Case Study: Tough Sewer Clearance for Thames Water in London SE1

A Lateral Approach from IWJS Achieved a Solution for Thames Water


Thames Water was presented with what seemed to be an insurmountable and potentially extremely expensive sewer clearance problem. However a solution was found to be at hand, courtesy of IWJS, when they took over this new challenge for major client Thames.

The serviceability of the sewer located at Waterloo in London had become severely affected by 8 cubic metres of C40 high strength, heavy construction grade cement. This challenging situation seemed a thorny problem that could have presented enormous civil engineering costs potentially for the client and caused major disruption. Especially as the sewer was located within a highly busy central London urban area, therefore it was difficult to rectify the problem without affecting traffic flows adversely for prolonged periods.

IWJS was therefore tasked by Thames to come up with a more creative, cost effective solution, without resorting to a radical and hugely expensive civil engineering intervention. Following a comprehensive survey of the sewer initially by IWJS, to ascertain the full extent of the problem, a full sewer clean was then scheduled. This would follow after the careful removal of the concrete and silt from the 1.2 metres elliptical profile sewer approximately 160 metres in total length.

The Challenge Ahead

Presented with the task, IWJS examined the problem thoroughly from an open perspective that required lateral thought and ingenuity to arrive at a workable solution. A uniquely creative approach was proposed by IWJS, working collaboratively with civil engineering partners, as this was found to be the best way forward, to achieve a cost effective solution. Thames Water therefore commissioned IWJS to head up and carry out the project.

IWJS acted as the principal contractor working alongside First Intervention Team (F.I.T) and major civil engineering partners Amey and McAllister.

Early planning meetings took place to orchestrate the smooth delivery of the project and minimalise any disruption to the area.  With essential traffic management being arranged to provide a temporary bus stop suspension and pavement closure within 2 metres of the curbside. Due to the busy central urban area, much night working had to be employed to deliver the project with as little impact as possible.

The adopted plan was for the McAllister crews to enter in the upstream manhole outside a public house. There inserting bungs to stop the flow, enabling the Amey mining crew to enter at the downstream manhole to drill out the offending concrete from the line. IWJS positioned a tanker adjacent to the upstream manhole strategically, to control the flows safely around the clock, enabling the work to continue unimpeded for the teams working below in the sewer.

Obstacles to Overcome

However, upon closer inspection the McAllister teams were unable to insert the bungs, due to excessive silt constricting the line.  IWJS then carried out a line clean of approximately 130 metres downstream to remove the silt effectively, thus allowing this essential operation to proceed smoothly as planned.

The McAllister team was then able to enter the manhole to insert the bungs and inflate them. Once these were in position and inflated, the Amey mining team was then able to enter the manhole downstream to commence drilling and secure removal of the concrete. With the rescue team (F.I.T.) on hand for all entries into the manholes to ensure maximum safety at all times.

A Positive Outcome

The safe removal of the highly tough concrete proved to be a laboriously slow process. However, once all of the concrete had been removed from the sewer successfully, IWJS was then able to carry out a full clean and provided a further monitoring survey to ensure the line was completely free. The end result of this challenging project, to restore the compromised sewer back to a free flowing line, was achieved effectively. Thames Water was highly delighted with the outstanding results attained, with minimal cost and disruption to their services and the area.

With the mission being fully accomplished, Thames gratefully acknowledged IWJS for their professionalism and skill in managing such a challenging and difficult project.



M62 Major Relining Project for A-one-+ and CR Civil Engineering


M62 Major Relining Project for A-one-+ and CR Civil Engineering


Few motorways in the UK approach the M62 in terms of the huge volumes of traffic it carries, especially HGVs, on the route between Yorkshire and Lancashire. As the M62 is literally the main artery carrying the lifeblood of container traffic between the major northern commercial ports of Hull and Liverpool.

Keeping that traffic flow going constantly around the clock on the M62 is a primary aim of Highways England. With the drainage beneath the motorway and verge culverts being essential, to help remove quickly the high volumes of surface water, thus keeping the primary arterial route safe for traffic.

