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Coastal erosion and village relocation: A Colombian case study

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Because of its tectonic setting, the Pacific coast of Colombia is subject to a variety of geological hazards, including earthquakes, tsunamis and associated phenomena such as regional and local coastal subsidence, flooding and soil liquefaction. Erosional trends are prevalent along much of the 700km long, low barrier island's shorelines of the Pacific littoral and land losses are enhanced by factors such as 30cm regional sea level rises associated to the occurrence of El Niño. Marine erosion is threatening more seashore littoral villages and worsening the already difficult socioeconomic conditions of most part of the inhabitants. Because of diverse and strong motivations to stay near the sea, the responses of barriers island's inhabitants to marine erosion has consisted in most cases of repetitive in-shore and along-shore directed relocations of villages, rather than definitive abandonment of the islands. In the long run, this procedure only has postponed the problem and led to repetitive relocations and economical losses. The recent inland relocation of El Choncho village, on the San Juan River delta, illustrates a different response to marine erosion. Although a new along-shore relocation was physically possible, inhabitants decided to abandon the barrier island and migrate to an interior, ancient beach ridge complex, applying a prudent solution which will be the most appropriate for other threatened villages of the Pacific littoral. A detailed geomorphologic mapping program must be conducted in order to identify appropriate sites for inland relocation of existing villages on the barriers islands of the Colombian Pacific coast.
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*Corresponding author. Tel.: #47-4-266-05-00; fax: #57-4-266-4284.
E-mail address: icorrea@sigma.ea"t.edu.co (I.D. Correa).
Ocean & Coastal Management 43 (2000) 51}64
Coastal erosion and village relocation:
a Colombian case study
Ivan D. Correa*, Juan Luis Gonzalez
Area de Ciencias del Mar, Universidad EAFIT, Apartado Aereo 3300, Medelln&n, Colombia
Abstract
Because of its tectonic setting, the Paci"c coast of Colombia is subject to a variety of
geological hazards, including earthquakes, tsunamis and associated phenomena such as
regional and local coastal subsidence, #ooding and soil liquefaction. Erosional trends are
prevalent along much of the 700 km long, low barrier island's shorelines of the Paci"c littoral
and land losses are enhanced by factors such as 30 cm regional sea level rises associated to the
occurrence of El Nino. Marine erosion is threatening more seashore littoral villages and
worsening the already di$cult socioeconomic conditions of most part of the inhabitants.
Because of diverse and strong motivations to stay near the sea, the responses of barriers island's
inhabitants to marine erosion has consisted in most cases of repetitive in-shore and along-shore
directed relocations of villages, rather than de"nitive abandonment of the islands. In the long
run, this procedure only has postponed the problem and led to repetitive relocations and
economical losses. The recent inland relocation of El Choncho village, on the San Juan River
delta, illustrates a di!erent response to marine erosion. Although a new along-shore relocation
was physically possible, inhabitants decided to abandon the barrier island and migrate to an
interior, ancient beach ridge complex, applying a prudent solution which will be the most
appropriate for other threatened villages of the Paci"c littoral. A detailed geomorphologic
mapping program must be conducted in order to identify appropriate sites for inland relocation
of existing villages on the barriers islands of the Colombian Paci"c coast. 2000 Elsevier
Science Ltd. All rights reserved.
1. Introduction
The Paci"c coast of Colombia, located at the northwestern corner of South
America (Fig. 1), is legendary for its luxuriant vegetation and rainy humid tropical
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0964-5691/00/$ - see front matter 2000 Elsevier Science Ltd. All rights reserved.
PII: S 0 9 6 4 - 5 6 9 1 ( 9 9 ) 0 0 0 6 6 - 6
Fig. 1. Location map of the San Juan River Delta on the Paci"c coast of Colombia.
climate. This largely isolated region lacks the basic infrastructure facilities in most
areas: road access is limited to two highways that connect the interior of the country
with Buenaventura and Tumaco (the only two commercial seaports on the Paci"c)
and air access is available only to a few cities in the region; to reach most parts of its
1300 km length littoral, it is necessary the use of small boats, navigating both by sea
and/or by the dense networks of #uvial and tidal channels crossing the coastal zone.
The socioeconomic conditions of the region are poor, the economy for most of the
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52 I.D. Correa, J.L. Gonzalez /Ocean & Coastal Management 43 (2000) 51}64
Fig. 2. Photograph of non-storm washover El Choncho. Note the lack of high waves in the Paci"cor
strong onshore winds.
inhabitants is subject to daily subsistence with the basic necessities far from being
adequately covered. Traditionally, the main economic activities have been timber
exploitation, "shing, shipping and gold mining, concentrated around the in#uential
areas of Buenaventura, Tumaco and other smaller development centers. In the last
decade, shrimp aquaculture and eco-tourism became important in some sectors of the
coastal zone.
Located at the zone of convergence of the Nazca and South American plates [1}3]
the Paci"c coast of Colombia has a long history of natural disasters, including four
earthquakes of magnitude 6.5 or larger in this century [4}6]. The Tumaco, December
12, 1979 earthquake, was the last major impact event on the southern Paci"c coast of
Colombia. It generated a sudden land subsidence estimated in 1.6 m along the littoral
zone and a large tsunami that completely destroyed several small villages along the
sandy barrier islands north of Tumaco. San Juan de la Costa, an open coast "shermen
village located 60 km north of this city was literally buried by a 3 m high water
column which drought at least 156 inhabitants; the port of Tumaco, with a population
of 25 000, did not su!er the direct impact of the tsunami because of some geomorpho-
logical protection and because the tsunami struck at low tide [7].
Although less impressive, the impacts of long-term shoreline retreat are acquiring
"rst-order socioeconomic importance along the Paci"c littoral. Given the growing
number of coastal villages exposed to marine erosion and the limited areas of high
ground on the barrier islands, the need for implementing valid strategies to cope with
the shoreline erosion and #ooding problems is evident (Fig. 2). For the small and poor
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I.D. Correa, J.L. Gonzalez /Ocean & Coastal Management 43 (2000) 51}64 53
Fig. 3. Radar image of the San Juan river delta. The location of villages on barrier islands is indicated.
