Zhirberg

Zhirbergs are formed on the rough surfaces of sewer collectors in those places where the fluid flow becomes turbulent . In channels and pipes with smooth inner walls, the liquid at the wall flows only slightly more slowly than the liquid in the central part (lumen) of the pipe. Thus, the entire volume of fluid flows smoothly and freely . When the liquid collides with an obstacle, the resulting vortex begins to hold up the debris .

Any rough surface that can trap debris can become an obstacle. In brick or concrete sewers, these may include cement streaks, damaged brickwork or loose joints damaged by frosty smoking . In any underground pipe, even the most advanced construction, the penetration of foreign objects, such as tree roots, is a common cause of the appearance of a gerberg.

In sewers that carry alkaline liquids, lipids can calcify and solidify ^[4] . zhirbergs can include not only napkins and fat, but also other objects that do not disintegrate and do not dissolve, being washed into the toilet. For example, sanitary napkins, cotton buds , needles ^[5] , condoms , tampons, and food waste washed into kitchen sinks ^{[2] [6] [7]} . The resulting lumps of solidified substance can be as strong as concrete , and special equipment is required to remove them ^[2] .

Sometimes the fat blocked in the sewer pipe reacts with the lining of the pipe and is subjected to saponification , turning into a solid, soap-like substance ^[5] .

Fat clogging can lead to sewage spills, in which waste water is discharged into the environment without treatment. In the United States, almost half of all blockages in sewer systems are caused by fat ^[8] .

Zhirbergs are a source of fuel ^[9] , in particular, biogas ^[10] . Most of the gerberg, weighing 130 tons and more than 250 meters long, discovered at Whitechapel in London in 2017 , was converted to biodiesel ^{[11] [5] [12]} .

Damage caused by gerbergs can be reduced through public awareness campaigns on the waste being washed off and the installation of grease traps for filtering effluents near their source ^{[4] [13]} .

Zhirbergs are found in sewer systems around the world, in megacities and small towns. Giant gerbergs blocked sewers in London, New York , Denver , Valencia and Melbourne ^[14] .

Zhirberg - tracing paper with the original combination of the English words "fat" (fat) and "iceberg" (iceberg). Neologism has been used by sewer managers since 2013 ^[15] . The word was added to the online version of the Oxford Dictionary in 2015 ^[16] . The term is officially used by management of Thames Water ^[2] and South West Water ^[17] , located in southern England .

In the Russian media, the word zhirberg is sometimes used.

• August 6, 2013 : In a sewer beneath London Road in Kingston upon Thames , London, a bus was found about the size of a bus weighing 15 tons and consisted of edible fats and wet wipes ^{[18] [19]} .
• September 1, 2014 : health workers discovered and cleaned a lot of spent fat, wet wipes, food, tennis balls and wooden boards the size of a Boeing 747 in a sewer under an 80-meter stretch of road to Shepherds Bush , London ^{[20] [21]} .
• September 3, 2014 : The sewer system near Melbourne , Australia , was clogged with a large mass of grease and waste ^[22] .
• January 2015 : As part of its campaign against blocking drains, Welsh Water released a video showing a greberg in sewers in Cardiff ^[23] .
• April 2015 : A 40-meter greiberberg was removed from sewers in Chelsea . The elimination of the consequences took more than two months, and the damage caused is estimated at approximately 400,000 pounds ^[24] .
• July 2015 : A 120-meter long giberberg was discovered in Welshpool in mid- Wales ^[25] .
• January 2016 : a clog caused by a gerberg near Newcastle , New South Wales , Australia , damaged a sewage pumping station in Eleban . The zhirberg weighed about one ton, and it took four hours to remove it with a crane ^[26] .
• September 2017 : a gerberg with a length of 250 meters and a weight of more than 130 tons was found near Whitechapel in London ^{[27] [28]} . Its destruction took two months of work without days off and two million pounds ^{[29] [30]} . Two pieces of the gerberg were cut off on October 4, 2017 and after several weeks of drying were exhibited at the Museum of London from February 9, 2018 to June 2018 as part of the Urban Future of the City season ^{[31] [32]} . According to curator Vyki Sparkes , Girberg has become one of the museum’s most popular exhibits ^[33] .
• September 2017 : Under the streets of Baltimore , Maryland , a grebergine was found from frozen fat, wet wipes, and other waste, resulting in the drainage of 4.5 million liters of wastewater into Jones Falls ^[34] .
• April 2018 : it is assumed that the gerberg discovered at South Bank in London is larger than that found at Whitechapel ^[35] .
• December 2018 : Sewer workers in Sidmouth , Devon , discovered a girberg that was 64 meters long. It took workers eight weeks to remove it. ^[36] It was the largest gerberg found in the UK outside a large city ^[37] , and the largest in the history of South West Water ^[17] .