But weather conditions haven’t stopped Darwin from installing a 1 km-long sewer pipeline. According to Trenchless Australasia  online, the pipeline, which was created using micro tunneling techniques “cross[ed] under Darwin’s Stuart Highway, then negotiated through multi-story residential  [and tourist] areas” to join the city’s existing sewer system.

The contract for the project began in January 2011  and was completed by early November. January is usually one of the wettest months in Darwin, so a critical issue was the control of flood water entering shafts and tunnels.  The situation became especially difficult in February, the city, which was already experiencing the heaviest rainfall on record was also battered by Cyclone Carlos.

Another of the challenges work crews faced was “the extremely shallow grade of the alignment, which was generally limited to .2%” And of course, there was the geology to deal with as well. The area to be tunneled was comprised predominantly of porcellanite and phyllite rock, which varied from fresh to highly weathered throughout the tunnel alignment and which also contained bands of stiff clay and granular material.

Despite all of these environmental obstacles, however, the sewer was completed on schedule and without incident. Part of the success came from meticulous oversight of the project but a larger part came from the tools chosen for it.  Engineers used a slurry tunnel boring machine (TBM) with a rock rather than a mixed-face head to do the main drilling and a centrifugally-cast fiberglass reinforced polymer mortar (CCFRPM) pipe to maintain low jacking forces.

It’s amazing what trenchless technology can do even in the most difficult circumstances.  And what’s even more impressive is that achievements like this happen all over the world every single day.  When it comes to  expanding, repairing or rehabilitating infrastructure, the choice is perfectly clear: trench less technology is the one and only way to go.

Photo credit: Bidgee

And that’s not the end of it. Leaky, corroded pipes are also responsible “for the loss of 2.6 trillion gallons of drinking water every year.” A congressional study shows that corrosion “costs US drinking water and wastewater systems over $50.7 billion annually.” At this rate, the problem will  result in more than $1 trillion in losses over the next two decades.

While corrosion is the main culprit, it doesn’t help that many municipal officials are co-opting for “a simple band-aid approach [that] repair[s] or replace[s] water mains with the same outdated iron pipes that currently make up much of [the] underground water systems.”  Such an approach may take care of the problem short-term.  But industry observers have noted that these practices are neither environmentally nor economically sustainable.

Technology may have the answer–or part of it.  Other pipe-types–most notably those made with polyvinyl chloride (PVC)–exist that are not only 100% recyclable but also remarkably durable. According to the American Water Works Association Research Foundation (AWWARF), PVC pipe has an estimated lifespan of 110 years or more. A European report found that longevity could actually be as high as 170 years.

But for technology to make a difference, local governments will need to make sure that all types of pipe technologies get considered for projects which sometimes doesn’t happen. Looking for and using new technologies will “drive innovation, resulting in more efficient, cost-effective, environmentally sustainable water systems.”

In the meantime, companies like Formadrain that specialize in infrastructure rehabilitation continue to push the envelope on their own to meet the challenges of the twenty-first century.  Traditional materials and methods may be best for some things, but when it comes to pipe repair and replacement high tech is only way to go.

According to Trenchless Technology online, Nashville is now putting the finishing touches on a 6,900 foot long water main that, along with pumping station upgrades, “will be able to handle 24 million gallons of water per day on average.”  While some sections of the new pipeline were put in using traditional open-cut methods, others were installed using a special shielded tunnel boring machine (TBM).

The machine itself was equipped with disc cutters varying in size from 6.5 to 15 inches in diameter. As the cutter head rotated, the discs “penetrate[d] the rock face and create[d] a ‘crush zone’ through which fractures propagate[d]. Afterwards, “material between adjacent crush zones [was] chipped from the rock face.” Special scrapers on machine scooped the debris into openings on the cutter head which then  transferred the material to a conveyor belt.

When this TBM was first launched in the summer of 2011, “an unexpectedly high volume of water flowed into the tunnel.”  Work crews had to use submersible pumps to eliminate the water problem which threatened to damage the electrified locomotive equipment involved in the project. Technicians were still able to complete two tunnels, one measuring 900 feet and the other 500 feet, by November 1 and finish the installation during the winter. The system will be fully operational by the end of this month.

Trenchless technology isn’t just for rehabilitating pre-existing pipelines. Methods such as trenchless tunnel boring help to create new systems that growing cities around the world like Nashville need to support infrastructure expansion projects.  As the world changes, so does trenchless technology: nothing else adapts better!

