in a liquid state during spraying so it is pulled by gravity towards the bottom of the pipe. For that reason, liner thickness measurements are taken at the top of the pipe where the liner thickness would be the thinnest. It is that measurement which must meet the minimum thickness requirement.


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7.0 The Contractual Work 7.1

The Work Sites

The water mains within two streets of the city – Abertus Ave. and Auburn St. – were structurally lined using the ACURO product. The Albertus Ave. water main, 150mm cast iron installed in 1950, had experienced 11 documented water main breaks over the 310 metre length and was in a fairly restricted workspace – a narrow street with other existing buried and above ground utilities to accommodate. The Auburn St. water main, 150mm cast iron installed in 1930 & 1952, had experienced nine (9) documented water main breaks in the past over its 325 metre length.

ALBERTUS AVE. VIEW

7.2

AUBURN ST. VIEW

Work Site Preparations

Arrangements with the City of Peterborough had to be made for road and lane closures where required and plan traffic routing during the stages of construction, and slug discharge for pipe cleaning water, flushing water and shock-chlorinated water prior to putting the water main back in service. PUC staff had to go around and confirm that all the water main valves and the service curb stop valves were operational, and repair/replace them if they failed to operate properly. Otherwise, the lining would either blister or fail to bond to the pipe wall if water were permitted to leak back through a WSI Study report 131209 FINAL.doc

Water main before rehabilitation 8

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faulty valve into the pipe to be lined. Installation of a temporary water main and services to all customers was required, connected to the hose bibs during the period that the water main was shut down. All the customer’s curb stops had to be shut off first as noted above. Note that future consideration could be given to only shutting the water main down for two one-day shutdowns – cleaning one day and lining the second, once the process is refined and the contractor better experienced. No temporary water main would be required, reducing the cost of this technique by approximately 30%. Project notification went to affected customers on the streets to be lined as well as neighbouring customers affected by the shutdown of a section of water main.


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Albertus Avenue Plan


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Auburn Street Plan


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Excavations of access pits, approximately every 150m, were made above the water main to be lined, as well as at intersections. The pits were approximately 2.5 m x 2.5 m x 2m deep and shored for safety. The pits were required to access the water main for cleaning and for lining the water main. 7.3

Water Main Cleaning and Drying

Prior to lining the water main, the contractor has to open up the pipe by cutting out a section of water main approximately 2 m – 3 m long in each of the pits in order to clean the pipe. Cleaning is required to remove obstructions such as solids and solidified deposits, oil, grease, prior coatings such as bitumen or other coatings that will prevent the application of the liner and bonding of the liner to the pipe. The pipes, considering these two streets had cast iron pipes that are 1950’s vintage water mains, were in poor condition having significant tuberculation internally due to internal corrosion. Various cleaning methods were tried – scraping/brushing the water main; highpressure water application (by Exotec), and blowing stone (Envirologics’ Tomahawk process) through the pipe. Once the cleaning was complete and verified by CCTV video inspection using a self-driven camera unit, the pipe was air dried by pumping air through the water main. The success of the drying was confirmed by further video inspection.

Water main after cleaning

7.4

Water Main Spray-on Lining Application Once the pipe has been confirmed by video inspection as dry and clean, the application of the liner commenced. The liner is applied by first pulling a spray head hose through the pipe from one pit to another. The robotic spray head is then attached to the Insertion of the spray gun end of the hose and pulled back through the and start of spray pipe, spray-forming to the original pipe. The application polymeric resin is a thermoset material, cure-applied using impingement mixing of two components under hydraulic pressure within the hose. WSI Study report 131209 FINAL.doc

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Following the first pass the spray process is repeated enough times to obtain the necessary thickness required to meet the structural lining criteria as per ASTM F1617. The fast-set nature of the polymeric resin (gels in 7 seconds, tack free in 30secs) allows further applications to occur immediately after each application. Each pass applies an average wall thickness of 1mm. Therefore, to obtain the calculated minimum wall thickness of 2.12mm for this project three passes were required. The contractor actually applied 3 or 4 passes recognizing that even though the gel time is short the material will to some degree migrate to the bottom of the pipe due to gravity. The thickness is computer controlled by the spray rig software, which controls the polymericresin feed rate as well as the rate that the sprayer moves through the pipe. The spray rig software produces a printed record of volume of resin applied, hence the average lining thickness. The post lining video validates proper installation.

