2010 Guatemala City sinkhole explained
The 2010 Guatemala City sinkhole was a disaster on 30May2010, in which an area approximately 65abbr=inNaNabbr=in in diameter and 300feet deep collapsed in Guatemala City's Zona 2, swallowing a three-story factory.[1] The sinkhole occurred for a combination of reasons, including Tropical Storm Agatha, the Pacaya Volcano eruption, and leakage from sewer pipes.[2]
Background
See also: 2007 Guatemala City sinkhole. Overall, the risk of sinkholes occurring in Guatemala City is very high and unpredictable.[3] One recent, similar sinkhole had collapsed in 2007, forming a pit 100m (300feet) deep.[4] [5] The 2007 Guatemala City sinkhole was formed by fluid from a sewer eroding uncemented volcanic ash, limestone, and other pyroclastic deposits underlying Guatemala City.[4] [5] The hazards around the pipe have since then been mitigated, by improved handling of the city's wastewater and runoff.[6] Several rainstorms also contributed to the sinkhole's collapse, as stormwater percolated into the ground, further dissolving the rocks beneath Guatemala City.[7] [8] The 2010 sinkhole was formed for similar reasons.[9]
Formation
Sewage pipes
The sinkhole formed due to volcanic pumice deposits, upon which Guatemala City is built. These deposits were unconsolidated and of low density, allowing easy erosion. According to Sam Bonis, a geologist at Dartmouth College, leaking pipes went unfixed long enough to create the conditions necessary for sinkhole formation because of lax city zoning regulations and building codes. Bonis also says that the Guatemala City sinkhole is a misnomer: sinkholes have natural causes, but this one was mainly artificial. In addition, according to Bonis, sinkholes are usually formed from limestone but there is no limestone hundreds of metres underneath Guatemala City. Bonis proposes that the sinkhole be renamed a piping feature.
Tropical Storm Agatha
Tropical Storm Agatha was first identified as a trough of low pressure off the western coast of Costa Rica on 24May2010.[10] On May 29, the depression intensified into a tropical storm and was given the name Agatha.[11] Later that day, the system intensified slightly before making landfall near the Mexico-Guatemala border with winds of 45abbr=onNaNabbr=on.[12] By the morning of 30May, the center of Agatha moved over the highest terrain in Central America, resulting in the dissipation of the low-level circulation.[13] Torrential rains from the storm widened the cavity, eventually causing the collapse of the sinkhole.[14]
Pacaya volcano eruption
On 27May, three days before Agatha became a tropical depression, the Pacaya volcano, located about 25abbr=inNaNabbr=in south of Guatemala City, erupted, killing at least one person and blanketing nearby areas with layers of ash.[15] The eruption prompted officials to shut down the country's international airport.[16] Upon the formation of Agatha, people feared that excessive rainfall from the storm could exacerbate the situation and trigger lahars.[17] This had the effect of clogging the underground pipes with soot, increasing the chances of pipe rupture.
Collapse and aftermath
Mariela Castañón, a reporter for the daily newspaper La Hora, reported that the ground collapsed suddenly, taking a three-story house that was used as a factory, and possibly a security guard, along with it. Electricity poles were also sucked in. Authorities said they could not confirm the security guard's death.[18] [19]
Because of the role played by sewage pipes in the sinkhole's collapse, Sam Bonis, along with other geologists, has demanded that the government inspect the sewer system more regularly.
According to officials, the sinkhole had similarities with another Guatemalan sinkhole which collapsed in 2007, which may also have been formed by ruptured sewage pipes.[20] [21] [22]
On a wider scale, immediately following reports of fatalities due to Agatha, a state of emergency was declared for Guatemala.[23] On 31May, the government started to deploy national aid, and donation centers for victims of the storm were opened across the country. According to the Office for the Coordination of Humanitarian Affairs (OCHA), schools in Guatemala were to be closed until at least 4June.[24]
Filling in the sinkhole
Immediately after the sinkhole's collapse, there were plans to fill it in with a soil cement made from cement, limestone, and water known locally as lodocreto ("mudcrete"). This substance was also used to fill in the 2007 Guatemala City sinkhole. However, another technique, which geologists call the graded-filter technique, in which the sinkhole is filled with successive layers of boulders, smaller rocks, and gravel, could possibly be a better solution.[25] This is because filling the hole in with cement diverts water runoff to other areas, potentially increasing the risk of sinkholes occurring in other parts of the city. The graded-filter technique, on the other hand, allows water to seep through.[26]
Notes and References
- News: Killer Sinkholes: Unexpected Holes Swallow Entire Families, Cars And Homes (PHOTOS) . Huffington Post . March 5, 2013 . Huffington Post . 2013-04-21 . Campbell. Andy . 2013-03-04 . https://web.archive.org/web/20130304164705/http://www.huffingtonpost.com/2013/03/01/killer-sinkholes-deaths_n_2791634.html . live .
