Sewer surveys to the highest standard


Adam Wharton and John Bishop are the latest DSS Environmental CCTV team leaders to pass their OS19X  Pipe Condition Classification Course.

The 5 day course is designed to give an understanding of the key features and technology involved in pipe sewer classification work to the WRc Manual of Sewer Condition Classification – 4th edition.

The course covers the need for and role of sewer condition classification, the key features of the various categories of pipe sewer and how to recognise and code the conditions and features.

With these qualifications DSSE CCTV crews are able to provide a great enhanced service to our clients when surveying and reporting on their sewer infrastructure.

The reports enable the right action to be taken to ensure optimum performance of the sewer asset.

Training is a vital part of the business not only for the technical aspect, as in this case, but also to ensure the highest safety standards.

The environment in which our crews work can be hazardous and best practice, through training, reassures our clients that the asset, their staff and the public are well cared for.

DSSE is part of the IWJS group of companies and offers the full range of services for the waste water sector including CCTV surveys, sewer clearing, re-lining, small civils works and waste tankering.

More information on DSSE is available at or by phoning 0800 58 58 76.

Relining expertise at IWJS

The Task
What to do when you are faced with having to reline a 38m section of 750mm storm drain in a very demanding environment?

The site conditions meant that access to one end of the drain was on rough ground that suited 4×4 vehicles, the other end in tight residential roads a further 30 m on from the end of the relining section. In between, the drain running under houses and other structures.

When a major Water Utility company was faced with this particular set of problems, DSS Environmental Ltd demonstrated they had the capabilities and won the contract to undertake the works.

What we did

The three day project started by digging down to reveal the storm drain, cut through the top to gain access and build a tower to take the relining equipment.

Following a CCTV survey to finely assess and measure the problem section, a combination jet/vac unit was used to clean the drain followed by remote guided cutting equipment to remove tree roots.

A further CCTV survey confirmed the section was clean, clear and ready to take the liner.

The 2 ½ tonne pre-wetted (resin impregnated) liner that arrived in refrigerated transport on day two was winched through the access point and carefully positioned using the CCTV crawler as the underground eyes.

The next part of the process involved inserting a calibration liner inside the resin liner and using water to fill the ‘cali’ to press the resin liner to the sides of the drain ready for the curing process.

Using 3m BTU of heating capacity, the water in the calibration liner was heated to 80oC and kept at temperature for 8 hours to ensure the resin liner was properly cured.

Day three saw the safe removal of the equipment, a final CCTV survey to ensure the liner was fully functional and the making good of the site.

Safety is always paramount on this type of operation and the weather was constantly monitored. ‘Packers’ were used to temporarily stop the water flow throughout the three days and a Flexline tanker was on site 24/7 to over pump any rainwater if the weather turned. After all, that is the purpose of storm drains.

 The outcome

With a written report (including a CCTV survey DVD) sent to the client confirming a successful operation, IWJS have again demonstrated their expertise in the sewer relining and sewer repair sector.

Basildon Sewer Treatment Works

The Task

IWJS Ltd were contracted by ELS on behalf of Anglian Water to clean out three large storm tanks, each capable of holding 1.5 million litres of waste water, at the Basildon Sewer Treatment Works.
The storm tanks, designed to store overflow waste in times of heavy rain, had 15 years of accumulated debris to be cleared.

What we did

A phased approach was required as the treatment works had to remain operational throughout the process. Consideration also had to be taken regarding weather conditions to ensure the safety of the IWJS staff.

With the volume of debris and waste water present IWJS provided dedicated large scale vacuum pumping, high pressure jetting and screening units as well as experienced operators to ensure continuous operations.

Each storm tank took five days to clear with an additional three days work to clear the surrounding weirs and connecting culverts.

The collected solids, up to a metre thick along the bottom of the 58m long tanks, were separated from the waste water for safe disposal.

The screening of the waste as well as the recycling of the waste water during the high pressure jetting operations was an important factor in reducing the environmental impact of the operations.

The outcome

IWJS left each tank in a ‘as new’ condition to the delight of the works management team. The IWJS operators were praised for providing a very high level of service within the allocated time scales.

IWJS group fights the fat

A major sewer cleaning project around a busy Peterborough City road complex has just been completed by Industrial Water Jetting Systems on behalf of Anglian Water.

The A15, a major through road, was shut from Saturday evening (28th Jan 2012) to early Monday morning (30th Jan 2012) to allow the IWJS team to clear the city sewer of fat, rags and silt.
The cleaning operation was hazardous due to the sewer layout and its location under the busy A15. The scheduling of the works over a weekend was designed to minimise traffic disruption.

One Flexline combination unit, two recyclers, two CCTV surveying vans and one bobcat unit were used over the 36hr period. The experienced IWJS crews worked in shifts around the clock.

The work was part of a 12 week long programme to clear the sewer system under Lincoln Road from the city centre up as afar as Mountsteven Avenue.
Over 250 tonnes of fat, rag and silt have been removed.