Liner after spray application

In some cases a customer’s water service may be plugged or partially plugged. Once the liner has set, a remote-controlled robotic cutter can be used to drill and reinstate a service (although this was not required on this project since the services were not plugged and the liner protected the service). Service locations are marked as part of the video inspection after pipe cleaning, although most services tend to be visible after spray application. Water Service after Lining

Following pipe lining, the wall thickness is verified and a video inspection undertaken of the lining. The removed sections of pipe in the access pits that allowed access to the main are then replaced with a new section of pipe. The newly lined pipe is then disinfected in accordance with AWWA standards, flushed, and then water quality tested to ensure it is safe (chlorine residual, turbidity, and bacteriological testing). The water main is placed back into service WSI Study report 131209 FINAL.doc

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and the site restored, which includes road restoration, sidewalk replacement and sod or seeding of grassed areas.

7.5

Liner Performance and Measurements

The anticipated results of structurally lining the water main are to: Obtain an interior pipe coating that will compensate for the deteriorated condition of the cast iron water main eliminating further interior corrosion and hence extending its service life. Obtain a smooth- walled coating and restored interior pipe diameter through the removal of internal build up (rust carbuncles) and lining application thereafter that will improve flow conditions and water quality. Achieve structural renewal through adequate liner thickness based on the liner material being used and the state of the deteriorated pipe. Obtain a liner that is free of layer splitting or wall/liner separation. Once the water main had been lined, a 300mm – 450mm sample was cut out from each water main. Due to the destructive nature of extracting a lined section of water main, only one sample from each street was taken. Cutting out a section introduces two more points of potential failure which compromises the integrity of the pipe. For this project we were able to obtain one of the samples where a new isolation valve was being installed anyway. The sample liner thicknesses were first measured using the new ultrasound measuring device by Caesar’s Infrastructure at their facility in Ottawa. The original intent was to measure the liner thickness on site along the entire length at one metre intervals on each street. The unit, a newly developed prototype broke down during the first attempt on measuring in-situ on Albertus St. Failed parts had to be ordered from Australia after which the person skilled in its operation had to leave the country. Therefore extracted samples had to be measured in Ottawa. This reduced the pipe length of measurement readings for wall thickness confirmation from 700 m (based on 1 m intervals on site) to two cut out sections totalling 580mm, in addition toreadings of 17m of pipe length taken on Albertus prior to the unit breaking down. The ultrasonic unit results were verified by actual measurements of the liner by Dr. Eric Lanteigne of the Department of Mechanical Engineering at the University of Ottawa. Liner thickness was confirmed at the 10 o’clock, 12 o’clock (top of pipe) and 2 o’clock positions where the liner would be the thinnest. A copy of his WSI Study report 131209 FINAL.doc

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report is appended (Appendix 1). In summary, the ultrasonic readings versus physical measurement in Ottawa were as follows: Sample 1 – Albertus Ave.

Min

Max

Average

mm/in.

mm/in.

mm/in.

Ultrasonic

2.44/0.096

2.83/0.111

2.63/0.104

2.12/0.083

Physical

2.03/0.080

2.59/0.102

2.12/0.083

Variance %

+20%

+2%

Physical at 12 o’clock

1.75/0.069

2.34/0.092

Sample 2 – Auburn St.

Design Thickness mm/in.

Min

Max

Average

Design Thickness mm/in.

mm/in.

mm/in.

mm/in.