INTERA image from 1992. Courtesy of INGEOMINAS.
communities located along the retreating shorelines, agricultural lands are rapidly
diminishing as a result of land losses and associated e!ects such as soil salinization. At
the end, relocation is and will be the sole possible response to beach retreat, but where
and when to relocate has not always been clear or properly done.
The case of El Choncho village, a community located on the coastal fringe of the
San Juan River delta, illustrates an example of the socioeconomic consequences of
marine erosion along the Paci"c littoral, and the human and geomorphologic factors
involved in the decision for relocating. This case represents a long-term perspective
which should be taken as an example of the correct response to shoreline retreat for
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54 I.D. Correa, J.L. Gonzalez /Ocean & Coastal Management 43 (2000) 51}64
other coastal communities along the low deltaic sectors of the Colombian Paci"c
coast.
2. General setting
Before its de"nitive relocation in 1997, El Choncho village was located on the El
Choncho barrier island, the southern most sandy active barrier of the San Juan delta
(Fig. 3). Located 90 km north of Buenaventura, the delta has a well-de"ned protrud-
ing lobate form with an emergent area of 800 kmand a shoreline length of 51 km.
The San Juan river has a course length of 345 km and a basin area of 17 000 km, the
second largest of the Colombian Paci"c coast. Mean annual precipitation in the basin
ranges from 6 to 7 m, with a reported maximum of 11 m/yr near the head waters [8].
The San Juan river has the highest discharge of any river on the Paci"c coast of South
America, a mean of 2850 m/s and a range between 600 and 6000 m/s, measured at
Cabeceras, 5 km upstream from the delta apex [9]. No individual discharge "gures
are available for each of the six active inlets of the delta.
The lower delta plain extends landward for 6}11 km and is under the direct
in#uence of tidal e!ects as evidenced by extensive mangrove intertidal #ats and by
a dense network of meandering tidal channels. Four sandy barrier islands, ranging in
length from 7}12 km and in width from 80}300 m, de"ne the seaward limit of the
lower delta plain. Some of these barrier islands have well-developed beach ridges with
maximum elevations of 1 m above spring tides. Former shoreline positions north and
south of the delta plain are identi"ed by remnants of older beach ridges and barriers
with an orientation roughly parallel to that of the present day shoreline.
Around the San Juan delta average spring tides have a range of about 4.0 m [10].
Dominant wave directions are from the west and southwest; wave energy is moderate
with wave lengths of 10}50 m and average wave heights of 0.5}1.5 m; storm wave
heights range from 1.5}3.5 m. As evidenced by the morphology of spits on barrier
islands, wave refraction is divergent at the axis of the delta and net longshore drift
along the delta is both south and north away from the axis. El Nino occurrences along
the central and south Paci"c coast of Colombia are manifested by an increase in sea
level of as much as 25}35 cm [11,12] (Fig. 4).
3. The community of El Choncho
The occupation of El Choncho barrier island dates back to 1906 when the "rst
inhabitants settled and raised pigs that were let to run free along the island. The
number of pigs was large and that is the origin of the island's name; choncho is
a Spanish word for pig. Occupation since 1906 has been continuous. The island was
known up to the 1970s for its numerous crops that included several basic agricultural
products for self-subsistence including rice, avocados, cassava roots, plantain banana,
oranges, mangoes and coconuts. `We did not have to worry about food at that timea
an old inhabitant told us, in reference to the fact that they did not need to import food.
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I.D. Correa, J.L. Gonzalez /Ocean & Coastal Management 43 (2000) 51}64 55
Fig. 4. Topex/Poseidon Image. Cycle 192 from Nov/30/97 to Dec/09/97. During this period sea level for the
west coast of northern South America was between 30 and 40 cm higher than normal, due to an intense El
Nino event. These data were obtained from the NASA Physical Oceonography Distributed Active Archive
Center at the Jet Propulsion Laboratory, California Institute of Technology.
At this time, the economy of El Choncho was mainly based on the exportation of
agricultural products (the village was famous by its fruits) and the exploitation of
timber and "shing. Some inhabitants received additional income by keeping and
maintaining several vacational beach homes owned by people from the interior and
by providing shelter for sporadic tourists and occasional research teams working in
the area. In a simple economy with non-accumulative prospects, most villagers used
their income to improve their living conditions. Individuals seeking better economic
possibilities migrated to Buenaventura and other bigger coastal communities.
A typical house in the old El Choncho village was built of wood, elevated on stilts at
heights of 1.5 m above the ground to accommodate #ood and washover potential.
They had a tin roof from which rain water was collected for domestic use; septic tanks
were used to discharged waste water.
4. Chronology of island erosion at El Choncho
Like all the delta barriers and other barrier islands along the Paci"c littoral, El
Choncho island experienced important morphological changes in recent decades. The
recent shoreline changes along the barrier's front were documented by comparing air
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56 I.D. Correa, J.L. Gonzalez /Ocean & Coastal Management 43 (2000) 51}64
Fig. 5. Representation of shoreline changes between 1968 and 1997 for El Choncho barrier island.
photographs and radar images from 1968 to present [13,14] and by interviewing the
long time inhabitants of the island. During this period, the island's front position and
con"guration changed signi"cantly as re#ected by (a) the formation of an extensive
sandy cuspate tidal #at at its northern end, (b) the development of a 1.5 km long beach
ridge system on its southern end, and (c) a total beach retreat of between 150 and
220 m along the 2 km long central segment of the island, on which the El Choncho
village and related agricultural plots were located (Figs. 5 and 6).