The excavation itself was part of a massive sewer upgrading project undertaken by the nearby city of Sydney. The resulting 13.4 km Katoomba Carrier tunnel “was to be one of the longest single-drive tunnel boring machine (TBM) tunnels at the time.” The project was so successful that it achieved  advance rates that are still considered outstanding almost two decades later.

The TBM project, which began in 1993, was faced with the daunting task of having to tunnel through sandstone that had a “high abrasivity and quartz content [which caused] software to the cutterhead.” Fortunately, the rock “remained fairly consistent for the whole of the tunnel, so an open-type TBM was determined to be adequate.”

Interestingly enough, the original project called for several tunnels rather than one that was continuous. Experts believe that this is what led to the improved advanced rates and greatly-lessened impact to the landscape. This latter outcome was especially important–and welcomed–because the Blue Mountains are a world heritage site.

Part of what contributed to the overall success of the project was using a continuously advancing conveyor that eliminated the need for traditional debris removal cars. Such a conveyor had never been used for longer-length boring projects, but engineers managed to create a system that performed without a single hitch.

History shows that challenges in the world of municipal pipe repair and replacement will always exist. But trenchless technology will continue to redefine industry standards for rehabilitation through the ingenuity and innovation that has become its hallmark.

In July 2010, the Chicago sewer system faced a major emergency when an unusually heavy rainstorm dumped seven inches of rain on the city in just a few hours. Less than two weeks later, another storm brought more rain to the city. The excess water “undermined a major sewer line and… led to the dramatic collapse” of a section running under Marquette Avenue, one of the busiest streets in downtown Chicago.

It took cleanup crews weeks to take care of the mess. But in the midst of repairs, technicians discovered that in the midst of the collapse, one manhole remained structurally sound. And this was because that manhole had been among those to receive attention through Chicago’s ongoing $60 million manhole rehabilitation project, which first got started in 2006.

The engineers in charge of the project had two important things to think about when coming up with their repair plan. The first was mortar strength; the second was microbiologically induced corrosion, otherwise known as MIC, which is “now known to be a prime cause of concrete deterioration in wastewater systems.” MIC results when organically-produced sulfuric acid “attacks the concrete matrix and decomposes it into a crumbly white mass…which has no strength.”

They turned to trenchless technology to help them resolve the situation. In particular, they made use of a “high-strength cementitious grout, enhanced with… an antimicrobial additive,” that they applied with a “bi-directional spincaster to support and strengthen the old manholes from the inside.”  In so doing, this technique “actually supports the existing structure from within.”

What happened in Chicago is a reminder that no pipe system lasts forever.  That’s why trenchless tech engineers are constantly seeking innovative ways to extend the life of critical infrastructure.  When there’s a problem, count on trenchless technology to find the solution!

Photo credit: porbital

Technicians used a special leak detection device equipped with a video camera to do an internal video and leak detection inspection. They initially thought the damage was located above Big Walnut Creek, the area where the damaged water main ran. They were wrong: the hole was under the river.

The first problem was gaining access to the main and providing ventilation for the workers. The Columbus Division of Water and Power (DPU) “constructed two manways, one being located about 150 feet from section to be repaired.” Technicians then designed “a special rigging to insert into the pipe, allowing [crewmembers] to patch the hole and apply the carbon fiber lining.”

The actual carbon fiber wrap itself was “saturated with epoxy outside the pipe.” This saturated material was then “conveyed into the pipe on a spool and adhered to the pipes surface, covering about a 20-foot section. The entire operation took just two weeks and cost the city of Columbus $250,000. The estimated life expectancy of this lining is  about 50 years.

Accidents can happen. And they’re always harder to deal with when they affect infrastructure that serves large populations and important municipal services. But thanks to trenchless technology and a little old-fashioned ingenuity, even most difficult problems can get resolved quickly and efficiently.  It’s the future-made-real today!

According to Trenchless International online, Montréal “spends a tremendous amount of money [every year] to repair water breaks, in addition to the costs related to the water lost in the process.”  And no wonder.  The city’s Water Services Division (WSD) manages over 2,640 miles of water mains, of which 2,200 miles are small diameter distribution mains, which serve more than 1.6 million people, businesses and industries.

The WSD itself has been in existence just seven years. Before that, it was known as the Water Division and was “decentralized between the city center and the 19 boroughs” that comprise Montréal. At the same time the WSD came into being  “the city also started an asset management program, whose master plan proposed massive investments in its water and wastewater infrastructures including the rehabilitation of its water mains, for the next 20 years.”

