living with natural hazards: jamaica - united nations development

Living with NaturalHazards: Jamaica

GENERAL INFORMATION

� Implementing Institution: Unit for Disaster Studies,Department of Geography and Geology, University of the WestIndies (UWI)

� Head: Rafi Ahmad

� Details of Institution: Address: Unit for Disaster Studies, Department of Geography andGeology, University of the West Indies, Mona, Kingston 7, Jamaica

Tel.: (+876) 927 2129, 2728

Fax: (+876) 977 6029

E-mail: [email protected]

Website: www.mona.uwi.edu/uds

� Implementation Period: The initiative began in 1991 and is ongoing.

� Costs: The Unit for Disaster Studies does not receive any dedicatedfinancial support and has no budget to support its activities. It hasreceived two grants from the Caribbean Disaster Mitigation Projectof the United States Agency for International Development (USAID)and the Organization of American States (OAS): one grant ofUS$60,000, awarded in 1996, and a second grant of US$35,000. TheUnit for Disaster Studies has also obtained funding from varioussources for other critical activities.

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70 VOLUME 12: EXAMPLES OF NATURAL DISASTER MITIGATION IN SMALL ISLAND DEVELOPING STATES

SUMMARY

Land use in Jamaica is changing rapidly inorder to meet the economic and housingneeds of the growing population. The high incidence of hydrogeologicaldisasters in the last decade, includinglandslides and flooding, is symptomaticof this change (see table 1).

The project, “Living with NaturalHazards in Jamaica”, is a proactiveresponse to managing the risks posed bysuch natural hazards. Although focusedon Jamaica, this initiative is designed toserve the entire Caribbean region, withthe aim of demonstrating the importanceof geological knowledge to forecast,avoid and mitigate natural hazards insmall island developing States (SIDS).

The important elements of the project are:

• a website: Geology for NaturalHazard Loss-reduction andEnvironmental Management in theCaribbean (see www.mona.uwi.edu/uds).The main purpose of thisCaribbean-focused website is toprovide scientific information, datasources and references that willenable a better understanding of theactive processes leading to naturaldisasters and how people interactwith their environment;

• a four-week summer trainingcourse on “Analysis andManagement of Natural Hazardsand Risks” (see www.mona.uwi.edu/uds/GEOHAZARDS_2001/GEOHAZ2001-CONTENTS.html)

geared towards students and disaster professionals from withinand beyond the Caribbean region;

• research into natural hazards, particularly landslide processes,neotectonics (a technique used topredict earthquakes that involvesmeasuring the rate of slippage of landmarks along faults) and sediment-water flooding andcoastal-water flooding;

• the rapid assessment of natural disaster events;

• the publication and presentation of research results in scientific jour-nals and at local, regional and inter-national conferences and seminarsand, based on this research, thepreparation of hazard maps; and

• the presentation of research findingsin magazines and other news media.

BACKGROUND

AND JU S T I F I C AT I ON

Until 1986, the village of Preston in theParish of St. Mary, north of the capital city,Kingston, was an active farming communi-ty. Slope movements in and around the vil-lage following heavy rainfall during Mayand June of that year caused the wide-spread development of fissures, slumpingand subsidence, forcing residents to aban-don their homes and farmland. Today,Preston is a ghost town. The overall publicreaction to this event was perhaps bestsummed up in an editorial in the leadingnewspaper of Jamaica, the Daily Gleaner, of18 May 1986, which described it as the “St.

Living with Natural Hazards: Jamaica 71

Mary Mystery”, suggesting that there wasno explanation for this phenomenon.However, the causes of this misfortune forthe residents of Preston were landslides,which are an all-too-real and common geo-logical hazard not only in Jamaica but alsoin the wider Caribbean.

In Jamaica, Preston is not the onlyplace that has been affected by landslidesin recent years. The rainstorm of 3-4January 1998, for example, triggeredwidespread landslides and related flood-ing in the Rio Grande Valley of Portland

in the northeast of the island, resulting indirect losses estimated by the NationalEnvironment and Planning Agency (NEPA)and the Office of Disaster Preparedness andEmergency Management (ODPEM) atsome US$8 million.