Ultrasonic

2.67/0.105

2.86/0.112

2.79/0.110

2.12/0.083

Physical

2.21/.087

2.77/0.109

2.12/0.083

Variance %

+21%

+0.7%

Physical at 12 o’clock

1.98/0.078

2.64/0.104

From the above results the conclusions are that: On average the minimum thickness of 2.12 mm (0.083”) was likely obtained based on the ultrasonic measurements as well as physical measurements obtained from the University of Ottawa lab results. The liner failed to obtain a minimum liner thickness in some locations at the 12 o’clock position of the pipe, the interior top of the pipe being the area receiving thinner coverage due to gravitational pull on the sprayed product. The ultrasonic unit, based on very limited comparison testing, on average appears to provide wall thickness readings slightly greater than actual wall thickness (2% and 0.7%) and significantly higher for the minimum thickness readings (20%). WSI Study report 131209 FINAL.doc

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Due to failure of the ultrasonic unit during construction, adequate data could not be collected to better verify the accuracy of the ultrasonic unit. More testing and calibration of the ultrasonic unit is required in the future. The application process of the polymeric resin needs to be refined or additional passes are required to ensure that the minimum thickness is achieved along the entire length and interior circumference/surface of the pipe. 7.6

Disinfection, Water Sampling and Service Restoration

Upon completion of the lining of the water main, the main is flushed using the municipal distribution system to remove any debris. Following flushing, the newly lined main is superchlorinated for 24 hours using continuous feed method with a chlorine solution that maintains a concentration between 75mg/L and 300mg/L (note that this has been reduced in 2013 to a range of 25mg/L to 200mg/L in line with AWWA Standard 651). After chlorination, the main is flushed to clear the main of the super-chlorinated water. Water used for flushing is discharged to the municipal sanitary system. Flushing continues until the free chlorine residual is less than 1.5mg/L and the turbidity is less than 1.0 NTU. Bacteriological sampling and testing is undertaken on the main, every 200m or less, once the main has been flushed and the free chlorine residual and turbidity levels have been achieved. Bacteriological testing includes testing for total coliform, E-coli, Background Count, and Heterotrophic Plate Count (HPC). Three consecutive samples were taken at least 24 hours apart, all which met the criteria noted below. Note that for Day 1 of the 3 days of testing, free chlorine residual and turbidity is measured in addition to the bacteriological measurements. The following criteria must be met: Free chlorine must exceed 0.20mg/L Total chlorine must not exceed 1.5mg/L Turbidity must be less than or equal to1.0 NTU Total coliform must be ‘Not Detectable’ (O. Reg. 169/03) E-coli must be ‘Not Detectable’ (O. Reg. 169/03) Background must be less than 200 CFU/100ml WSI Study report 131209 FINAL.doc

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HPC must be less than 500 CFU/1ml The main can be placed back into operation once the testing passes. Service is restored by opening the curb stops and the temporary water main can be dismantled. It should be noted that to facilitate return to service conditions, other methods for disinfection could be used to reduce the disinfection period. However, these methods were not a consideration for this pilot project..

8.0 Study Results and Findings The characteristics used to evaluate the success of the project include hydraulics impact; water quality; aesthetic impact, liner thickness findings, and pipe life expectancy. The purpose of the PUC structural lining of the municipal water main is to both extend the life of the water main while increasing resistance to internal pressures and external loads (hence the structural component of lining) and to improve the water quality and flow characteristics (hence lining the water main). The liner thickness verification at the University of Ottawa indicates that: 1. the ultrasonic unit, or the interpretation of the ultrasonic readings, over-estimates (ranging from 0.7 to 21%) the actual liner thickness and therefore needs calibration or refined interpretation 2. generally the minimum thickness of liner has been achieved throughout with some exceptions for readings at 12:00 (top of the pipe) From this study we believe that with the polymeric resin lining we have a water main that is structurally more sound, which will reduce the potential for leakage and breakage, and therefore will last longer, theoretically some 50 years. Flow has improved due to the increased diameter that resulted from eliminating tuberculation. Fully expect that water quality is improved since the iron tuberculation has been eliminated permanently in these two sections of water main. Due to the limited extent of this pilot project,(only 635meters of 150mm cast iron water main rehabilitated), the improvement would not be detectable. WSI Study report 131209 FINAL.doc