With that purpose in mind, major waste water management company IWJS being a leading player in drain re-lining, was awarded a significant contract valued at £750,000 from lead client A-one+ and main civil engineering contractor CR Civil Engineering. To refurbish aging and damaged drains laid in the initial construction phase of the M62 dating back from 1971-1976.

Employing the Latest Innovations in UV Relining

The contract was awarded not only for the solid reputation developed with A-one+ over the last five years by IWJS, but for its leading expertise in using the very latest technology for UV drain relining. Employing state-of-the-art technology that is the most innovative available on the market from German company ProKasro. IWJS was the first company in the UK to adopt the custom built ProKasro 4×4 Mercedes computerised CCTV control unit and its comprehensive suite of robotic UV relining equipment. Adopting the ProKasro system offers the benefits of quicker preparation, superior relining speed and higher product quality in comparison with much older more conventional techniques. Also employed and controlled remotely from within the unit, are robotic cutters which have added further flexibility in adapting existing sealed drains, for them to become effective land drains under the motorway’s verges. With minimal cost and disruption to the drains beneath the verges being key benefits to the client.

Managing this major relining project for IWJS until his tragic death in January 2018 was Contract Manager, Andrew Simpson. He had this to say about this significant work from client A-one+ and delivering the work:

“We’ve built a solid working relationship with A-one+ over the last five years in Area 12 by achieving recognition on their approved suppliers list. Having established a reputation for good work that’s been delivered on schedule and to budget, mainly for drain and gully cleaning for them. They were aware of our reputation for high quality relining work and our significant investment in the innovative ProKasro UV relining rig, to maintain our lead as one of the top specialist drain relining companies in the UK. So choosing IWJS for such a high profile relining contract was the right way forward for them, to ensure its effective delivery within the project’s allocated budget.”

Andrew went on to add:

“The contract covers a key section of the M62 between J30 and J31, along the central reservation and verges over a total of 5400 metres (5.4 km). Obviously because of the nature of the work and the high volumes of heavy commercial traffic, we had to minimise any disruption to vehicle flow, so the majority of the work has to be done at night. One of the key parameters was not simply the need for speed in delivering the project, but for a high quality drain relining product that needed a minimum 50 year lifespan. This being due to the conversion of the central reservation area, to a concrete barrier and apron incorporating the surface water drainage system, so minimum maintenance and maximum longevity was crucial.”

Project Challenges

Work began in September 2017 with the target completion date set for March 2018. Unusual to the project is the high profile it has at night while the contract is underway and the volume of the relining work being delivered on such a major route as the M62. Innovation in managing such a high profile project, required extensive collaborative planning with Highways England and the use of ‘lean’ working to maximise efficiencies in both working and use of resources. Apart from the dedicated Mercedes 4×4 ProKasro computerised CCTV control unit, a Müller recycler bearing the IWJS 40th Anniversary livery, has also been employed on the project. Apart from the major relining work, additional survey inspection, culvert and gully cleaning work and removal of any drain obstructions, has been required as a comprehensive package of services delivered over the project’s life.

Delivery of the project has gone ahead so smoothly and ahead of schedule, that this has resulted in the further bonus of new UV relining work with A-one+ on the M621 being awarded to IWJS.


40th Anniversary Celebration vehicles

As part of their 40th year anniversary celebrations, IWJS are having every new vehicle delivered this year with specially designed livery. The vehicles will be a mix of JHL and Muller build with most of them coming in special edition black with gold and silver livery. The first black vehicle arrived this week and we think it looks great! IWJS pride themselves on exemplary service levels and absolute commitment to exceed customer expectation. Please contact us for more details.


wincan VX

Wincan VX – The future of CCTV reporting

IWJS are making a large investment into the very latest in CCTV pipeline condition survey reporting. This investment comes in the form of the brand new Wincan VX software which is a totally new system compared to previous upgrades.

Wincan VX gives the end user access to much more data in a simple to use format available through a web portal opposed to the old DVD and hard copy (although these are still available). The decision was taken to invest in this system not just because IWJS are leaders when it comes to embracing new technology but also because of the environmental impact.

“We used to spend thousands of pounds printing reports, buying and burning DVDs which then were posted and delivered to the client. This new system saves all of this and gives our customers a much faster, greener and cleaner set of data” – Peter Maasz – Business Development Director.