The frequency of such hydrogeolog-ical natural hazard events in Jamaica,approximately one in every four yearsduring the last 50 years, makes it abun-dantly clear that natural hazard events arewidespread and costly (table 1).

Event Damage (estimated cost in US$)

Flood rains Cost of repairs to damaged and destroyed road May-June 1986 network: US$16 million.

Village of Preston, St. Mary, destroyed; 17 families displaced; replacement cost in 1986: US$273,000.

Hurricane Gilbert Approximately 60 per cent of the island water facilities 8-19 September 1988 damaged; repair costs estimated at US$10 million.

Boar River water supply pipeline damaged.

Repairs to island road network estimated at US$19.3 million.

478 landslides along 108 km of roads in northwestern St. Andrew (4 per cent of the total road system of the island) blocked by landslides.

Landslides delivered an estimated 20,000 m3 of sediment to rivers.

Flood rains Island-wide damage estimated at US$30 million.21-22 May 1991 Bog Walk Gorge road blocked by a landslide, forcing

it to remain closed for more than six months.

Tropical storm Gordon Approximately 241 km, or 2.3 per cent of the total 11-12 November 1994 road network of Jamaica, damaged; cost: US$2 million.

Damage to water systems estimated at $834,000.

Flood rains Total damage approximately US$8 million.3-4 January 1998Portland

Period from 1986 to 1998 Total: Approximately US$86.25 million

Table 1 Damage to infrastructure caused by some of the landslide and floodingevents occurring during the period from 1986 to 1998 in Jamaica.


The vulnerability of Jamaica to multi-ple hazards is one of the main threats tothe sustainable development of the coun-try. However, this situation could beavoided because the causes of the major-ity of natural hazards occurring inJamaica are relatively well understood.

The high incidence of natural hazards in Jamaica is caused by a combi-nation of geological, geophysical andgeographical factors (table 2). For exam-ple, the island is located in the track ofAtlantic hurricanes and also within a seis-mically active plate boundary zone.Geologically young landforms with steephillsides are characteristic. As a conse-quence, the hazards that affect the islandmost frequently are landslides and flood-ing. These hazards are important becauseof their frequency, associated loss of life,disruption of socio-economic activitiesand their effect on the built and naturalenvironment. Landslides account formost of the natural disasters that haveoccurred on the island during the lastdecade and continue to present risks tolife and property (fig. 1). The high incidence of landslides and flooding isalso symptomatic of changing land use.

In Jamaica, landslides and floods are arecurring cause of death and injury andhave damaged and destroyed rural settle-ments, schools, public and private proper-ty, roads, bridges, culverts, retaining walls,agricultural land and crops, waterpipelines, electricity transmission linesand submarine cables. In addition, slopesthat have been denuded by landslides suf-fer from accelerated soil erosion. Theindirect economic costs of such natural

disasters, therefore, can be several ordersof magnitude higher than the direct costs.

Natural hazard events become natu-ral disasters when geological knowledgeis not sufficiently considered in policydecisions on land use and also partlybecause of poor communicationbetween experts, decision-makers, com-munities and individuals. Losses andrisks from recurrent natural hazardevents might be reduced and/or avoidedif scientific data on the physical envi-ronment in which people live were madeavailable freely and openly to all con-cerned. It is possible to predict naturalhazard events with a fair degree of relia-bility, a fact that makes natural hazardsamenable to measures directed at avoid-ance and/or prevention.

Societies need practical and timelyinformation that may help them to evalu-ate whether or not particular hazardsthreaten their lives, economic activitiesand property and to help them to decidehow to respond proactively to hazardoussituations.

When it comes to minimizing lossesfrom natural hazards, however, Jamaicacan be described as “data-rich but information-poor”. There is a great dealof environmental and geological dataavailable in scientific publications andreports but such information is not readilyavailable to land-use planners or thegeneral public. As a result, public fundsare often spent on re-investigating particular hazards.

