3-D drain scanning
A three-dimensional scan of a drain pipe or chamber. 3-D scanning can be carried out using an optical camera system or with a laser. The optical system creates a high-resolution image of the inside of a chamber. Both systems map the shape and dimensions of chambers and pipes, with a very high degree of accuracy.
Ambient cure resin
A resin used when repairing drains with lining systems. This resin cures in ambient temperature.
Channels, either aboveground or underground, that take water past other features, such as roads, railways, buildings and other water courses. Culverts are also used to channel subterranean water courses.
Cured in place pipe (CIPP)
A ‘no-dig’ pipe rehabilitation solution for drains that creates a new pipe inside the existing pipe. It is often the quickest, least disruptive and most sustainable way to repair damaged pipes. CIPP lining is especially useful when a pipe cannot be excavated.
A pipeline, which conveys foul sewage and/or surface water, runoff from a single property. It is usually of small internal diameter.
Drain dye test
A drain investigation technique that involves introducing a non-toxic powdered dye into the drain system. By monitoring the flow of the coloured water, pipe connections and blockage problems can be identified.
Digging down into the ground to access blocked pipes. This technique is often only used as a last resort due to the disruption it causes and the potential to cost more.
The use of powerful water jets to clean pipes and chambers and remove blockages.
Blockages are removed using flexible poles called drain rods. Poles can become stuck in pipes during drain rodding so the technique should only be used by experts.
The process of examining a drain to assess its construction, connectivity, and condition.
Drain tracing equipment is used to identify the precise location of a pipe underground. An example is a CAT and sonde. A sonde is a radio transmitter, usually attached to CCTV camera survey equipment which can be detected above ground by the CAT, a radio receiver.
Electro-mechanical pipe cleaning
Where it is unsafe to use water jetting, an electro-mechanical pipe cleaning device can be used to break through blockage material. This method is often used to clean soil pipes and downpipes in buildings.
FOG stands for fats, oil and grease. FOG can build up in drains and sewers leading from kitchens, restaurants and food factories, causing serious blockages. It is a key component of fatbergs.
A pipe liner can be used to repair a long section of sewer or downpipe using the CIPP process. These are often referred to as ‘full liners’ to distinguish them from shorter liners which are called local structural repairs, patch liners, or point liners.
Hot water and steam CIPP
A cured in place pipe (CIPP) lining system that uses hot water or steam to cure the resin impregnated in a liner. Water is poured into the pipe under pressure and heated to around 95 degrees centigrade to cure (harden) the liner. The technique is often used to install liners in culverts and larger pipes. A disadvantage of hot water CIPP lining is that it creates large volumes of water contaminated with styrene that leaches from the resin. This needs to be contained and taken for safe disposal at a specialist waste site.
Jet vac tanker
A specialist tanker that has both a water jetting system for cleaning pipes and a vacuumation system for sucking up wastewater so it can be taken away for disposal or pumped into another pipe system.
No dig repairs and sewer repairs
Drain repairs that can be carried out remotely without having to excavate a pipe. No-dig repair systems are therefore often the least costly and disruptive, and the most sustainable way to repair pipes.
Patch liners are short liners made up of tubes of glass reinforced plastic (GRP) or felt – usually up to 1.5m long – impregnated with resin that are used to rehabilitate pipes with faults in discreet locations. The liners are created by folding sheets of GRP and layers of resin. The material is then wrapped around a packer and installed in the pipe with a flexible rod or pulled through with a rope. Once the patch liner is at the repair location, the packer is inflated, pushing the liner against the pipe. The liner is then left to cure in ambient temperature. Patch liners are also called local structural repairs and point liners. They are used to repair cracks and other faults, strengthen pipes and smooth pipes, for example where joints are displaced, to reduce the risk of waste material snagging on sharp edges.