It is not known exactly when beach retreat started along the central part of the
island, but the "rst oral references of noticeable 1.5 m high permanent erosional beach
scarps in front of the village area date back to 1970}1975, suggesting preexisting
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I.D. Correa, J.L. Gonzalez /Ocean & Coastal Management 43 (2000) 51}64 57
Fig. 6. Air photo from 1993, showing the central part of the El Choncho Barrier Island, where the village
was located. Note width of island. At that time it was 110 m at the narrowest part. Also note the houses
dispersed on the front of the island. By this date all houses had been relocated at least one time, towards the
landward side of the island.
erosional conditions at that time. The development and emergence of the sandy
cuspate tidal #at on the northern end of the island predates the 1968 photographs; the
tidal #at trapped the sand drift and promoted erosional conditions in a downcurrent
direction on the island front. The normal annual cycle of beach changes on the island's
central part was one of beach retreat during October}November, and partial beach
recovery between January and April. Intense erosion a!ecting the seaside houses of
El Choncho village was "rst measured in 1989, beach retreat of 15 m between October
1988 and September 1989 was well documented [15,16]. Erosion rates in front of
El Choncho accelerated after the occurrence of the November 1991 magnitude 6
earthquake with epicenter just 40 km to the NW of the delta [17]. On El Choncho
village, the direct e!ects of the shock included soil liquefaction, land cracking and
water}soil expulsion. Although no quantitative estimates are available, land subsid-
ence e!ects are evidenced by the fact that the frequency of overwash on the island
increased two times a year (March and October during the highest tides) before the
quake, to at least once a month after the shock. According to inhabitants, the normal
beach cycle was disrupted by the event and erosional conditions prevailed throughout
the year. Beach erosion between April 1993 and November 1997 is well documented
by topographic pro"les that show a net beach recession of 60 m with an average rate
of 11 m/yr for this period (Fig. 7).
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58 I.D. Correa, J.L. Gonzalez /Ocean & Coastal Management 43 (2000) 51}64
Fig. 7. Topographic beach pro"les at the location of El Choncho village. A net retreat of 60 m of island
front between April 1993 and November 1997 is clearly seen.
The central part of the barrier was breached in June 1996, during an exceptionally
high tide. The island was incised by a small channel, 5 m wide and less than 1 m deep,
located just beside the northernmost house of the village. The channel grew rapidly
with each high tide and by December of that year it became a true inlet, 30 m wide and
several meters deep. By May 1997 the inlet had migrated to the south and had a width
of 50 m and a depth of 10 m. Strong bi-directional tidal circulation deposited a large
ebb tidal delta in front of the inlet, and sand drift to the south of the island became
even more disrupted. In December 1997, #ooding along the central part of El
Choncho destroyed several houses and by February 1998 the area where the village
was located was completely underwater. From May to December the equatorial
Paci"c coast was under the in#uence of El Nino with sea level 30}35 cm higher than
normal (Fig. 4). The high sea level was responsible for the #ooding, as well as the
accelerated erosion and the rapid migration on the inlet [12].
5. De5nitive relocation
Between 1970 and 1988, El Choncho's agricultural land and the majority of the
summer homes had been gradually lost to beach erosion. During this period a "rst
relocation of the village took place to the island's interior. By 1992, El Choncho's
economy had deteriorated to the point where all the food had to be imported and the
only sources of income were "shing and timber. Timber activities had become
increasingly di$cult because of over-exploitation and new environmental regulations.
At this time some people left the island seeking new opportunities elsewhere.
From the date the barrier was breached, June 1996, islanders realized that reloca-
tion was absolutely necessary but the process did not take place immediately because
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I.D. Correa, J.L. Gonzalez /Ocean & Coastal Management 43 (2000) 51}64 59
Fig. 8. Air view of the new El Choncho village 6 months after construction had started. Note the typical
vegetation and well drain sands from the beach ridge complex contrasting with surrounding tropical rain
forest and mangrove swamps. View is to the East.
of a combination of lack of consensus about the new site, the scarcity of economic
resources and the hope, by some, that the erosional trend would stop. At that time the
"rst option considered was to remain on the island and to move along-shore, either to
the NW, away from the direction of inlet migration, or to the SE, to a wider portion of
the island. By the beginning of February 1998, inlet migration and beach retreat
intensi"ed dramatically due to a combination of high tides and higher than normal
sea level, and the remaining homes that were still occupied were destroyed within two
days. The intensity of the #ooding and the rapid beach retreat made the community
change their mind and decide that the wisest option was to leave the island and
relocate at the interior of the delta, option considered so far as a secondary one.
Consensus was quickly reached to rebuilt on the nearest interior and sandy beach
ridge complex known as `Santa Barbara beachesa, 200 m inland of the original
location and across the tidal channel (Fig. 8). Not a!ected by marine erosion, the
`Santa BaHrbara beachesao!ered the nearest to the sea stable setting with access by
boat at any tide stage and soils with some possibilities for basic agriculture. The
reconstruction process started in mid-February and by August 1998 most families had
completed building their houses in the new village. The only governmental help
provided was construction materials and all the construction work was made solely
by them.
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60 I.D. Correa, J.L. Gonzalez /Ocean & Coastal Management 43 (2000) 51}64
6. Discussion
The El Choncho village relocation illustrates some typical e!ects of the extensive,
long-term shoreline erosion along the 700 km length low segments of barrier islands
along the Paci"c littoral of Colombia. This situation is most likely to continue and
worsen in the future because of a combination of factors including global sea level rise,
earthquake induced and or compactional subsidence, tsunamis and occasional higher
than normal sea levels associated with El Nino [12,14,18,19].