Over the years, the Department ofGeography and Geology at UWI has


Geological Region

Limestone plateau Interior Coastal plainswith hills mountain ranges and marshlands

Bedrock Covers 693,000 ha or 64 per cent of the island, mainly in central and western areas.Composed of tertiary limestones with subordinate clastic rocks (i.e., made up of fragmented pieces of the original rock) that are extensively jointed and faulted.

Geomorphology Elevation between 700 and 1,000 m. Slopes greater than 25 degrees. Highly dissected.Karst topography and inland drainage. Fault scarps common. Average annual rainfall between 125 and 375 cm.

Soils 62 per cent of all the soils (maximum thickness are on limestone. about 1 m)

Susceptibility to Moderate to high.landslides triggeredby earthquakesor precipitation

Flooding Moderate to high. potential Alluvial fan flooding.

Seismic hazard Moderate to high, from plate depending on location.boundary zone

Landslide-related Moderate to high. erosion rates Approximate area affected:

685,000 ha.

Population 8density (people/ha)

Table 2 Summary of geology, geomorphology, soil and water resources,natural hazards and land use in Jamaica.

Covers 238,000 ha, or 22 per cent of the island, mainly in eastern and cen-tral areas. Cretaceous andTertiary volcaniclastic rocks,andesites, granodiorite and subordinate schists,limestones and serpentinites.Bedrock intensively jointed,faulted, altered and deeplyweathered.

Maximum elevation: 2,254 min the Blue Mountains. Highlydissected mountains formingthe core of the island. Fault-controlled valleys and faultscarps. Host to all the water-sheds on the island; manystreams and rivers. Slopesgreater than 30 degrees.Average annual rainfall: 190to 700 cm.

24 per cent of all soils.Residual soils.

Very high.

Very high. Alluvial fan flooding.

Moderate to high, depending on location.

Very high. Approximate areaaffected: 250,000 ha.

1.3: very low in theBlue Mountains.

Covers 152,000 ha, or 14 per cent of the island,mainly along the southerncoast, fringing the uplands.Quaternary sediments composed of unconsolidatedto poorly consolidated gravels, sands, silts and clays.

Alluvial fans; river valleydeposits; terraces; sanddunes; raised coral reefs; poljes (flat, fertile valleys in a karstic area); thePalisadoes tombolo, a flatarea composed of sedi-ments. Average annual rain-fall: 190 cm. The major popu-lation centres of Jamaica arecoastal cities.

14 per cent of all the soils.Transported soils.

Low.

Very high; subject to bothcoastal and riverine flooding.Alluvial fan flooding. Tsunamiand storm-surge hazard.

High; some areas subject toliquefaction. Tsunami hazard.

Low to moderate.Approximate area affected:120,000 ha.

More than 12.


made significant contributions to the science of hazards and this information hasbeen made available to the relevant agen-cies, including ODPEM and NEPA. In par-ticular, since 1986, systematic research hasbeen focused on the specific requirementsof ODPEM and the two agencies havesigned a memorandum of understanding tocooperate in natural hazards and disasterresearch programmes. The UWI Unit forDisaster Studies, established in 1991, col-laborates with these and other agenciesinvolved in environmental management.

DES C R I P T I ON

In 1991, the Unit for Disaster Studies wasestablished in the Department ofGeography and Geology at the Monacampus of the University of the WestIndies (UWI) as a focal point to promoteinterdisciplinary research on natural hazards and disasters. The Unit forDisaster Studies was conceptualized as along-term project and continues to this day.

Natural hazard management consistsof three well-defined activities: proactivemeasures, actions during and immediate-ly following an event, and post-disasteror reactive measures. The research andoutreach efforts of the UWI Unit forDisaster Studies are focused on proactivemeasures and include:

• investigation of hazardous processes,especially landslides, their extent,impact and significance;

• promotion of research;

• preparation of hazard zonationmaps that will form the basis forland-use planning;

• creation of a database using theGeographic Information System(GIS);

• training of local people to carryout independent investigations;

• advising on proactive responses tothe risk of landslides; and

• transfer of this information toODPEM, affected communitiesand the public.