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Chlorine demand reduced due to elimination of the tuberculation. However with only two mains restored, the reduction would not be detectable. When considering that some 150km or so will be lined to eliminate tuberculation the demand will be significant. To date the Utility has lined approximately 121km and replaced some 40km, of a system currently composed of some 415km. Over that same period the chlorine use in mg/L has been reduced by 74%. Therefore a portion of this reduction can be attributed to lining (primarily cement mortar lined, with some polymericresin lining in the past) and replacement of water main with PVC water main. Napanee has undertaken studies in 2011 of water main lined with the Acuro product and their findings indicate that the fire hydrant flows increased anywhere from 110% to 680%. Furthermore, lining eliminated low chlorine residuals at dead ends, increasing residuals from around .35ppm to 1.25ppm, and reduced/eliminated rusty water complaints. PUC’s own limited flow testing indicates that on Auburn St., fire hydrant flows increased by approximately 200%. However, on Albertus the limited historical flow test results infer that that fire hydrant flow has experienced no significant increase, likely due to the similar corroded pipe in the area yet to be lined. The polymeric liner forms a very smooth, hard plastic-like surface which aids flow and deters buildup within the pipe. The ultrasonic unit broke down after completing some 17metres of the first section of water main that was lined. Parts had to be ordered from Australia which was expected to take some 2 weeks. By the time the parts came in the sole person skilled at running the unit had left the country.

9.0 Savings and Advantages Capital Cost Savings: The alternative to structurally lining a water main is to replace the water main. Replacing a water main on either of these two streets would cost in the order of $800.00 per metre. The average actual cost of structurally lining these two streets was $662 per metre. This results in a savings of $138 per metre, or a total savings of $94,800. Deferred Replacement: This rehabilitation method is anticipated to extend the service life of the two water mains by approximately 50 years. WSI Study report 131209 FINAL.doc

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Water Break Repair Savings: Albertus has experienced 11 breaks over the past 50 years with an average break rate of 0.64 breaks/km/year. Auburn has experienced 9 breaks in the past 50 years with an average break rate of 1.1 breaks/km/yr. Based on a repair cost of $10,000 per break, the cost savings for the two streets amounts to $5,900 per year. The significant reduction in water main breaks will reduce customer service interruption and the dirty or rusty water complaints relating to system start up. The use of an ultrasonic device will confirm on site right after the liner application whether the desired liner thickness along the entire length has been achieved. Additional liner application can then be done immediately following if required. Previously the only means to confirm liner thickness was through destructive testing by digging a pit, cutting out a sample and measuring the exposed liner thickness.

10.0 Lessons Learned and Areas for Improvement The lining of water mains using the polymeric-based resin is a fairly new technology, although the product itself has been used in many other applications for many years. The greatest challenge faced by this technology isn’t so much the product but is the application of the product and more so the ancillary works relating to the application, such as cleaning the water main. The following are a number of issues encountered during this pilot project. Cleaning Technique: The water main cleaning technique needs to be determined and identified in advance. Three techniques (water, air, and/or stone media) were used, partly for different pipe conditions encountered but also involved trying new cleaning methods. There is a need to develop pipe cleaning procedures for types and conditions of pipes encountered. Also, possibly further field and lab testing of the pipe cleaning techniques. Action by: Envirologics/ACURO Stone cleaning method – issue with stones being blasted into tees, hydrant leads, services or just sitting in the pipe; need a means of ensuring all stone is removed such as blow back on services and on the main before lining...need a protocol Action by: Envirologics Note that Napanee used water jetting and also the stone blasting method to clean the pipe and remove the bitumen coating. Access to Buildings/Homes: Access could be required to turn off or on the main water service shutoff or to provide an outside water tap where there was none for the temporary water service. Major problem noted by WSI Study report 131209 FINAL.doc