Pushrod drain survey camera
A CCTV drainage survey camera system used to inspect smaller diameter drains. A mini video camera and powerful LED light is located on the end of a long, flexible rod that can be pushed along a pipe. Pushrod cameras are used to survey pipes with diameters up to 150mm. The flexible rod is stored on a reel called a camera reel, which can be up to 200m long. An advantage of a pushrod CCTV camera is that it can be directed around sharp bends in a pipe. It is also portable so can be used in remote locations and throughout buildings.
Robotic CCTV survey camera
A remotely controlled drainage survey camera that is attached to a wheeled carriage, powered via an electric cable. Robotic camera systems, also called crawler cameras, are used for surveying pipes with diameters from 150mm up to 1600mm. The camera head can be controlled and moved by the CCTV drainage engineer to get the best view of the inside of a pipe.
A technique that uses remotely controlled mechanical devices to remove blockage material or modify pipework. Robotic cutters are powered hydraulically or by electricity. They can be used to remove roots, concrete, scale and objects that are protruding into pipes. The latter can include stakes and concrete piles that have been inadvertently driven into sewers. They can also be used to remove protruding pipework that creates snagging risks. Robotic cutters usually use grinders rather than bladed cutters.
Wastewater that contains human waste.
A pipeline, which normally conveys foul sewage and/or surface water runoff from more than one property.
Ultraviolet light (UV) CIPP lining
A cured in place pipe (CIPP) lining system that uses UV light to trigger catalysers in resin which is then cured (hardened) to create a new pipe within a pipe. The UV light is delivered by a flexible wheeled light train holding a series of powerful UV light bulbs that is pulled through the liner after it has been inflated with compressed air at a predetermined speed to optimise the curing process. UV pipe lining is often faster, more sustainable and less disruptive than hot water CIPP (see above) because it requires a smaller work area, curing times are faster and it generates no contaminated wastewater.
A specialist vehicle with a large tank and a vacuumation system used to remove and transport wastewater. Vacuumation tankers are often used to clear flood water or redirect it into sewers or nearby water courses – or to take it to authorised disposal sites.
A cesspit is a tank, buried underground, used to hold wastewater generated by a property. The wastewater is not treated. It is collected at regular intervals for disposal at an authorised site.
Another name for a cesspit (see above).
A drainage field, also known as a soakaway field, is a system of pipes used to safely drain effluent (liquid waste from a septic tank or sewage treatment plan) into the ground.
Inspection chambers are used to gain access to pipework, for example underground sewer pipes.
Drainage systems that are not connected to the main public sewerage system, and are therefore not serviced or maintained by water companies.
A septic tank is a buried tank that collects sewage from a property. The wastewater is subjected to moderate treatment by undergoing a settlement and separation process combined with simple anaerobic digestion. Effluent can then be discharged into a drainage field (see above) if allowed under general binding rules. Remaining waste must be regularly collected for authorised disposal.
Sewage treatment plants
Also known as package treatment plants, sewage treatment plants combine a wastewater settlement and separation process with a more sophisticated and more thorough bio-treatment process than with a septic tank. The effluent water is therefore cleaner. Effluent can then be discharged into a drainage field (see above) or watercourse if allowed under general binding rules. Remaining waste must be regularly collected for authorised disposal.
Another name for a drainage field (see above).
A wastewater pipe carries sewage from a property to the cesspit, septic tank or sewage treatment plant.
The water service pipe that carries water from the water main to the property boundary. The water company is responsible for maintaining this pipe.
Internal stop tap
A tap located inside a building for turning on and off the flow of clean water.
The process of looking for and locating a leak in a water system. There are different techniques for carrying out leak detection, depending on the location of the leak, its spread and the scale of the damage it has caused.
External stop tap
A tap located outside a building that controls the flow of water from the communication pipe along the supply pipe and into the property. The external stop tap is owned by the water company.
Water pipe tracing is used to locate the precise position of pipework underground and within a building. Pipe tracing can be essential to locate and fix a water leak, carry out other maintenance on the water supply system or allow other maintenance work to be carried out on or near the building.
Point water pipe repair
The process of repairing a pipe in one discreet location. It may involve having to excavate the pipe. The repair may involve replacing a section of pipe or fitting a specialist clamp over the hole causing the leak.