This is not, however, the most dramatic case along the Paci"c barrier islands of
Colombia, as evidenced by the earthquake/tsunami brutal destruction of San Juan de
la Costa on December 12, 1979, for which quantitative "gures of local and regional
subsidence were measured immediately following the earthquake: as much as 1.6 m of
sudden subsidence occurred along a 200 km segment of coastline and "gures of
50}60 cm were reported for localities 20 km inland from the coast [7,20]. That
subsidence dramatically augmented an already existing regional erosional trend on
the southern Paci"c coast of Colombia. Although no "gures of earthquake-related
subsidence exist for the north and central Paci"c coast, the case described here and the
testimonies of inhabitants of other erosion threatened villages strongly suggest that
erosional conditions have been triggered or accelerated by earthquake-generated
subsidence, as was the case for several villages to the north of the San Juan delta in
connection with the 1970 BahmHa Solano earthquake [21]. Erosional vulnerability of
barrier islands of the Paci"c littoral is increased during periods of El Nino which
raises sea level for several months. During the 1997}1998 El Nino, a 35 cm sea level
rise incremented erosion rates along the already erosive shores. In a complex physical
framework such as this, modelling the evolution of coastal areas and predicting
shoreline evolution trends is a giant task far from being accomplished.
Socioeconomic e!ects of barrier island erosion are short term and drastically
disrupt the modus-vivendi of islanders. The main economic advantage of living on the
widest barrier islands of the Paci"c coast is the possibility of being almost self-
su$cient in basic food resources and supporting a small economy with surplus goods.
The loss of coastal lands in recent decades has eliminated this possibility for many
barrier islands of the Paci"c coast, so islanders are more dependent on "shing and
timber exploitation. This last resource is however rapidly decreasing in view of the
absence of reforestation programs, they have to travel farther distances every day in
order to obtain timber and that causes displeasure by the inhabitants surrounding
those areas. Migration of barrier islands's inhabitants to large cities of the interior
re#ects in part the diminishing of resources both in and around the littoral zone, part
as a consequence of marine erosion. For a population composed mainly of blacks and
indians, lacking basic education, the prospects of living in such centers are far from
adequate.
The relocation process of El Choncho is to our knowledge unique along the Paci"c
coast, in the sense that the decision to relocate inland was taken by the community
when relocating on the barrier island was still possible. Such voluntary relocation has
not been the case in neighboring villages threatened by erosion. Examples on the San
Juan delta include the cases of Charambira and Togoroma, where inland relocation
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I.D. Correa, J.L. Gonzalez /Ocean & Coastal Management 43 (2000) 51}64 61
took place only after several along-shore relocations failed at a high cost in resources
and time. The recent history of San Juan de la Costa illustrates the extreme case:
immediately after the destruction of the village, the government promoted an inland
relocation which was undertaken. Within "ve years, islanders, unsatis"ed in the new
location, returned to the barrier, disregarding the previous disaster and increased risk.
Continued shoreline retreat created a situation similar to El Choncho, and during the
1997}1998 El Nino, the village had to be again relocated to the interior.
The decision to relocate on the mainland taken by the community of El Choncho
was not an easy one because the option of remaining on the barrier was driven by very
strong and diverse motivations, basically cultural factors established by nearly a cen-
tury of island occupation. Among other factors, living closest to the sea is strategically
important because:
EThe villagers know at any time the sea and weather conditions in order to plan
activities.
EThe possibility of having eye contact with "shing teams at a short distance o!shore
exists.
EBeing aware of travelers along the coast allows villagers to be or to demand
assistance in an emergency (there are no radio or telephone communications in the
El Choncho barrier island and adjacent areas).
EA minimum tourist infrastructure had been developed as a source of income; an
important alternative considering that the two main economic activities, "shing
and timber, were becoming increasingly di$cult.
EDirectly facing the sea takes advantage of the sea breeze for a more comfortable
climate and to keep malaria transmitting mosquitoes away.
People in the new village are adapting to their new living conditions. Basic
agriculture provides some help, but the Santa Barbara beaches are far from providing
the same agricultural possibilities as El Choncho barrier island did and tourism
income is now practically absent, reducing strongly the economical perspectives for
them. Help has been demanded from the government in order to obtain technical
training and modern means for increasing the "shing capacities, which has become the
main activity by now. Not having direct, visual contact with the sea has been
particularly di$cult for many of them and the feeling of isolation is common, specially
for women.
The example provides some of the basic facts and antecedents that Coastal Zone
Management will have to be consider in the future, when governmental agencies have
the capacity for planning and regulating the development of the Paci"c coast littoral
zones. In terms of immediate Coastal Zone Management priorities, it is obvious that
present shoreline erosional trends and tsunami risk along Colombia's Paci"c coast are
factors which strongly support inland relocation of littoral villages as soon as possible.
A systematic program of large scale geomorphologic mapping in search of appropri-
ate inland sites for relocation should be the "rst priority of concerned agencies.
To improve the socio-economical conditions of barrier island inhabitants of the
Paci"c littoral of Colombia is certainly the another priority faced by the Colombian
government. Appropriate relocation strategies are just the "rst steps in that direction.
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62 I.D. Correa, J.L. Gonzalez /Ocean & Coastal Management 43 (2000) 51}64
Acknowledgements
Acknowledgments are due to COLCIENCIAS and to the Interamerican
Development Bank for providing "nancial support for this research. This paper
presents preliminary results of the EAFIT University research project: Indicadores
GeomorfoloHgicos, SedimentoloHgicos y BioloHgicos del delta del rmHo San Juan, Litoral
PacmH"co Colombiano. Special thanks are also due to Dr. William Neal, for
reviewing and discussing the document and to the unknown reviewers of this
journal.
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64 I.D. Correa, J.L. Gonzalez /Ocean & Coastal Management 43 (2000) 51}64
... Dünya genelinde binlerce yerleşme doğal (deprem, tsunami, sel ve taşkınlar) ve beşeri nedenlerle (maden çıkarımı, baraj projeleri ve havalimanı inşaatları gibi) yer değiştirmiş ve bu yer değiştirme olayı çeşitli akademik çalışmalara konu olmuştur (Afolayan, 1987;Correa & Gonzalez, 2000;Badri vd., 2006;Lora-Wainwright, 2014;Yang vd., 2017;Young & Essex, 2019;Forsyth & Peise, 2021;Matti vd., 2023). Afolayan (1987) Afrika' da Sasa Yeniden Yerleşim Projesinde yerleşme sakinlerinin sosyo-ekonomik koşullarını ortaya koymuş, yerinden edilmeden önce ve sonra insanların algısı ve yeni çevrelerinde karşılaştıkları travmatik deneyimleri açıklamıştır. ...