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Napanee was the access to customers’ homes – too many times having to get into homes/buildings –often hard to find people at home; customers frustrated with being bothered so often, but more importantly there was no protocol as to when and why access was needed. Action by: CSI: develop a protocol for building access – when in the process, why, who, blowing lines out, drop water meters Plugged Water Meters: Plugged water meters due to some cleaning processes (grit or stone), also other equipment in the house such as a refrigerator water dispenser. It was noted that in the Cambridge project all the water meters were removed prior to cleaning. Action by: CIS/Envirologics - part of the protocol for building access Humidity: Humidity in the pipe was an issue creating blistering in the liner. Blowing of cool air apparently has eliminated this problem. Equipment reliability: During these projects equipment broke down – e.g. ultrasonic unit breaking down almost right away and out of service for the rest of project (broke down and no one to operate it thereafter since this was a new unit under development; no off the shelf replacement available); the liner gun failed – significantly reduces productivity, delays the project, increases the cost, or in the case of the ultrasonic unit was not able to confirm on-site the validity of this new piece of equipment which is meant to confirm liner thickness. Action by: CIS/application contractor needs to have key equipment and replacement components readily available. Radical liner thickness at ends: Noted that the liner spray can be radical near the end of the pipe (such as stalagmites forming in one section of Auburn St, Peterborough. Peter Dafoe, Napanee Utilities, suggested placing a temporary extension to the pipe during spraying. This may require the pits to be larger. Action by: CIS/ACURO to look into possible solutions. Pit Numbers and Size: Unforeseen by the PUC, required for lining and for stone blasting cleaning procedures , the number of pits and the size of the pits are significantly increased in comparison to cement mortar lining of water main, leading to restoration cost increases and roads with more patching. In Napanee’s experiences, pits were limited to about 110m, noting there were also situations that required these shorter runs. PUC noted that pits were approx. 50% bigger than CML pits. Action by: CIS/Envirologics – look into whether pits can be smaller dimensionally and if longer runs can be lined. (Noted that hose is 500 ft but spray gets disrupted on longer runs due to simultaneous air spray when improperly managed). WSI Study report 131209 FINAL.doc

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A protocol/practice needs to be outlined from first day through to cleanup – regarding such processes as pit location selection, pipe cleaning technique selection and related process, customer information and building access expectations and processes, stone removal from tees, services etc., equipment requirements and equipment failure protocols. Action by: CIS – develop protocol On-site communications failure – i.e. between CIS and their subcontractor, as well as between all the other involved parties. Need to have just one contractor contact on site. Action by: CIS – develop protocol Pipe cleaning – Because of the existing bitumen coating that had to be removed, new cleaning techniques were developed. It was noted that in Peterborough on Auburn St at least, the water main was cleaned using a specially fabricated nozzle that rotates around and in very close proximity to the pipe wall using low pressure water. This method was used since the stone blasting technique alone did not completely remove the bitumen coating at the time. After cleaning and removal of the bitumen coating, the blast stone method was used mostly to dry the pipe. Peter Dafoe, Napanee Utilities, suggests that possibly removing most of the build-up inside the pipe could be accomplished with first using the scraper technique, used in CML projects, before stone blasting – this was success in a past year’s trial of this product. Select cleaning process(es) depending on condition of the pipe and type of coating to be removed. Action by: CIS/ACURO Field Operations: Field operations were very inefficient with jobs taking much longer than estimated by CIS, due in most part to contractor being unfamiliar with the requirements of the work other than cleaning and spraying of the pipe, learning ways to properly clean and dry the pipe, and equipment failure. It is noted that this was a pilot project and therefore many aspects relating the application of this new material was a learning experience for CIS. Action by: CIS, to apply the knowledge and experience gained on this pilot project to improve their performance on future projects.

11.0 General Conclusions and Recommendations 1. It is concluded that the polymeric-based liner product provides a practical solution to structurally enhance deteriorated cast and ductile water mains while at the same time eliminating tuberculation, and the water quality and WSI Study report 131209 FINAL.doc

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flow issues resulting from tuberculation. It is also an alternative solution where long term interruption required by water main replacement of local activities cannot be tolerated, such as on a busy commercial street. The use of this product for this purpose is therefore recommended. 2. The ultrasonic unit broke down on the first run on site on Albertus Ave. after only completing 17m of water main. This is a critical component to confirm that the liner of adequate thickness to provide the structural strength required. It is recommended that the unit’s reliability needs to be greatly improved with a backup unit and key spare parts available. 3. Once the ultrasonic unit was repaired the person skilled at its operation and results interpretation was no longer available. It is recommended that the contractor have adequate skilled resources to ensure the ultrasonic component of lining can be undertaken and unit repairs completed on site. 4. It is recommended that the ultrasonic unit be calibrated assuming the interpretation are correct and undergo further field testing prior to using the device to confirm liner thickness. 5. It is recommended that the contractor(s) licensed to structurally line water main with the ACURO product be better trained in the application andthe work required before and after lining to improve efficiency and reduce time required to line and put back into service a water main. 6. The water main needs to be cleaned and dried prior to lining. Various water main cleaning techniques were tried prior to lining a water main. Bitumen on the interior of the water main created additional challenge to cleaning the pipe in the case of Peterborough’s water main. It is recommended that cleaning and drying techniques be further investigated, refined, selected based on the water main encountered, and develop a protocol for an operator on site to reference. Overall, the product is worthy of consideration as a means of structurally enhancing a water main, avoiding replacing a water main, or simply as a means of improving water characteristics such as flow and water quality. However the application process and the ultrasonic unit need significant, but not insurmountable, improvements.