The pipe that carries the water from the communication pipe into the property. The property owner is responsible for the maintenance of the supply pipe.
Water pipe moling
A method used to replace all or part of a water pipe. Compressed air is used to force a moling head through soil. A new water pipe can then be inserted into the created underground channel.
Water pipe re-routing
This method involves altering the direction of part or all of the existing water supply pipe. This method is primarily used when the leak is difficult or impossible to access and/or the existing water supply pipe is likely to incur further leaks due to its current location.
Water pipe replacement
Where a water pipe has seriously deteriorated or is made of material that is no longer suitable, the water pipe can be replaced.
Water quality testing
Water quality testing is carried out to ensure a property’s water supply meets required standards and is safe to use. Water testing may be needed if there are concerns about contamination of drinking water supplies or of hot water systems.
Water service pipe
A water service pipe is the pipe that takes water from the water main to a property. It is made up of the communication pipe and the supply pipe.
An arboriculturalist report shows how trees, which are located nearby, can increase subsidence risks or cause real damage to properties.
A hole drilled into the ground around a structure to assess ground conditions and take samples for laboratory testing. Borehole investigations may form an important part of subsidence investigations to assess how the condition of soil and other substrates are affecting subsidence risks.
Crack and level monitoring
A process of monitoring the crack development and level movement across a property.
Laboratory root testing
The scientific testing of tree and plant roots to assess if they have contributed to, or may contribute to, subsidence or other structural damage.
Laboratory soil testing
The scientific testing of soil and other material samples to identify physical and chemical properties that influence subsidence risks.
Mackintosh probe in-situ testing
A technique used to identify the variability of soil structures at different depths.
Shear vane test
A test to measure the undrained shear strength of cohesive soil. This helps assess the likelihood of a soil breaking down, resulting in increased subsidence risks.
A vertical downward movement of a building foundation caused by the loss of support beneath it. Subsidence can occur suddenly or gradually.
Trial hole / Trial pit investigations
A technique used to assess the condition and material types in structure foundations. The opening of a trial hole allows key foundation measurements to be taken both to assess risks and plan remedial action if it is needed.
A technique used to identify the noise created by an underground water leak. Microphones and digital acoustic software allow engineers to assess the location and severity of the water leak.
Correlation leak detection
Detectors are placed around the location of a suspected leak. By analysing (correlating) the frequencies of the sound of the escaping water from these locations, the location of the leak can be pinpointed.
Damp meter detection
A damp meter, also called a moisture meter, can be used to detect and assess the levels of moisture in walls, floors and ceilings. This data helps locate the leak, assess its severity, the scope of the damage caused, and the actions needed to both stop the leak and repair the damage.
Dye leak detection
Water engineers place a non-toxic water-soluble dye in a water system and monitor the way it flows through pipes, and potentially out of them, to help locate pipe and tank leaks and other faults, such as faulty valves.
A body of water created by flooding, from a river, lake, drainage pipe or clean water pipe.
A camera system combined of a mini video camera and a powerful light on a flexible rod that can be used to look into pipes and other hard-to-reach locations. Inspection cameras can be used to find the sources of leaks, determine the scale of leaks or assess other maintenance issues.
Non-destructive leak detection
An array of inspection methods used to locate the source of water leaks without damaging walls, floors, or ceilings or having to excavate underground pipes.
Thermal imaging cameras, also called thermography cameras, are used increasingly to locate water leaks by detecting changes in temperature in walls, ceilings, and floors. The camera uses infrared light to detect heat and cold sources that cannot be seen by the naked eye. Water leaks will usually show up as colder patches.
Tracer gas analysis
A technique that uses a lighter-than-air gas to detect leaks. Gas is introduced into a water pipe. Highly sensitive gas sensors are placed above the suspected leak. When the bubbles of gas escape from the hole causing the leak, it is detected by the sensors. The gas used is hydrogen, combined safely with inert nitrogen.