- Getting Revved Up About Sinkholes!. Focus on Geography. 2014-06-01. 1949-8535. 97–100. 57. 2. 10.1111/foge.12031. en. Leslie A.. North. Jason S.. Polk. Daniel. Nedvidek.
- Web site: Guatemala Sinkhole, 2010. Minard. Anne. June 4, 2010. 3 July 2013. 21 October 2013. https://web.archive.org/web/20131021163552/http://news.nationalgeographic.com/news/2010/06/photogalleries/100604-sinkhole-pictures-around-the-world-guatemala-city/. dead.
- Waltham, T., 2008, Sinkhole hazard case histories in karst terrains. Quarterly Journal of Engineering Geology and Hydrogeology. vol. 41 no. 3, pp.. 291-300.
- Halliday, W. R., 2007, Pseudokarst in the 21st century. Journal of Cave and Karst Studies. vol. 69, no. 1, p. 103–113.
- Web site: Don't Call The Guatemala Sinkhole a Sinkhole . Jun 4, 2010 . 2013-05-06 . Reilly. Michael . 2013-10-29 . https://web.archive.org/web/20131029001440/http://news.discovery.com/earth/dont-call-the-guatemala-sinkhole-a-sinkhole.htm . live .
- Web site: Photo in the News: Giant Sinkhole Swallows Guatemala Homes . National Geographic . February 26, 2007 . 2013-05-05 . Chamberlain. Ted . 2013-10-25 . https://web.archive.org/web/20131025132747/http://news.nationalgeographic.com/news/2007/02/070226-sinkhole-photo/ . dead .
- News: Third body pulled from giant sinkhole . NBC News . 2007-02-24 . NBC . 2013-05-05 . 2013-10-21 . https://web.archive.org/web/20131021143030/http://www.nbcnews.com/id/17303991/ns/world_news-americas/t/third-body-pulled-giant-sinkhole/ . live .
- Web site: Sinkhole in Guatemala: Giant Could Get Even Bigger . National Geographic . June 1, 2010 . 3 July 2013 . Than. Ker . 27 October 2013 . https://web.archive.org/web/20131027182954/http://news.nationalgeographic.com/news/2010/06/100601-sinkhole-in-guatemala-2010-world-science/%23 . dead .
- Web site: Dave. Sandoval. May 24, 2010. Tropical Weather Discussion. May 31, 2010. National Hurricane Center.
- Web site: Stacey. Stewart. Todd. Kimberlain. National Hurricane Center. May 29, 2010. May 31, 2010. Tropical Storm Agatha Public Advisory Two. October 24, 2012. https://web.archive.org/web/20121024055447/http://www.nhc.noaa.gov/archive/2010/ep01/ep012010.public.002.shtml. live.
- Web site: Lixion A.. Avila. John. Cangialosi. National Hurricane Center. May 29, 2010. May 31, 2010. Tropical Storm Agatha Tropical Cyclone Update. October 24, 2012. https://web.archive.org/web/20121024055523/http://www.nhc.noaa.gov/archive/2010/ep01/ep012010.update.05292233.shtml. live.
- Web site: Daniel. Brown. National Hurricane Center. May 30, 2010. May 31, 2010. Tropical Depression Agatha Discussion Five (Final). October 24, 2012. https://web.archive.org/web/20121024055537/http://www.nhc.noaa.gov/archive/2010/ep01/ep012010.discus.005.shtml. live.
- News: Guatemala Sinkhole Created by Humans, Not Nature . National Geographic . June 3, 2010 . National Geographic . 2013-04-21 . Than. Ker . 2013-11-11 . https://web.archive.org/web/20131111023401/http://news.nationalgeographic.com/news/2010/06/100603-science-guatemala-sinkhole-2010-humans-caused/ . dead .