Figure 1 Landslide inventory map of Jamaica.

Major TownsLandslidesRiversMain RoadParish

Caribbean Sea

0 12.5 25 50Km


To achieve these aims, the Unit forDisaster Studies has received two grantsfrom the Caribbean Disaster MitigationProject of the United States Agency forInternational Development (USAID) andthe Organization of American States(OAS). The first grant, of US$60,000,funded the preparation of landslide haz-ard zonation maps, manuals and userguides as well as a conference and fieldtrips to Kingston, Portmore and St.Andrew, Jamaica, while the second grant,of US$35,000, was used to create a web-site for the Unit for Disaster Studies, tocompile a natural hazard and disaster bib-liography for Jamaica and the Caribbeanfor the Caribbean Disaster InformationNetwork (CARDIN), to prepare coursemanuals for a summer course in geohaz-ards at UWI, Mona, and to deliver thefirst summer course on geohazards atUWI in June 2000. The Unit for DisasterStudies also obtained funding from various sources for other critical activities,including the preparation of landslide susceptibility maps for the Kingston metropolitan area.

The data required to develop proactive measures for mitigating natu-ral hazards rely on carrying out basicand applied research. For example, dataare obtained from such sources as scien-tific research papers, historical records,maps, formal and informal technicalreports, and newspaper articles. All this information is then combined togenerate hazard maps.

In order for these hazard maps to bemeaningful and acceptable to a wide

range of users in Jamaica – including entities at the community and nationallevels – the process used by the Unit forDisaster Studies to prepare hazard mapsfor Jamaica included:

• the establishment of a projectsteering committee with a mem-bership that included the sponsor,multisectoral representatives andpotential users, including non-governmental organizations, government agencies, privateinterests, civil engineers, plannersand disaster-preparedness agencies;

• drafting the terms of reference forthe project by the project steeringcommittee, which also monitoredthe progress of the project;

• submission of draft hazard maps and reports to the project steeringcommittee for review and comments;

• modification and appropriateamendment of the final hazardmaps that were prepared in bothdigital and multiple paper forms;

• preparation of guidelines for theuse of hazard maps and their limitations;

• presentation of hazard maps in a workshop and field visits todemonstrate how maps should beused; and

• promotion of maps and relatedproducts by local disaster andenvironmental management agencies for use in environmentalimpact assessments, loss-reductionstrategies and land-use planningregulations.


Although it may not be possible toeliminate hazardous processes altogether,the application of mitigation measurescan reduce their destructive affects onpeople, communities, infrastructure andproperty and prevent current hazardsfrom becoming future disasters. Hazardmitigation, therefore, must be a part of alldevelopment planning. In Jamaica, thisrequires an understanding and applica-tion of the knowledge of the island’s geol-ogy, geomorphology, hydrology, soils,and the geotechnical characteristics ofrocks and soils. Although there are somegaps, such data are abundantly availablefor Jamaica. Most of the baseline datahave been generated by the local earthscience and engineering communities,often with international collaboration.Local scientists and engineers, someworking with UWI, have the skills to uti-lize this existing knowledge, improveupon it and carry out basic geological-geomorphic mapping, hazard mapping,site investigations and laboratory testing.

In the 1990s, for example, the UWIUnit for Disaster Studies played a key rolein the successful completion of several nat-ural hazard mapping projects. As a resultof these projects, the Unit for DisasterStudies has created an online resource (seewww.uwimona.edu.jm/uds) for the dissemina-tion of natural hazard information.

TR A I N I N G CO U R S E

A four-week summer course at UWI,Mona, on “Analysis and Management of Natural Hazards and Risks”, first delivered in 2000, provides training on

understanding natural hazards, mappinghazards and use of hazard maps in theCaribbean. Being a regional university,the teaching of such courses at UWI,Mona, has proved to be an effectivemedium for promoting comprehensivedisaster management throughout theCaribbean. The online resource is inte-grated with the course and containscourse reading materials.