... Afolayan (1987) Afrika' da Sasa Yeniden Yerleşim Projesinde yerleşme sakinlerinin sosyo-ekonomik koşullarını ortaya koymuş, yerinden edilmeden önce ve sonra insanların algısı ve yeni çevrelerinde karşılaştıkları travmatik deneyimleri açıklamıştır. Kolombiyanın pasifik kıyılarında kıyı erozyonu nedeniyle yer değiştiren kırsal yerleşmeleri konu alan Correa & Gonzalez (2000) bu yer değiştirme sürecini betimlemişler ve yörede jeomorfolojik haritalama programının yürütülmesi gerektiğini önermişlerdir. Badri vd. ...
... Thousands of settlements around the world have been relocated due to natural (earthquakes, tsunamis, floods and tsunamis) and human causes (such as mining, dam projects and airport construction) and this relocation event has been the subject of various academic studies (Afolayan, 1987;Correa & Gonzalez, 2000;Badri et al., 2006;Lora-Wainwright, 2014;Yang et al., 2017;Young & Essex, 2019;Forsyth & Peise, 2021;Matti et al., 2023). An evaluation of the aforementioned studies in the international literature reveals that the problems of relocated residents are addressed as well as settlement problems, but social problems are more prominent than people's perception, adaptation, place attachment and psychological states. ...
Article
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İnsanın yaşadığı yerdeki hatıra ve deneyimleri zamanla o yere karşı aidiyet duygusunu geliştirir. Böyle bir yerin/yerleşmenin yer değiştirme ihtimali ortaya çıkarsa bu durum insan davranış ve ilişkilerini nasıl etkiler? Yer değiştiren yerleşmeler özelinde bu davranış ve ilişkileri açıklayabilecek insan odaklı bir yaklaşım benimsenebilir mi? Bu araştırma sorularından hareketle çalışmanın amacı; yer değiştiren yerleşmelerle ilgili betimsel coğrafya çalışmalarından farklı olarak konunun bilimsel çerçevesini hümanist coğrafya perspektifinde ortaya koymaktır. Çalışmada, yönetmenliğini ve senaryosunu Ali Özel’in yaptığı ve 2019 yılında gösterime giren Bozkır filmi içerik yönünden analiz edilmiştir. Film, Konya’nın Hadim ilçesine bağlı Dedemli köyünün yer değiştirme sürecini konu almaktadır. Çalışmada öncelikle Bozkır filmi indirilmiş ve filmin transkripsiyonu yapılmıştır. Daha sonra yer değiştiren yerleşme konusunu hümanist perspektifle açıklayabilecek tema ve kodlar oluşturulmuştur. Tema ve kodlar, MAXQDA 2020 programında işlenmiş ve bu program yardımıyla belge portreleri ve kelime bulutu hazırlanmıştır. İçerik analizleri, filmde yere bağlılık ve kabullenme temalarının diğer temalardan çok daha baskın olduğunu ve filmin bu temalar arasındaki çatışmalarla şekillendiğini göstermiştir. Çalışmanın bulguları; yerleşmelerin yer değiştirme süreçlerinde bu sürecin baş aktörü olan insanın düşünce, duygu, davranış ve beklentilerinin asla görmezden gelinmemesi gerektiğini ortaya koymuştur.
... Haasnoot et al. [93] in their discussion on various measures to be taken for coastal retreats have pointed out the need for awareness of the sea level rise and the requirement for the development of satisfactory policies for the retreat process with its proper execution. Correa and Gonzalez [94] have explained the retreat or relocation process of El Choncho island village located on the Colombian Pacific coast by 200 m landward in 1997. Similar efforts have been initiated in the Satabhaya village of Kendrapara district to relocate 118 families. ...
Article
With the changing climatic and anthropogenic conditions, the natural ecosystem especially the coastal zones is at great risk. The ocean is engulfing the land through the process of coastal erosion and this is becoming a great threat to coastal communities by forcing them to relocate from their homes and destroying their livelihoods. This study has tried to use machine learning algorithms for the first time to find the probability of the vulnerability associated with this hazard along the coast of Odisha state of India using a total of 32 factors involving environmental and socio-economic conditions. A total of 2500 locations have been used to create support vector machine (SVM), random forest (RF), shallow neural network (SNN), deep neural network (DNN), and convolutional neural network (CNN) models. Various accuracy metrics have been calculated which showed the RF model outperformed all with an accuracy score of 0.96. This is followed by CNN (0.93), DNN (0.91), SVM (0.88), and SNN (0.88). Further, to find the impact of all the factors in the model sensitivity analysis has been performed. Factor importance analysis by RF has been performed at state and district levels to understand the influence of various parameters in this disaster. This novel method will broaden the approach which we use to analyze this calamity and serve as an aid in the decision-making process of the concerned authorities.
... Despite El Choncho community initiating and driving the relocation process, overall outcomes were negative. In this case, the government provided only construction materials 43 to the community. A conceptual model of stakeholder interactions suggests that cases with 'mutual agreement' between community members and external actors generally face fewer obstacles than 'self-reliant' communities 5 . ...
Article
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The planned relocation of entire communities to less hazard-exposed destinations is an increasingly salient climate change adaptation strategy but often results in maladaptive livelihood outcomes. There needs to be understanding of how planning decisions affect outcomes—relocated people’s access to sustainable livelihoods, including physical, economic, natural, human, social and cultural assets. Here, drawing on data from 14 completed flood-related relocation cases, we use fuzzy-set qualitative comparative analysis and find that planning decisions, alone and taken together, contributed to sustainable livelihood outcomes. Relocation processes initiated and driven by community members had better outcomes than government-driven processes, adding a global comparative perspective to prior findings. Speed and transfer dynamics were also critical, with different implications for small and large communities. As a result, multiple pathways of planning decisions can lead to better outcomes, highlighting potential entry points for policy to promote more sustainable and people-centred planned relocation.
