Monday, September 26, 2022

Connecting first nations communities to the network

With latest reports of declining CIPP liner quality, German testing institute Siebert + Knipschild warns of excessive pessimism

With latest reports of declining CIPP liner quality, German testing institute Siebert + Knipschild warns of excessive pessimism. Based on 6,000 samples out of three European countries in one year, the inspection engineers concluded that more installation companies than ever fulfilled the requirements for successful CIPP sewer renovation, rewarded by the Seal of quality. Instead of complaining about a perceived decrease in quality, Siebert’s managing director is asking everyone to instead consider the question ‘What makes a good CIPP product?’

“Much more than just the source CIPP product, it is the combination of multiple factors including a sensible call for bids, a made-to- measure liner and a successful installation and curing procedure that add up to a final judgment of any given contractor’s work.” said Andreas Haacker, managing director at Siebert + Knipschild, one of Germany’s leading institutes for testing CIPP materials. Quality of the process in particular correlates with a contractor’s experience with a system, the equipment as well as personal qualification.

Further influencing the final judgement is the sense of “next- gen” sustainability, both regarding climate protection as well as the longevity and durability of the CIPP liner. “In short, it is all about having a PLAN. Planning, Liner quality, its Application and Next-gen sustainability all need to be up to par.” said Haacker. “Whether you are a client, a contractor, or a manufacturer, each of them is equally key to success.”

- Advertisement -

Liner-only rankings are ‘like Formula One without a driver’

What liner yielded the best results? This question is flawed in the eyes of Andreas Haacker. “We purposefully do not rank the liner manufacturers in our scorings without looking at the contractors’ work. This would warp the results. Imagine ranking only the race cars in Formula One, completely ignoring the skill in piloting the vehicles. We look at the full picture instead.” he said.

Another point on the chemical engineer’s mind was that there is a risky tendency among communal decision makers to minimise prices and maximise pipe diameters at any cost. He said: “It is generally more successful to carefully consider the curing process and adjust the timeframe with regards to the general conditions. Process technology plays a decisive role here. It should be noted that contractors work with different systems regarding their UV curing equipment. This is not always taken into account within the DIBt’s qualifying admissions.” If no references or previous experiences are available, Haacker recommends ordering residual styrene analyses to assess the successful curing of the entire wall thickness.

Wall Thickness Specifications

One aspect that may lead to confusion is a perceived wall thickness discrepancy between a sample and the product information sheet. Nothing to worry about, said Haacker: “Usually the reason for this is quite banal. Wall thickness specifications in the manufacturer information are not unified. For the test and the static consideration, the wall thickness of the supporting laminate structure is decisive as a reference value, because this already includes the reaction shrinkage. If we receive a sample like that, we usually just ask to clear up this misunderstanding.”

As chairman of the board of the pipeline rehabilitation association (RSV), Haacker advocates for a standardised way to note wall thickness to prevent confusion on the construction sites.

Siebert + Knipschild bases its seal statistics on around 6,000 datasets from Germany, the Netherlands and Austria.

Never before have so many contractors been awarded with the seal as this year. “Exceptional standards of quality in every area are becoming more essential for companies. We are seeing an increased effort from contractors to not only fulfil requirements, but also to give clients the safety of a durable and sustainable product for the next generations.” he said. A CIPP liner’s depreciation period is usually around fifty years, however, the expected life cycle is much longer than that, according to Haacker.

In the same vein, house connection systems have high requirements for CIPP liners, appearing multiple times in this year’s seal statistic. “The companies in this field are increasingly using the seal to build up trust for the systems.” explained Haacker.

Among the 26 contractors honoured with the seal, some hail from countries outside of Germany such as Austria and the Netherlands. “We are seeing growing interest in the seal from companies both domestic and foreign.” As such, English-language application documents and information are available for download on the Siebert + Knipschild website.

