As a leading provider of specialist projects throughout the UK and Northern Europe, Hydro-Cleansing Ltd (HCL) is no stranger to challenging jobs. From the inlets of sewerage works to 42-story skyscrapers with blocked risers, we’ve seen it all. Just a couple of years ago, we even answered a call from Paris to unblock some large trunk sewers when the incumbent contractor didn’t have the capability of our flagship vehicles Terminator and Megatron. And let's not forget our bespoke contracts in Plymouth, where Megatron had to be lifted onto a platform to remove sand from boreholes.
So, when asked to clean a sewer pipeline in a difficult and sensitive area, removing tenacious debris and blockages that had defeated numerous other contractors, it was an average day for HCL… or so we thought. This ended up being one of the most difficult jobs Hydro-Cleansing has tackled in our 24 years of operating.
Project Scope and Challenges
The project took place in the northern part of Portsmouth, where residents had been facing recurring drainage issues for years, including flooding in and around their homes. Despite knowing there was a blockage in the sewers, five different contractors had attempted to resolve the problem, each time claiming success, only for the issues to reemerge. The residents were understandably frustrated, as the pungent smell of sewage plagued their streets for years. One unfortunate resident had a manhole in their front garden; previous contractors had knocked down their brick wall to gain access, leaving it unrepaired and without compensation. When we informed the community about our upcoming work, including necessary road closures, the residents were understandably sceptical and found the disruptions annoying and unwarranted. Our team, led by one of HCL’s directors, took the time to speak to every resident, reassuring them of our respect and care for their environment.
To begin the project, an initial assessment was needed through the manhole in the front garden. Since we were using such large equipment, we used rubber matting over the grass to avoid damage. To protect the newly constructed front garden brick wall a timber frame was constructed using railway sleepers. The pavement also had railways sleepers laid down to protect the tarmac and to level our Megareel Unit.
After entering the sewage system, we quickly found that the drawn drainage map we had been given was outdated and not entirely accurate. This made it more challenging to map the sewage system with so many routes to explore. We found a 375mm pipe into a 425mm sewage line. The diameter transition can cause a number of issues such as trapping sediment in the transition zone, making them harder to dislodge and remove.
As we began our work, we faced not just the usual grime and waste but huge lumps of concrete, house bricks, reinforced metal rods, and pieces of wood positioned horizontally. These innocent-looking objects had become the perfect traps for foreign materials, creating blockages that built up over weeks, months, or even years, with no warning or alarm bells until it was too late.
As work continued, we discovered a 450mm line full of concrete, with only a small element allowing water to pour over the top. The previous contractor had merely poked the core out of the apple, but we were determined to clear the entire blockage.
Methodology and Equipment
As a FORS Gold accredited business, we are proud to say we operate in a sustainable and environmentally friendly way, always prioritising to minimise our environmental impact. Our advanced fleet is all under our FORS Gold accreditation proving our excellence and commitment.
- Terminator - The Terminator is the most powerful and the largest vacuum tanker rig ever built in the UK, it can perform 3 times quicker from 3 times deeper or further than the next best tanker. Equipped with a continuous dirty water recycling jetting pump capable of producing 2500psi@880ltr per minute, it was the only tanker for the job. It houses 2x liquid ring pumps that produce, but are not limited to, 8000cfm at 100% vacuum, enabling the recovery of heavy solid materials from vast distances, which was perfect for this job allowing us to enter difficult-to-reach manholes.
- Mega Reel – Essential for hard-to-reach areas, Mega-reel is our jetting hose that is 1000 metres long with a high-pressure jetting of 6000cfm! With a four-wheel drive (4WD) it can easily reach areas our vacuum tanker may not always be able to reach.
- CCTV Crawler Unit – Undertook the conditional survey of the sewer and was positioned at various locations along the section of the sewer to assist during the cleaning operation and report productivity.
- Bulk Tanker – a 4k bulk tanker delivered additional clean jetting water to the Terminator and removed excess grit/sewer debris to ensure optimal efficiency each day of the job. It also transported the waste to Hydro-Cleansings liquid waste treatment facility to ensure the waste was disposed of sustainably.
- Confined Space Unit – a two-man confined space team undertook and controlled an NC2 man entry required in the cleaning operation. They assisted in inspections and carried out testing.
- Super Combination Tanker – a super combination tanker was positioned at various locations downstream of the working party capturing additional loose debris that may have bypassed the main cleaning operations. This was vital as we were ensuring the pipes were thoroughly clean and we weren’t causing blockages further down the system.
- Welfare/Support Unit – the unit allowed our confined space team a place to change from their dirty equipment and housed a toilet, sink, and kitchen facilities for our engineers to take breaks and hold site meetings.
- Cutting Head – a 300mm cutting head was used to cut through the concrete, creating a loud whining sound that echoed as it drilled through.
Execution
For seven intense days, our engineers battled through every challenge. We cleaned the sewers, washed and jetted manholes, and ensured continuity from one end to the other. Despite the sewers changing direction without notification and outdated drawings, we relied on local knowledge dating back to 1972, inspecting old prebuilt drawings in the local library. From spending hours trying to navigate the sewers to relentlessly running around, our team put in all their effort and smashed it!
Outcome
Finally, on the seventh day, we completed the job. We cleaned just under 1000 meters of the sewerage system, removing concrete, bricks, and foreign objects. The sewer was running free and easy, much to the relief of the residents. Overall, 67 tonnes of waste was removed, a mammoth job to say the least!
This project will go down in Hydro Cleansing history and we keep one of the bricks removed in our office as a symbol of what challenges we can overcome when we put our mind to it. At HCL, we don’t just clean sewers; we solve problems and bring peace of mind to communities. With the power of Terminator, Megatron, and our team of passionate professionals, there’s no challenge too great. Contact us today and experience the Hydro-Cleansing difference for yourself.
For more information about our services and commitment to sustainability, feel free to reach out. We are here to support you with professional, comprehensive solutions for all your waste management, drainage, and specialist cleaning needs.