... However, in Juanchaco, some fishers specialized and intensified, while in Ladrilleros, even fewer households continued fishing and most of them did so only occasionally. This difference was primarily due to limited access to the fishery in Ladrilleros, caused by coastal erosion following the 1997-1998 El Niño [see 86,87] that forced the community to relocate from the beach to the adjacent coastal bluffs. Since fishers traditionally stored their boats on the beach, this significantly reduced opportunity in the fishery. ...
Article
Tourism and small-scale fisheries are two of the most important economic sectors in coastal areas around the world, yet the impact of tourism development on fisheries is understudied within the SSF literature. Studies have documented various aspects of tourism-fishery interactions, but it is not clear how they combine to impact total fishing pressure. The addition of alternative livelihoods is widely expected to alleviate pressure on fisheries resources, yet rural development transitions often accelerate exploitation of natural resources. This paper analyzes how tourism development impacts community-level fishing pressure through a comparative case study of fishing behavior and livelihood engagement in seven neighboring fishing communities in the Colombian Pacific, using space-for-time substitution to estimate change over time. Findings indicate that while tourism development leads to a decline in fishery participation, this decline can be more than offset by increases in fishing effort and improvements in fishing methods. This is related to an overall pattern of livelihood specialization and intensification that results in a divergence of household-level fishing behavior – between those that exit the fishery and those that fish more intensively – and an increase in community-wide fishing pressure. However, impacts vary from place to place due to contextual factors in the biophysical environment and socio-political systems that shape how tourism development affects fishing behavior and whether or not it is likely to benefit sustainable small-scale fisheries. These findings can be used to support place-based assessments in order to anticipate impacts, proactively design fisheries management, and inform more sustainable tourism development planning.
... These factors often result in coastal protection strategies such as beach nourishment and the construction of seawalls as a last line of defence (Tomlinson et al., 2016;Sinay and Carter, 2020;Toimil et al., 2020). In some cases, severe erosion has led to the relocation of residents (Correa and Gonzalez, 2000;Abel et al., 2011). Climate change projections (Pörtner et al., 2019) are predicted to affect the future wave climate (Hemer et al., 2013;Wang et al., 2014;Camus et al., 2017;Young and Ribal, 2019) which has the potential to further impact coastal areas (Ranasinghe, 2016) due to anticipated changes in longshore sediment transport (e.g. ...
Article
Multipurpose Artificial Reefs (MPARs) are structures that may provide aesthetically acceptable coastal protection and improve recreational outcomes. Twenty years after construction of the first MPAR, Narrowneck Reef on the Gold Coast of Australia, most of the available literature is still focused on the planning, design and construction of such structures and peer-reviewed publications on their post-construction monitoring, interaction with sediment transport and impacts on coastal morphology are lacking. The aim of this paper is to evaluate how does Narrowneck Reef influence the sediment transport, and morphological changes around the anthropogenic structure, two decades after construction. To do so, a combination of ten high spatial resolution topo-bathymetric surveys from the top of the dune to the 10 m depth captured over 21 months and a series of 60 simulations using a calibrated numerical model were used. Our results demonstrate that: although not expected during design or reported in similar structures, sand can bypass the MPAR around its offshore end; under oblique waves, the longshore currents are deflected as they pass the reef, resulting in a shadow zone on the downdrift side where sand deposits; the bar crest tends to be higher on the reef's updrift side compared to downdrift, indicating that the MPAR can act as a store for sediments, as initially designed. Furthermore, the MPAR can act to stabilise the bar as it moves onshore with a downdrift offset of the inner bar as a result of low oblique wave incidence. The results presented here demonstrate that the short-term response to the MPAR twenty years after construction is more closely related to the updrift build up of sand and the deflection of longshore currents as they encounter the reef than to the dissipation of wave energy. This is because MPARs are designed to dissipate just enough wave energy so that they can achieve their recreational goal (surfing).
... Silva et al., 2020Silva et al., , 2021 and climate change (Ranasinghe, 2016). Many coastal cities have been exposed to these factors and while some regions have decided to retreat (Correa and Gonzalez, 2000), in most areas accommodating and protecting coastal assets and infrastructure remain the preferred option (Tomlinson and Jackson, 2019). ...
Article
Implementing coastal protection strategies presents challenges for coastal managers, particularly in the absence of data driven historical learnings. These challenges are expected to increase with the growing pressures of urbanisation on the coastline and potential impacts of climate change. In an operational setting, where decision making needs to be undertaken in a timely and costly manner, while achieving the best possible outcomes, decision support tools serve an important role. This paper presents a framework for developing a decision support tool to support coastal protection, in particular sand resource management. The framework was developed in a partnership between a local government authority and academia and will be implemented to manage beach nourishments via a sand-backpassing decision support tool. To apply the framework and develop the tool, a calibrated numerical model was used to simulate a series of potential scenarios of dispersion of sand placement that include different wave conditions, initial beach profile condition (e.g. eroded, accreted, average) and volume of sand to be placed at three separate beach locations. The user can weight the relative importance of each location as well as the dispersion rates and beach state to rank the preferred location to place the sand for the best outcome. Here, we demonstrate the importance of the feedback process between beach morphology evolution, incoming waves and the volume of the nourishment on the evolution and dispersion of the sand placement. Moreover, by using the tool the user can identify the best locations to place the sand supporting operational sand management decision making by the local government authority. The framework presented here is flexible and can be used and adapted for other locations and applications where the morphodynamic feedback is important in predicting the lifetime of a sand management strategy. Finally, the importance of the engagement between academia and government for the development of effective coastal protection strategies is demonstrated and highly encouraged.