Quality Data on Demand

According to Haacker, the seal is a good reference for successful projects – for both clients and contractors. To be eligible, a minimum of twenty samples per system must be provided in the previous calendar year. The testing institute inspects the wall thickness, e-module, bending strength and watertightness. Some 95 % of samples must pass the requirements to be eligible for a seal. The testing will examine components sent from the contractors as well as the clients of the individual projects. They must be from four or more different construction measures.

All in all, the seal is a good opportunity for clients to get an overview over which companies deliver good quality. Contractors benefit from a recognition of their consistently high-quality work as well. Another perk seeing increased recognition from the companies. Those ordering the seal will receive a certified statistic over a year. “Companies will use the yearly data for their internal quality assurance. We can provide this data on demand” noted Haacker.

Preparations for the seal award 2022 are already underway. German- and English-language application materials and a detailed checklist of the criteria can be found on the Siebert + Knipschild website at siebert-testing.de/en/seal-of-quality/. For projects where the public sewer network operator has initiated the inspection, a declaration of consent is required and available for download as a template as well.

For residents in the Wauzhushk Onigum and Obashkaandagaang First Nations, clean, safe drinking water from the tap is a luxury they had not had access to in nearly a decade.

Located near Kenora, a small city situated on the Lake of the Woods in north western Ontario, Canada, about 124 miles (200 km) east of Winnipeg, both of these communities had been under water-boil advisories since 2012. With funding provided by Indigenous Services Canada (ISC) and the federal government, a project to connect the First Nations’ water and sewer infrastructure to the City of Kenora’s municipal water system was designed to greatly improve the communities’ poor water situation.

The full scope of the project included a new water treatment plant with treatment and disinfection equipment, a below-grade concrete water reservoir under the building, a generator set for backup power, a parking area around the building, electricity and communication lines to the building, a septic field for wastewater, a 246 ft (75 m) long water intake pipe and a 311 ft (95 m) backwash outfall pipe into Lake of the Woods, multiple distribution pumps, and 3,822 ft (1,165 m) of watermain piping. Completed, the new facility was designed to eliminate two long-term water advisories and restore fresh drinking water to the two communities.

To install the water pipes from Kenora to Lake of the Woods, the city’s sewer and water department contracted Staal Irrigation & Contracting of Rosslyn, Ontario, for the horizontal directional drilling (HDD) work. Using a Vermeer D40x55DR 3 Navigator® HDD to complete the boring, owner Ian Staal and his crew were able to get their part of the project done in less than seven weeks. “It was quite the project, not your run-of-the-mill drill shot into a lake, that is for sure.” said Staal.

DRILLING TO THE LAKE

The project called for the Staal crew to install two pipelines of Schedule 11, HDPE pipe on the Kenora side of the lake. One was 18 in (457 mm) diameter and the other was 16 in (406 mm) diameter. For both pipes, the crew bored a 24 in (609 mm) diameter hole. From where the drill was positioned on shore, each bore was approximately 370 ft (112 m) in length.

Staal said the combination of a Mincon air hammer and INSTA-VIS foam drilling fluid was ideal for tackling the rocky soil conditions for the 51⁄4 in (133 mm) diameter pilot bore. Powering the Mincon tool was a 1,600 cfm (45.3 m3/min) air compressor running at 375 psi (2.6 MPa). With this combination of equipment and pressure, Staal said it was all about getting the bore hole right the first time. “You cannot push it, you cannot rush it. You just have to be very methodical and think of every single move because you cannot redo your bore.” he said. “Because we were in rock, we really had to pre-plan every single inch, every foot and every percent.”

On the way back through the hole, the crew used a Vermeer reamer to expand hole to 12 in (304 mm) diameter. Using the same reamer, but with a different carbide tip on the front end, the crews continued to go back through the bore path, lapping and spinning to make the holes increase from 12 in to 24 in (304 mm to 609 mm). Throughout the bores, the crews used a DigiTrak® Falcon® F5® locating system to track their progress.

