A fatberg is a rock-like mass of waste matter in a sewer system formed by the combination of flushed non-biodegradable solids (such as wet wipes) with fat, oil, and grease (FOG) deposits. [1] [2] [3] The handling of FOG waste and the buildup of its deposits are a long-standing problem in waste management, with "fatberg" a more recent neologism. [4] Fatbergs have formed in sewers worldwide, with the rise in usage of disposable (so-called "flushable") cloths. Several prominent examples were discovered in the 2010s in Great Britain, their formation accelerated by aging Victorian sewers. Fatbergs are costly to remove, and they have given rise to public awareness campaigns about flushable waste.
Fatbergs form at the rough surfaces of sewers where the fluid flow becomes turbulent. In pipes and tubes with smooth inner linings, fluid near the containing wall flows only slightly slower than fluid in the central channel of the pipe; thus, the whole volume of fluid flows smoothly and freely. When fluid encounters an obstruction, a resulting swirl of water starts trapping debris. Fatbergs occur in sewer systems around the globe, in cities and smaller towns. [5]
An obstruction can be any type of rough surface capable of snagging debris. In brick or concrete sewers there may be surplus cement drips, damaged brickwork, or loose mortar joints damaged by frost heave. In any sub-surface pipe, even of the most advanced design, penetration by foreign intrusions such as tree roots is a commonplace cause of a fatberg blockage.
Fatbergs are not just the result of fats that have congealed through cooling. The lipids in fatbergs have undergone a process of saponification. [4] [1] [6] Fatbergs thus require four main components: calcium, free fatty acids, FOG, and water. [4] Comprising not only wet wipes and fat, fatbergs may contain other items that do not break apart or dissolve when flushed down the toilet, such as sanitary napkins, cotton buds, needles, [7] condoms, and food waste from garbage disposal units washed down kitchen sinks. [2] [8] [9] The resulting lumps of congealed material can be as strong as concrete, and require specialist equipment to remove. [2] In the United States, almost half of all sewer blockages are caused by grease, [10] combined with the evergrowing use of wipes that end up in sewer systems. [11]
Fatbergs can cause blockages in sewer systems. Giant fatbergs have blocked sewers in London, New York, Denver, Valencia, and Melbourne. [5] Blocked fat reacts with the lining of the pipe and undergoes saponification, converting the oil into a solid, soap-like substance. [7] Grease and fat blockages can cause sanitary sewer overflows, in which sewage is discharged into the environment without treatment. [10]
Fatbergs have been considered as a source of fuel, [12] specifically biogas. [13] Most of the fatberg discovered in Whitechapel in London in 2017, weighing 130 tonnes (128 long tons; 143 short tons) and stretching more than 250 metres (820 ft), was converted into biodiesel. [7] [14]
Fatbergs can be mitigated through public awareness campaigns about flushable waste and grease traps for filtration at the source. [6] Many U.S. municipalities require restaurants and food processing businesses to use grease interceptors and regulate the disposal of FOG in the sewer system. [15] Campaigns have been launched against wet wipes because of their effect on sewer systems, includes by Surfers Against Sewage, the Marine Conservation Society and other environmental NGOs who called on the UK's Advertising Standards Authority to end “misleading” branding and packaging. [16]
In 2022, Australia and New Zealand developed a product labelling standard to help determine if a product is flushable. [17] [18]
Fatberg is a compound of the words fat and iceberg . The word was used in 2008 to describe "large, rock-like lumps of cooking fat" washing up on beaches in Wales, and by 2010 was used in reference to sewer-blocking fat deposits in London. [19]
The word was added to Oxford Dictionaries Online in 2015. [20] The term is used by authorities at Thames Water [2] and South West Water, [21] both in southern England.
Sewerage is the infrastructure that conveys sewage or surface runoff using sewers. It encompasses components such as receiving drains, manholes, pumping stations, storm overflows, and screening chambers of the combined sewer or sanitary sewer. Sewerage ends at the entry to a sewage treatment plant or at the point of discharge into the environment. It is the system of pipes, chambers, manholes or inspection chamber, etc. that conveys the sewage or storm water.
A sanitary sewer is an underground pipe or tunnel system for transporting sewage from houses and commercial buildings to a sewage treatment plant or disposal.
A drain cleaner, also known as drainopener, refers to a person, device, or product used to unblock sewer pipes or clear clogged wastewater drains. This term typically applies to chemical, enzymatic, or mechanical tools such as commercial chemical cleaners, plumber’s snakes, drain augers, bio-enzyme solutions, or toilet plungers. In some contexts, it may also refer to a plumber or professional who specializes in drain cleaning and maintenance.
A plumbing fixture is an exchangeable device which can be connected to a plumbing system to deliver and drain water.
Rendering is a process that converts waste animal tissue into stable, usable materials. Rendering can refer to any processing of animal products into more useful materials, or, more narrowly, to the rendering of whole animal fatty tissue into purified fats like lard or tallow. Rendering can be carried out on an industrial, farm, or kitchen scale. It can also be applied to non-animal products that are rendered down to pulp. The rendering process simultaneously dries the material and separates the fat from the bone and protein, yielding a fat commodity and a protein meal.
Newtown Creek, a 3.5-mile (6-kilometer) long tributary of the East River, is an estuary that forms part of the border between the boroughs of Brooklyn and Queens, in New York City. Channelization made it one of the most heavily-used bodies of water in the Port of New York and New Jersey and thus one of the most polluted industrial sites in the United States, containing years of discarded toxins, an estimated 30,000,000 US gallons of spilled oil, including the Greenpoint oil spill, raw sewage from New York City's sewer system, and other accumulation from a total of 1,491 sites.