... Maladaptation can also be directly linked with voluntary resettlement, as resettlement always fails when people do not want to relocate, which inherently decreases their capacity to adapt and increases vulnerability (Barnett and O'Neill 2012). Correa and Gonzalez (2000) contend that resettlements to similar geographical regions can cause an increase in vulnerability and economic losses, and in case of involuntary relocation to these regions people tend to return to their original lands. Ganapati and Ganapati (2008) discuss public participation in resettlements and declare that although such participation may in theory be desirable, achieving it in reality proves to be more complicated. ...
Chapter
Flooding is the most frequently occurring disaster in the world. In recent decades, climate change has been shown to be linked to a higher frequency of flood occurrences around the world. Every year, flooding displaces millions of people worldwide resulting in escalating vulnerabilities of exposed populations. Pakistan, in particular, is extremely vulnerable to climate change induced floods. It has seen a growing trend of disastrous flooding events in recent decades. The extreme flood event of 2010 (and similar events in the years since) have caused tremendous human and material losses. The construction of ‘model villages’ as a mitigating strategy to flooding has turned out to be an intervention of choice for both public and private sectors for the resettlement of exposed and vulnerable population. This strategy was initiated by the government, and then various non-government organizations (NGOs) followed suit with their own planning and development approaches. More than 200 model villages have been developed in Punjab province since the 2010 flood event. This book chapter revisits the model villages developed in 2011 to evaluate public and private intervention in the aftermath of the flooding and assess their resettlement approaches. For this purpose, four model villages were randomly selected in severely flood-affected districts of Punjab province. Two of the studied model villages were developed by NGOs, while the other two were developed by the provincial government’s disaster management authority. Expert interviews, focus group discussions, authors’ observations, and household surveys were conducted. A total of 145 relocated households were surveyed using structured questionnaires. The analysis shows model villages designed and developed by NGOs were more sustainable and resilient than the resettled communities in provincial government backed projects. It was found that livelihood and skill-development programs based on local markets, community mobilization, training, maintenance and operation of community services, and young and adult literacy programs were the predominant factors which made communities more resilient.
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The planned relocation of entire communities to less hazard-exposed destinations is an increasingly salient climate change adaptation strategy, yet often results in maladaptive livelihood outcomes. Drawing on data from fourteen completed flood-related relocation cases, we assessed planning decisions (community engagement, site distance, scale, speed, and transfer dynamics) and outcomes in terms of changes to relocated people’s access to physical, economic, natural, human, social, and cultural assets. Through fuzzy-set qualitative comparative analysis, we investigated how such decisions, alone and taken together, contributed to sustainable livelihood outcomes. We find that relocation processes initiated and driven by community members had better outcomes than government driven processes. Speed and transfer dynamics were also critical, although varied for small and large communities. As a result, multiple pathways of planning decisions can lead to improved outcomes, highlighting potential entry points for policy to promote more sustainable and people-centered planned relocation.
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This article analyses the vulnerability conditions of a fishing community facing the extreme meteorological phenomena aggravated by climate change. The methodology is qualitative, supported by geographic methods, based on the case study of the “La Barra afro-descendant community”, located in the Colombian Pacific Coast, in the mouth of San Juan River. As there is limited access to the community due to its geographical conditions, besides the biosecurity requirements due to the COVID-19 pandemic, a documentary analysis, as well as multi-temporal maps based on satellite images, show the spatial changes on the coastline of La Barra, during the years 2001, 2011 and 2019. In addition to the above, interviews with academic experts and community residents are conducted. The term “vulnerability” is understood from the school of thought of climate change science and adaptation research. It is concluded that the vulnerability not only depends on climatic stimuli but also on the racialized and marginalized conditions of Afro populations located in isolated rural territories. In that way, the social and political nature of the meteorological phenomena could transform them in catastrophic events for vulnerable populations.
Article
Problem, research strategy, and findings Disasters displace millions of people every year. After the disaster, they must decide whether to return to their homes or move elsewhere. Planners and government officials often propose permanent relocation as a response. But relocations disrupt lives and livelihoods of households and communities and are therefore rarely the preferred option of those affected. Nevertheless, relocations happen, and planners often develop relocation policies and plan the move. We examined the dynamics of the relocation process through a conceptual framework consisting of five interrelated elements: 1) the natural science; 2) the risk decision; 3) the community’s relationship to place; 4) the relocation process, land, and money; and 5) the historical, social, and political context. This research draws from analyses of 53 cases of community relocation, including many that we have directly researched or worked on. Here we introduce this framework as a way for planners to systematically approach the task of evaluating and implementing proposed disaster-induced relocations. Takeaway for practice In planning for relocation, planners should work with all stakeholders to evaluate the risks, balance the risks of staying against those of relocation, and consider alternatives to complete relocation. Finally, planners should be astute regarding the broader contexts of relocation proposals.
Thesis
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Coastal geomorphology of the Pacific Coast of Colombia is interpreted in function of its geology and general climatic and oceanograpyical parameters. Geomorphological maps based in visual interpretation of IGAG - INTERA georeferentiated radar images produced in 1992 and of aerial photographs of ICAC. First tome: texts
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Southwestern Colombia and northern Ecuador were shaken by a shal-low-focus earthquake on 12 December 1979. The magnitude 8 shock, located near Tumaco, Colombia, was the largest in northwestern South America since 1942 and had been forecast to fill a seismic gap. Thrust faulting occurred on a 280- by 130-kilometer rectangular patch of a subduction zone that dips east beneath the Pacific coast of Colombia. A 200-kilometer stretch of the coast tectonically subsided as much as 1.6 meters; uplift occurred offshore on the continental slope. A tsunami swept inland immediately after the earthquake. Ground shaking (intensity VI to IX) caused many buildings to collapse and generated liquefaction in sand fills and in Holocene beach, lagoonal, and fluvial deposits.