Among the subjects covered by thecourse work are the tectonic frameworkof the Caribbean, including plate bound-aries and active processes, and the inter-pretation of aerial photographs, includingtheir limitations and distortions that mayappear. Students are also taught how touse Geographic Information Systems(GISs) and, using Jamaica as an example,they learn how to develop conventionaltopographic maps and how to interpretlandslides and volcanic eruptions. As wellas specially designed lectures, studentswork on individual projects that providethem with vital hands-on experience. TheUnit for Disaster Studies website also listslinks to sites and agencies that provideinformation on specific geohazards thatare useful both during the course andafterwards when participants (such as stu-dents and disaster professionals from theCaribbean region) begin to apply theirknowledge in solving real-world problemsrelating to natural hazard loss-reductionactivities in their particular country.

HA Z A R D MA P S

The UWI Unit for Disaster Studies hascompiled a list of hazard maps available


for Jamaica. These maps have beenorganized into three groups (table 3):

• reference maps for hazard assessment;

• hazard maps; and

• GIS-based hazard maps preparedin the 1990s.

Map TypeReference maps for hazard assessment• Geological maps of the Kingston District, 1951;

• Bathymetric and tectonic maps, 1977;

• Jamaica geological map: Mines and Geology Division, 1977;

• Soil maps, 1985;

• Climate maps: National Atlas of Jamaica, Town Planning Department, 1989;

• Demographic, topographic, drainage, land-use, vegetation, lifeline and critical facilities maps: National Atlas of Jamaica, Town Planning Department, 1989;

• Topographic maps: National Land Agency, Surveys and Mapping Department;

• Vertical aerial photographs for stereo viewing: National Land Agency, Surveys and Mapping Department.

Hazard maps• Earthquake: Preliminary hazard assessment: Mines and Geology Division, 1987;

• Flood and landslide risk map - Hope River Valley, St. Andrew: Office of Disaster Preparedness and Emergency, 1987;

• Tropical cyclone: Preliminary hazard assessment: Mines and Geology Division, 1987;

• Yallahs River 100-year flood boundary: Office of Disaster Preparedness and Emergency Management, 1988;

• Landslide susceptibility map for Upper St. Andrew, Jamaica, 1992;

• Hope River flood plain map: Underground Water Authority, 1994;

• Rio Cobre flood plain maps, sheets 1 to 8: Underground Water Authority, 1994;

• Hydrogeological map of the Lower Yallahs Basin, 1997;

• Landslide susceptibility map for the Upper Rio Minho Watershed, Central Jamaica.

GIS-based hazard maps• Natural hazard maps for the 11 km land corridor lying inland from the south coast of Jamaica, roughlybetween Kingston in the east and Negril in the west: Technical Report no. 4, Geology and Natural Hazards, sec-tion 4, Natural Hazards, 1998;

• Kingston wind speed, flooding and storm surge hazard assessment: Caribbean Disaster Mitigation Project (seewww.oas.org/cdmp/document/reglstrm/index.htm);

• Montego Bay storm surge hazard assessment: Caribbean Disaster Mitigation Project (seewww.oas.org/cdmp/document/reglstrm/index.htm and www.oas.org/cdmp/document/reglstrm/Jamaica.ppt);

• Landslide susceptibility map, Rio Minho Catchment, Jamaica: UWI Unit for Disaster Studies, British Geological Survey, Department for International Development (United Kingdom), 2000 (see www.bgs.ac.uk/dfid-kar-geoscience/database/reports/bw/WC00010_BW.pdf);

• Kingston earthquake hazard assessment: Caribbean Disaster Mitigation Project (see www.oas.org/cdmp/document/kma/seismic/kma1.htm);

• Kingston multi-hazard assessment: Caribbean Disaster Mitigation Project (see www.oas.org/cdmp/publist.htm);

• Kingston landslide hazard assessment: UWI Unit for Disaster Studies and Caribbean Disaster Mitigation Project(see www.oas.org/cdmp/document/kma/landsl_4.htm, www.oas.org/cdmp/document/kma/landsl_5.htm andwww.oas.org/cdmp/document/kma/landslmap.htm.