- News: Guatemala Volcano: Pacaya Eruption Kills TV Reporter, 3 Missing (PHOTOS) . Huffington Post . May 28, 2010 . 3 July 2013 . Llorica. Juan . 9 December 2013 . https://web.archive.org/web/20131209171440/http://www.huffingtonpost.com/2010/05/28/guatemala-volcano-pacaya-_n_593583.html#s94957title=Guatemala_Volcano . live .
- Web site: Guatemala warns of volcano danger . CNN . July 22, 2010 . 3 July 2013 . 8 March 2013 . https://web.archive.org/web/20130308041540/http://www.cnn.com/2010/WORLD/americas/07/22/guatemala.volcano/index.html . live .
- Web site: Robert. Campbell . Reuters . May 29, 2010 . May 29, 2010 . Guatemala girds for first Pacific storm of season . live . https://web.archive.org/web/20100601070939/http://www.reuters.com/article/idUSTRE64S1A620100529 . June 1, 2010 .
- News: Guatemala City sinkhole so big, so round it 'doesn't seem real' . Christian Science Monitor . June 1, 2010 . Christian Science Monitor . 2013-04-21 . Fieser . Ezra . Santo Domingo, Dominican Republic . 2013-10-01 . https://web.archive.org/web/20131001030543/http://www.csmonitor.com/World/Americas/2010/0601/Guatemala-City-sinkhole-so-big-so-round-it-doesn-t-seem-real . live .
- News: Hundimientos atraen a la prensa extranjera . 17 July 2010 . La Hora . 2013-04-21 . Castañón . Mariela . dead . https://web.archive.org/web/20131211150010/http://www.lahora.com.gt/index.php/nacional/guatemala/reportajes-y-entrevistas/131879-hundimientos-atraen-a-la-prensa-extranjera . 11 December 2013 .
- News: Sinkhole in Guatemala: Giant Could Get Even Bigger . National Geographic . June 1, 2010 . National Geographic . 2013-04-21 . Than. Ker . dead . https://web.archive.org/web/20131027182954/http://news.nationalgeographic.com/news/2010/06/100601-sinkhole-in-guatemala-2010-world-science/%23 . October 27, 2013 .
- Physical Modeling on Sand Erosion around Defective Sewer Pipes under the Influence of Groundwater. Journal of Hydraulic Engineering. 2013-01-01. 0733-9429. 1247–1257. 139. 12. 10.1061/(ASCE)HY.1943-7900.0000785. Guo. Shuai. Shao. Yu. Zhang. Tuqiao. Zhu. David. Z.. Zhang. Yiping.
- New Information on the Guatemala City Sinkholes from Post Collapse Investigations. EGU General Assembly Conference Abstracts. 2012EGUGA..14.1193H. 2012-04-01. 1193. 14. R.. Hermosilla.
- Web site: Herbert. Hernandez . Reuters . MSNBC . May 29, 2010 . May 31, 2010 . Pacific storm Agatha's rains kill four in Guatemala . dead . https://web.archive.org/web/20100601053301/http://www.msnbc.msn.com/id/37413356/ns/world_news-americas . June 1, 2010 .
- Web site: Office for the Coordination of Humanitarian Affairs . Red de Información Humanitaria . May 31, 2010 . June 16, 2010 . América Central - Tormenta Tropical Agatha Informe de Situación #1 . dead . https://web.archive.org/web/20120308065324/http://redhum.org/archivos/pdf/ID_7734_GG_Redhum-OCHA-Sitrep1_-_Tropical_Storm_Agatha-by_ROLAC-ESP-20100531.pdf . March 8, 2012 . es.
- The Guatemala City sinkhole collapses. Carbonates and Evaporites. 2011-11-15. 0891-2556. 103–107. 27. 2. 10.1007/s13146-011-0074-1. en. Rodolfo G.. Hermosilla. 129104329.
- Web site: How To Fix a Giant Sinkhole . Slate Magazine . June 4, 2010 . 16 September 2013 . Palmer. Brian . 28 September 2013 . https://web.archive.org/web/20130928183206/http://www.slate.com/articles/news_and_politics/explainer/2010/06/how_to_fix_a_giant_sinkhole.html . live .