In an effort to save money, Montréal has been using CIPP liners to rehabilitate small diameter distribution water mains. And that investment has been paying off. Between 2008 and 2010, the city saved over $US58.3 million in direct costs for the structural rehabilitation of approximately 120,000 feet of water mains, compared to replacing the pipes using the open-cut method.

The CIPP liner is just one of the innovations that is making it possible for big cities with shrinking budgets to meet the needs of the people they serve. When it comes to cost-efficient solutions that work, nothing beats trench less technology!

According to Trenchless International online, Engineers will use CIPP to “reduce the amount of flow, strengthen the pipes and improve the sewer system operations and efficiency.” Better still, “the upgrades will provide capacity sewer system and reduce the potential for sewer overflows during times of heavy rainfall.”

The project will take place in phases. The first will involve technicians inspecting sewer pipes and manholes using remote video cameras.  To accomplish this task, they will lower this equipment will into the Freeport sewer system from street level through existing manholes. The technicians will then clean both the pipes and the manholes.

After the system has been scrutinized, “there will be a two-to-three month period where the camera footage will be reviewed and evaluated and construction work planned.” The City of Freeport Water and Sewer Commission will then determine where construction and repairs will begin in the system.

What made the CIPP installation process so attractive to Freeport city officials was that “it does not require digging, is less disruptive and can be completed in one day versus conventional open trench replacement, which would take several months.”

The project will rehabilitate about one-tenth of the total sanitary sewer collection system. And the planned fixes will lessen the likelihood of sewer backups and  reduce up to 6 million gallons per day of inflow and infiltration during the city’s heaviest rainfalls.

CIPP technology are helping cities around the world revamp aging sewer systems in ways that are as convenient as they are cost-effective. When it comes to innovation, nothing beats the trenchless way!

Federal highway programs were allotted $39 billion through the highway trust fund. This represents a 5% drop in the total amount of money ($41 billion) available to the same programs last year. Water infrastructure programs, such as the Clean Water and Drinking Water State Revolving Funds, also took a hit.

The bill mandating these water infrastructure reductions targeted the Environmental Protection Agency (EPA), “cutting $101 million from the State Revolving Fund (SRF) budgets.” The reduction in federal investment that this represents could cost those companies that supply the water industry $12 million in lost market opportunity. This is because about  “12% of all water utility bids [are] attributable to purchase, rental and leasing of construction equipment, and to the cost of dealer-performed equipment repairs.”

And the cuts don’t stop there. The Clean Water SRF that states use “for water quality protection and wastewater infrastructure projects” will receive $50 million less than it did the year before. And the Shrinking Water SRF, “which provides states the resources for potable water infrastructure projects,” will get $44 million less than it did in 2011.

What this ultimately boils down to is that already cash-strapped cities around the country are having to do more for America’s aging infrastructure with less money than ever before. This is where trenchless technology steps in. Every day, engineers are successfully creating cost-saving technologies using computers, lasers and the most modern materials available to solve problems that more expensive traditional trench-based methods can’t. Got a tight budget? No dig means no problem.

But recent technological developments are making CCTV more effective than ever before. According to Trenchless Technology online, engineers are now using  laser scanning in addition to CCTV to give wastewater managers the information they need. Laser scanning actually refers to two specific laser technologies: light detection and ranging (LIDAR) and structured light profile.

These technologies “are similar in that they only take measurements above the fluid level and do not work underwater.” LIDAR “works by bouncing photons of light off of an object (in this case, the pipe wall) and measuring how long it takes for that light to return to the LIDAR scanner.”  Engineers can then convert the travel times of individual photons into a distance measurements they can use to reconstruct a full three-dimensional model of a pipe interior.

Structured light profiling uses a visible laser along with a conventional CCTV camera. The laser “projects a red ring onto the pipe wall at a precise distance in front of the CCTV camera.” When the CCTV camera lights are turned off, this red ring becomes easily visible in the image. The size and shape of the red ring reveals the state of the pipe itself. An oval ring means the pipe is deformed or misshapen and a ring that’s close to the edges of the camera’s image means that the pipe is either corroded or enlarged.

In an era of severe budget shortfalls, laser and trenchless technologies are now combining in ways that allow wastewater managers do the impossible: use limited funds to not only reduce risks to aging infrastructure but also maintain service levels at low cost to consumers. Clearly, trenchless technology is “shining the light” on innovations that are helping cities and businesses around the world move into the future and into an age of sustainability.