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12.0 Promotional Materials and Presentations The following is a list of promotional materials and presentations regarding this pilot project utilizing the ACURO lining product. 1. A ‘Project Overview’ video prepared by ACURO Infrastructure; reviewed by PUSI. 2. A Single page handout – Peterborough Utilities Services – Water Main Structural Lining Pilot Project; prepared by ACURO Infrastructure and handed out at trade shows attended by ACURO Infrastructure; reviewed by PUSI. 3. A Powerpoint presentation entitled: ‘Cutting Edge Advancements: Water Main Renewal using Spray‐on Polymeric Resin’, prepared and presented by ACURO Infrastructure at the Underground Infrastructure Research International Conference and Trenchless Technology Road Show held in Niagara Falls June 5 -6, 2013. It included a short video of lining projects being undertaken. 4. This pilot project was mentioned in a Powerpoint presentation entitled “A New Watermain Cleaning and Lining Preparation Process” by Envirologics (a subcontractor on this pilot project) at the CATT Workshop on Pilot Projects: Lessons Learned; dated January 24, 2013. 5. Other Promotions – ACURO Infrastructure had a trade show booth at the annual Eastern Ontario Water Works Conference held in Trenton, Ontario on Oct. 23/24, 2012. As well ACURO presented at the trenchless technologies conference noted above. 6. This report once finalized, which will be available on the Peterborough Utilities’ website.


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13.0 Appendices 1. Technical Report: Produitson Ultrasonic Module Polymer Thickness Verification; by Dr. Eric Lanteigne, Department of Mechanical Engineering, University of Ottawa; December 2012. 2. Internal Liner Thickness determination for structural lining of Peterborough Utilities water mains; by ACURO Infrastructure, May 08, 2012. 3. ACURO product data sheet – IC-202 Spray-Applied Lining 4. Structural Lining of Mains – anticipated cost savings backup info. (single page) 5. Email, An Understanding of Structural Lining, from ACURO to PUC, May 29, 2012 6. Table & chart of Chlorine Demand as a result in part of Watermain Replacement


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APPENDIX 1 - Technical report by the University of Ottawa


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The above results are from the ultrasonic unit inspection of the liner thickness on Albertus Ave. which was the first use of the new unit. The unit broke down during this inspection and could not be repaired prior to the completion of either Albertus Ave. or Auburn St.


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______________________________________________________________________________ Report Author’s Note (Dec. 09, 2013): The above results are from Caesar’s subjecting the two cut out samples of lined water main to the ultrasound unit. Note that apparently only a single measurement was taken in each sample at the 10, 12 and 2 positions whereas lab testing at the University of Ottawa took several thickness measurements along the full length of each water main sample. _____________________________________________________________________________


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APPENDIX 2 - Internal Liner Thickness Determination for structural lining of Peterborough Utilities water mains; by ACURO Infrastructure, May 08, 2012.


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APPENDIX 3 - ACURO Product Data Sheet – IC-202 SprayApplied Lining (pg. 1 of 3)


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ACURO product data sheet – IC-202 Spray-Applied Lining (pg. 2 of 3)


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ACURO product data sheet – IC-202 Spray-Applied Lining (pg. 3 of 3)


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APPENDIX 4 - Structural Lining of Mains: Anticipated Cost Savings info


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APPENDIX 5 – “An Understanding of Structural Lining” email


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APPENDIX 6


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