A wet wipe, also known as a wet towel, wet one, moist towelette, disposable wipe, disinfecting wipe, or a baby wipe is a small to medium-sized moistened piece of plastic or cloth that either comes folded and individually wrapped for convenience or, in the case of dispensers, as a large roll with individual wipes that can be torn off. Wet wipes are used for cleaning purposes like personal hygiene and household cleaning; each is a separate product depending on the chemicals added and medical or office cleaning wipes are not intended for skin hygiene.
A grinder pump is a wastewater conveyance device. Waste from water-using household appliances flows through the home’s pipes into the grinder pump’s holding tank. Once the wastewater inside the tank reaches a specific level, the pump will turn on, grind the waste into a fine slurry, and pump it to the central sewer system or septic tank.
Anglian Water Services Limited is a water company that operates in the East of England. It was formed in 1989 under the partial privatisation of the water industry. It provides water supply, sewerage and sewage treatment to the area formerly the responsibility of the Anglian Water Authority. The remaining functions of the authority were transferred to the Environment Agency. Anglian Water is regulated under the United Kingdom Water Industry Act 1991.
A combined sewer is a type of gravity sewer with a system of pipes, tunnels, pump stations etc. to transport sewage and urban runoff together to a sewage treatment plant or disposal site. This means that during rain events, the sewage gets diluted, resulting in higher flowrates at the treatment site. Uncontaminated stormwater simply dilutes sewage, but runoff may dissolve or suspend virtually anything it contacts on roofs, streets, and storage yards. As rainfall travels over roofs and the ground, it may pick up various contaminants including soil particles and other sediment, heavy metals, organic compounds, animal waste, and oil and grease. Combined sewers may also receive dry weather drainage from landscape irrigation, construction dewatering, and washing buildings and sidewalks.
First flush is the initial surface runoff of a rainstorm. During this phase, water pollution entering storm drains in areas with high proportions of impervious surfaces is typically more concentrated compared to the remainder of the storm. Consequently, these high concentrations of urban runoff result in high levels of pollutants discharged from storm sewers to surface waters.
Sanitary sewer overflow (SSO) is a condition in which untreated sewage is discharged from a sanitary sewer into the environment prior to reaching sewage treatment facilities. When caused by rainfall it is also known as wet weather overflow. Causes of sanitary sewer overflows include: Blockage of sewer lines, infiltration/Inflow of excessive stormwater into sewer lines during heavy rainfall, malfunction of pumping station lifts or electrical power failure, broken sewer lines. Prevention of such overflow events involves regular maintenance and timely upgrades of infrastructure.
A grease trap is a plumbing device designed to intercept most greases and solids before they enter a wastewater disposal system. Common wastewater contains small amounts of oils which enter into septic tanks and treatment facilities to form a floating scum layer. This scum layer is very slowly digested and broken down by microorganisms in the anaerobic digestion process. Large amounts of oil from food preparation in restaurants can overwhelm a septic tank or treatment facility, causing the release of untreated sewage into the environment. High-viscosity fats and cooking grease such as lard solidify when cooled, and can combine with other disposed solids to block drain pipes.
Cadogan Place is a street in Belgravia, London. It is named after Earl Cadogan and runs parallel to the lower half of Sloane Street. It gives its name to the extensive Cadogan Place Gardens, private communal gardens maintained for Cadogan residents. It is owned by Cadogan Estates.
A toilet is a piece of sanitary hardware that collects human waste such as urine and feces, and sometimes toilet paper, usually for disposal. Flush toilets use water, while dry or non-flush toilets do not. They can be designed for a sitting position popular in Europe and North America with a toilet seat, with additional considerations for those with disabilities, or for a squatting posture more popular in Asia, known as a squat toilet. In urban areas, flush toilets are usually connected to a sewer system; in isolated areas, to a septic tank. The waste is known as blackwater and the combined effluent, including other sources, is sewage. Dry toilets are connected to a pit, removable container, composting chamber, or other storage and treatment device, including urine diversion with a urine-diverting toilet.
The privy midden was a toilet system that consisted of a privy (outhouse) associated with a midden. They were widely used in rapidly expanding industrial cities such as Manchester in England, but were difficult to empty and clean. A typical comment was that they were of "most objectionable construction" and "usually wet and very foul". They were replaced eventually by pail closets and flush toilets. Similar systems still exist in some developing countries, but the term "privy midden" is now an archaism.
Gutter oil, trench oil, sewer oil and tainted oil are Chinese slang terms primarily used in China and Taiwan to refer to recycled oil.
Lanes Group plc are a British civil engineering group specialising in drainage and sewerage repair and railway works.
Gel wipe is a moisturizing gel applied to dry toilet paper for cleaning purposes, like personal hygiene, or to reduce skin irritation from diarrhea. It was developed in the 21st century as an environmentally sensitive alternative to wet wipes.
A sanitary manhole is a manhole that is used as an access point for maintenance and inspection of an underground sanitary sewer system. Sanitary manholes are sometimes used as vents to prevent the buildup of pressurized sewage gas. Additionally, they are used for debris removal, and application of chemicals such as degreaser and insecticide.
The consummate cautionary tale is that of London, where in 2013 a collection of wipes, congealed cooking oil and other materials totaled 15 [metric] tons, according to Thames Water, the utility company that removed it. It was known, like some previous occurrences, as the fatberg. "We reckon it has to be the biggest such berg in British history," Gordon Hailwood, an official with Thames Water, said at the time.