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The 1999 Vargas tragedy was a disaster that struck the Vargas State a coastal region in the north of
Venezuela on 15 December 1999
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What is a mud- flow?
Heavy rainfall, snowmelt, or high levels of ground water flowing through cracked bedrock may
trigger a movement of soil or sediments
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1
cm of rain (approximately one
year's total rainfall for the
region)
As a result mudslides,
landslides poured down the
Caracas hillside
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High population density,
70% of Venezuela were
living in this small
coastal strip
Low economic area

in the ground becoming saturated on the hills of Caracas leading
to mudslides
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The slopes around the region were changed
to accommodate vast squatter settlements
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This meant as the ground
became increasing water logged it started to move under gravity down the slope resulting in the
buildings on top sliding as well
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For example the squatter settlements
increased the impact of the mudslides and landslides as the building material caused further damage
to human life such as people being crushed or injured by debris
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These out-ofseason rains formed when a cold front interacted with a moist southwesterly flow in the
Pacific Ocean
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In a 52-hour span during 14, 15 and 16 December 1999, 91
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These
heavy rains included 7
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This increased amount of surface run- off eroded the soil resulting in it dislodging
and being transported down the Caraballeda fan
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The intense rainfall decreased the water’s
lag time
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The time between landing (rain onto ground) and it then reaching a basin or
river is reduced causing the river to reach its carrying capacity faster therefore water begins
to breach the banks, also known as flash flooding
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In Vargas’s case there was a short
amount of time between them
causing flash flooding
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Generally after this first wave of flooding, from the coast to just past the
crest of the Sierra de Avila, these rains triggered thousands of shallow landslides that stripped
soil and rock off of the landscape and sent them slipping down the mountainside
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In addition to these debris flows, flash floods carrying extremely high sediment loads were
very dangerous
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They incised new channels to depths of several meters into
every alluvial fan delta on the Vargas state coastline, and they blanketed these fans with
sediment
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Soils forming on
them are fine-grained, thin and often *colluvial
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Erosional processes such as abrasion wear away the soil beneath,
entraining loose material which then acts as an abrasive tool, scouring the bedrock as the
mudflow moves down the Caracas hillside
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Because *foliation planes are planes of weakness, these layers within the rocks strongly
influence landslide and debris flow hazard
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Therefore as the
water ran down the Venezuelan hillsides it chipped away the top layer of the bedrock by
abrasion which added to the mass mud flow which later caused not only damage to the
landscape but also the local community
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As such, many of them have been extensively developed and
urbanized
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As of 1999, several hundred thousand people lived in this narrow coastal strip in Vargas
state
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In the Caracas metropolitan area, about 80 percent of the population was impoverished in the
late 1990s
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These homes, called ranchos, were illegal and known to be dangerous
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This poor planning by the local authorities
resulted in thousands of people building poor quality homes across the hillsides of Caracas,
putting them in direct danger if a hazardous event was to happen
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The shade also allows
the soil to stay moist enabling it to absorb and drain water
running down the hill slope
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This means during heavy
rain periods the soil is easily washed away and entrained by
the flowing water accumulating to form a mudflow
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This has meant a
large number of make- shift homes have been built, often
to a poor standard such as using iron sheets and scrap
wood boards they can find
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The debris from the homes then
went on to act as a destructive tool further down the hill,
knocking down more homes and building in strength
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This increased the unemployment in the area meaning less income therefore reducing a
family’s quality of life as they may no longer be able to afford healthcare or education
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This loss in income means less money available to spend on the
local community, for example re- building homes or infrastructure
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The disaster was of such
magnitude that the president of the Red Cross initially presumed more than 50,000 dead
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After the disaster, Venezuelan President Hugo Chávez advocated for other Venezuelans to
open up their homes, and "adopt a family"
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Chavez refused the help of United States soldiers in handling the emergency situation, even
though the arrangements had been made and U
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Navy ships had been already dispatched
with men, heavy machines, and aid supplies
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Over 8000 residences and 700 apartment
buildings were destroyed in Vargas
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Chavez refusing help from the US pro- longed the
recovery of the area as Vargas was already a low developed and poor area
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Lack of communication between government officials, relief organizations and emergency
personnel led to chaos in the aftermath of the mudslides
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This caused
even more havoc amongst the people as no plan had been made to cope with such a disaster
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Donations were lost because there was nobody to track them therefore this lost money could
no longer be spent on helping the people in need causing further suffering and chaos
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Creating
infrastructure that can withstand torrential rains and landslides is essential in this part of
Venezuela as it is prone to landslides due to the steep slopes
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Nine years after the event, thousands
remained homeless highlighting the
government’s flaws in its response
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The government quickly moved its focus to what caused the mudslides instead of dealing
with the impacts
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This resulted in a high population density
all with minimal housing which in turn created a mass death toll of about 25,000
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In this case I believe despite the heavy rainfalls being the prime cause, the illprepared population followed by an unorganised government made the impacts a lot worse
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People lacked
the education on how to react to a disaster which caused them to panic creating chaos across
the Vargas State
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Town planning, such as
allocating certain areas where no buildings could be built due to its risk factor would save
lives and reduce costs in re- building homes
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