“Every time we needed to make a tool change, we had to do it on the lake. On the first bore, we rented a barge with a big crane and used that to help us push out additional rods, giving us more flexibility. Then we would go down, chain on the end of the pipe and crane it out. As the person on the drill would push up more rod from shore, the crane would give us more leverage and allow the pipe to come up easier.” said Staal.

He went on: “Then, we would get the pipe up on the edge of the barge, still connected to the drill, ratchet it all down on the deck of the barge, then lower the drillhead reamer down into the lake and pull it back.” Staal added: “It was a bit of a process, so on the second one, instead of using the barge, we used divers.”

FACING CHALLENGING CONDITIONS

One challenge Staal’s crew encountered during the bores was the ground conditions changing unexpectedly on the lakebed. “It was supposed to be all bedrock. The problem was that about 200 ft (60.9 m) out on the beach shore, there was a section that went from rock to native soil and then went back into rock.” said Staal. “Using that much pressure there and trying to hammer through, and then abruptly finding out that it is not all rock, was really surprising, we were probably at a depth of 20 ft (6.09 m) when we hit the dirt pocket.”

To alleviate the situation, Staal’s crews used fluted reamers with clay cutters on the end of their D40x55DR S3 to clean out the drill hole.

Staal estimated that his crews bored out around 60 ft (18.2 m) from shore and emerged in about 10 ft (3.04 m) of water. Since the crews were going through differing ground conditions,

Staal said that their drilling averages varied widely. “Sometimes we were able to go 10 ft (3.04 m), which is one rod in about 35 to 40 minutes. Other times, it would take 90 minutes or more to do the same amount of work.”

Staal noted that it can be stressful but being patient is the best way to work through these types of challenges. “You have to just be persistent and take your time. I mean, we just let the air and the bit do the work, which meant that sometimes we were sitting there on the drill and going slowly. That is the best way to get the job done right.”

CONNECTING TO THE OTHER SIDE

According to Staal, at the same time his crew was doing the HDD work on the Kenora side, another contractor was doing all the sewer and water lines on the reserve side. That contractor used breakers and vertical drilling to blast the bedrock, then dug the material out of the way and trenched the pipe in.

Once the HDD bores to the lake were completed on the Kenora side, and the trenching done on the reserve side, the project specs called for the two new pipes to be installed on the lakebed a little over 9 ft (3 m) apart. “The timing worked out really well.” said Staal. “While we worked on our bores, the other contractor was finishing the work on the reserve side. We finished up on both sides of the lake at about the same time and were ready to pressure test, set it up and tie it all in together.”

The pipe was welded together on the reserve side, and then the pipe, filled with air so it would float, was pulled into place with several boats. Divers connected the pipe to the end of the drill string above the ‘daylight hole’ (bore exit point on the lakebed), and Staal’s crew and their Vermeer D40x55DR S3 drill took it from there.

“When we brought the pipe to shore, we pumped water from our vac truck into the line to act as a counterweight and get the line to lay down in the water so we would have a better entry angle.” explained Staal.

Once the pipe was pulled into position and connected on both shorelines, the two lines were anchored to the bottom of the lake using concrete weights.

For the Staal team, this Lake of the Woods water and sewer project was just another example of how far the company has come in the past decade when they only installed sprinkler systems. Since then, Staal Irrigation & Contracting has expanded to five HDD crews with five Vermeer HDDs and several vacuum excavators.

The Lake of the Woods project was one of the first times the crew has operated a Mincon air hammer, but Staal said the team at Vermeer Canada and Mincon supported them every step of the way. “We really appreciate all the time those folks spent with our guys on this job. They were every bit as invested in seeing us be successful on this project as we were, and that means a lot to all of us.” he concluded.

- Advertisement -
Newsdesk
Newsdesk
Trenchless Works bringing you balanced journalism, accuracy, news and features for all involved in the business of trenchless and no-dig from around the world

Related Articles

- Advertisement -
- Advertisement -
- Advertisement -