Article
Precambrian, Paleozoic, and Mesozoic(?) metamorphic rocks form the basement of the central Colombian Andes, which was intruded by Mesozoic quartz diorite batholiths and was the site of Tertiary volcanism. Mesozoic miogeosynclinal rocks are preserved to the east in the Magdalena Valley, and eugeosynclinal rocks are preserved on the west flank of the Cordillera Central. The Cordillera Occidental includes highly deformed rocks of the Mesozoic eugeosyncline, intruded by Tertiary(?) dioritic to granitic plutons and overlain locally by Tertiary volcanic rocks. The fault-bordered Cauca Valley separates these two Andean ranges and was the site of deposition of fluviatile, lacustrine, and volcanic Tertiary rocks. Thick sequences of marine Tertiary sedimentary rocks occupy the Atrato-San Juan basin to the west and the Sinu-Uraba basin at the northern end of the Andes. Pillow basalts, gabbros, and andesites, are the chief rocks forming the basement complex of the Serrania de Baudo along the Pacific coast of Colombia. Bouguer anomalies attain values as high as + 135 mgals over pillow basalts and gabbros of the Serrania de Baudo. A negative anomaly with values as low as - 90 mgals is found over the Atrato-San Juan basin. Values increase to +95 mgals over the Sautata arch and then decrease to -45 mgals over the Sinu-Uraba basin. Bouguer anomalies are negative along the Cordillera Occidental southward from Mutata to near lat 5° N., but there the values become positive. These positive values are a southeastern continuation of the gravity high over the Sautata arch, and they persist southward along the Cordillera, despite topographic elevations greater than 3,000 m, which indicates an isostatic imbalance in the crust or upper mantle. This anomaly, the West Colombian gravity high, extends southward into Ecuador. Bouguer anomalies are negative (-20 to -150 mgals) over the Cauca Valley, Cordillera Central, and Magdalena Valley. These regional relations indicate that granitic crust is present under the Cordillera Central but may be thin or absent beneath the Mesozoic eugeosyncline. Mafic, perhaps oceanic, crust serves as floor of the Mesozoic eugeosyncline, the Pacific Lowlands, and the Serrania de Baudo. If an oceanic crust of 16 km is assumed in the Pacific area, west of the Colombian coast, the gravity data indicate an eastward increase in crustal thickness to 30 or 35 km beneath the Cordillera Central and Magdalena Valley. Major tectonic boundaries may be inferred from gravity data as follows: (1) Steep marginal gravity gradients suggest that the Atrato-San Juan basin is like a gigantic graben. (2) Steep gradients on the flanks of the Suatata arch suggest that it is a horst-like feature. (3) Rocks of the Mesozoic-early Tertiary eugeosyncline may locally override the mafic rocks that cause the West Colombian gravity high. (4) Steep gradients on the east side of this high mark the boundary between granitic crust to the east and oceanic crust to the west. South of lat 5° N., this zone coincides with the great Romeral-Cauca fault system. The Mesozoic eugeosyncline is interpreted to be the site of Mesozoic underflow of the Pacific plate beneath nuclear South America; the Romeral fault, with associated serpentinites, is the trace of a Mesozoic Benioff zone. The Atrato-San Juan basin may represent a Tertiary zone of underflow that was an early branch of the Peru-Chile trench. From analysis of regional distribution of earthquakes and focal depths in northern South America and vicinity it is concluded that relative motion between the South American plate and the Pacific plate is partitioned into two types: (1) some underthrusting occurs along the northern extension of the Peru-Chile trench, and (2) right-lateral movement occurs along the Dolores-Bocon6-El Pilar megashears. The western Cordillera of northern Ecuador and Colombia and eastern Panama are semiattached to the Pacific plate and have an east to northeast motion related to eastern spreading from the East Pacific rise and northward spreading along the Galapagos rift zone. Thus, gross relative motion of northern nuclear South America is counterclockwise with respect to the Pacific plate, Panama, and the Caribbean plate.
Article
In terms of the gross first-order effects of plate tectonics, there appear to be three major classes of coasts and several subclasses, depending upon their position relative to the moving plates of the tectosphere: (1) collision coasts, that is, those on the collision edge of continents and island arcs; (2) trailing-edge coasts, that is, those on the trailing edge or noncollision side of a continent; and, (3) marginal sea coasts protected by island arcs. The trailing-edge coasts range in form from the tectonically new coasts facing beginning separation centers to the morphologically active coasts bordering the debris plains formed from the erosion products of the continents. The good coherence between certain morphologic and tectonic features of coasts was used as a guide in formulating a purely morphologic classification with tectonic implications. The morphologic classification is defined simply in terms of the width of the continental shelf and the relief of the adjacent land forms: (1) mountainous coa...
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Five genetic island groups are identified: two groups associated with straight stretches of coastal lowland and three delta lobe groups (Rio San Juan, Rio Patia, and Rio Nira deltas). A few of the islands formed due to split detachment. Initially the islands were probably transgressive, then became regressive for an indeterminate period before recent reinitiation of a transgressive phase, and severe island front erosion. Many of the islands are sand starved due to sediment supply loss when distributary switching occurred, or because they are in areas with little sand in the associated mangrove substrate and no fluvial sand supply. -from Authors
Terremotos Colombianos, noviembre 23 y diciembre 12 de 1979
  • Ramirez Je Goberna
  • Jr
Ramirez JE, Goberna JR. Terremotos Colombianos, noviembre 23 y diciembre 12 de 1979. Informe preliminar Instituto. GeofmH sico de los Andes: Sismologia, 1980. p. 45:95.
Mapa Geologico de Colombia. Memoria explicativa, Ingeominas
  • H Gonzah Lez
  • Nun Ez
  • A Paris
GonzaH lez H, Nun ez, A, Paris G. Mapa Geologico de Colombia. Memoria explicativa, Ingeominas, 1988. 71pp.