Anglian Water operates a ‘Keep it clear’ scheme to inform businesses and homeowners about the consequences of putting fat and other wrong items down drains and toilets.
In Peterborough city centre blockages have fallen by 2/3rds since the scheme was introduced there, but there are still parts of the underground system badly clogged, and that’s were IWJS steps in to return the sewers to prime working condition.

Ivan Clarke, Depot Manager for IWJS Woolpit, was pleased with the operations success. ‘Detailed advanced planning of the work with Anglian Water worked well to minimise the road closure. We managed to complete the job ahead of target and that is a credit to our staff who worked hard over the weekend.’

The IWJS group operates three trading companies in the water and drainage services sector, IWJS Limited, DSS Environmental Limited and Aquajet GB Limited. With over 35 years of continuous trading experience, the three companies are trusted contractors to the water utilities, infrastructure groups, industrial companies, commercial concerns and domestic users.
The group has over 300 staff and operate from locations across the country on a 24/7 basis.

Pocklington Beck

The Task

Aquajet GB Limited was contracted by the Environment Agency to clear debris build up from Pocklington Beck. The activity was part of an on-going flood risk strategy following major floods in 2003 and 2007 and was subject to intense public scrutiny.

What we did

Around 350 tonnes of mainly rubble were removed. Following the clearance of the rubble and debris the beck is now free flowing and the flooding risk has been significantly reduced. However during the course of the works both native white and American crayfish were discovered in the beck.

Aquajet undertook to solve this issue with the Environment Agency. Detailed planning was required across multiple agencies. Aquajet staff caught and segregated the two species whilst recording the level of activity. The native species were released downstream away from the predatory American crayfish.

The outcome

Apart from the free flowing beck and significantly lower risk of flooding Aquajet received many plaudits for the way in which the environmental works were handled professionally and in a sensitive manner. Aquajet are a preferred supplier to the Environment Agency for clearing, CCTV surveys and other drainage services. With such dedicated staff you can see why Aquajet are thought so highly of.

Whittle Brook

The Task

Aquajet(GB) Ltd were engaged by the Environment Agency to carry out a full cleanse of this drainage asset. The condition of this asset was in particularly poor condition. In addition the work was to be carried out under tidal conditions and in a remote location.

What we did

A significant amount of debris was removed from the drain. As the site was remote, tidal and adjacent to a live railway and canal Aquajet(GB) Ltd coordinated with several other contractors to ensure that both their works and the other contractors works could be carried out in a safe and timely manner. To this end Aquajet had a Manager on site throughout the operation.

Specialist equipment was deployed during the works and man entry techniques were required supported by our own rescue team on site at all times. These teams are fully trained to a level that the Environment Agency allow them to work unassisted in the field to an acceptable safety level. Significant groundwork was required to return the asset to the required condition including landscaping, fencing and re-seeding the area.

The outcome

Another successful operation by Aquajet reducing flood risk for the Environment Agency.

Aquajet are a preferred supplier to the Environment Agency for clearing, CCTV surveys and other drainage services. With such dedicated staff you can see why Aquajet are thought so highly of.

IWJS increases its flexibility

The commitment of IWJS to invest in its fleet of specialist vehicles has been clearly demonstrated with the arrival of a new unique JHL Flexline 312 HP combination unit at the groups Woolpit head office.

The last few months have been very busy for IWJS with its acquisitions of DSS Environmental and Aquajet GB. The delivery of this JHL Flexline unit is part of the investment programme to accompany the groups’ growth.


Flexline units are used for the clearing of drains, sludge removal, tank and interceptor emptying. These operations form part of the services that IWJS performs for its clients in the water and drainage sector. The IWJS group is a top ten national provider of services to water utilities, construction companies, industrial, commercial and domestic users and continues to grow through excellent customer relations.

Based on a Mercedes Benz chassis IWJSs’ unique Flexline has a large 125mm diameter suction hose, a 140bar jetting unit with choice of hose reels and a 12m3 capacity tank. The tank also has a moveable internal wall to maximise either the clean water or waste carrying capacities, to suit client requirements.

Whilst Flexlines are already used within the 160 strong fleet several additions have been made to increase this particular vehicles’ versatility.

The addition of a bespoke 11,800 psi high pressure jetting unit, five times more powerful than normal, has been specified capable of hydro blasting surface cleaning including concrete cutting, root and scale removal within pipelines all with the added benefit of simultaneous suction recovery of the pumpable waste streams.
The Flexline is fully hydraulically driven providing efficient power with the benefit of reduced noise levels.

Safe and Experienced

High pressure jetting can be a hazardous operation and all operators have to be qualified to use this equipment. IWJS runs its own training school and are full members of the Water Jetting Association to ensure best practices are maintained.

Christopher Stewart, group managing director sees this delivery as a keeping of a promise. “We have made commitments to our customers to deliver a high quality and reliable service and this new Flexline with its unique capabilities is part of a package of measures to achieve that”