Table 3 Natural hazard maps available for Jamaica.


Studies by scientists at the UWI Unitfor Disaster Studies have helped to identifythe controlling factors and mechanismsthat favour the occurrence of landslides inJamaica. These include triggering mecha-nisms such as earthquakes and heavy rain.Research has revealed that all earth-quakes with a magnitude of 4.5 or greateron the Richter scale have caused land-slides. In addition, 200 to 300 millimetresof rain falling within a 48-hour periodalso initiate shallow landslides that arequickly transformed into debris flows andmud flows that cause extensive damage.Landslides are also strongly influenced byrock type and geological structures, withthe density of faults and joints being veryimportant factors. Knowledge of thesefactors can now be used to mitigate landslide hazards.

As an example of how data can beinterpreted, figure 2 presents the results

of rainfall thresholds that initiate land-slides and sediment flooding. The thresh-old relation indicates that for rainfall ofshort duration, more than 36 millimetresof rain falling in one hour is likely to trig-ger landslides. Low average rainfall inten-sities of about 3 millimetres per hour,however, are sufficient to cause landslidesif the storm duration approaches approx-imately 100 hours. There is also a rela-tionship between the landslide character-istics and the position of the landslide-triggering storm on the threshold line.Storms near the short-duration/high-intensity end of the threshold line triggermostly shallow landslides by causingexcessive pore pressure in the weatheredbedrock. Such landslides were associatedwith storms that occurred in 2001 and2002. In contrast, storms near the long-duration/ low-intensity end of the thresh-old have triggered the largest, deepestlandslides, including those in eastern

Figure 2 Threshold for rainfall-induced landslides in easternJamaica, 1951-2002.

Rainfall Duration (hours)Rainfall events producing landslides (2001-2002)

Storms that did not cause landslides (1993-1999)

Rainfall that caused landslides (1951-1988)

Rainfall Intensity (m

m/hour)

1 10 100 10001

10

100


Jamaica, such as those triggered byHurricanes Flora (1963) and Gilbert(1988) and rainfall in 2001.

In order to improve hazard maps andlandslide prediction, scientists at theUWI Unit for Disaster Studies are cur-rently trying to establish the effects ofsoil-moisture conditions prior to the rain-fall event. It appears that these may notbe very significant in May or during theearly part of the hurricane season in latesummer. Rather, it is at the end of thehurricane season, in early winter, thatincreased soil moisture becomes important.Given that rainfall intensity can be accu-rately measured and that the timing ofmost landslides can be accurately ascer-tained, it is possible to establish fairlyrobust intensity-duration relationships.

Among the hazard maps produced bythe UWI Unit for Disaster Studies is alandslide hazard-mapping component ofthe Kingston Multi-hazard Assessmentunder the CDMP. Both landslide suscep-tibility maps and manuals are available at:www.oas.org/cdmp/publist.htm.

Following the successful completionof the Kingston Landslide SusceptibilityMapping Project, the Unit for DisasterStudies has established itself as an agencycapable of undertaking landslide hazardmapping and this has served as a platformfor the Unit to undertake other projectssuch as the Halcrow Project. TheHalcrow Project (Halcrow GroupLimited, London, United Kingdom)offered the UWI Unit for DisasterStudies an opportunity to prepare naturalhazard maps for the 11-kilometre stretch

of land that lies inland from the southcoast of Jamaica roughly betweenKingston in the east and Negril in thewest. In addition, landslide susceptibilitymaps were prepared for the Rio MinhoCatchment, Jamaica, as part of a collaborative project with the BritishGeological Survey and the Departmentfor International Development of theUnited Kingdom (DFID) (table 3).

The preparation of natural hazardmaps is a relatively new scientific disci-pline in the Caribbean. Therefore, hazardmap users have had little time to applyand test the maps and to provide themapmakers with the feedback that willimprove the products.

Furthermore, hazard maps are onlythe first step in the complicated chain ofthe perception of and response to naturalhazards by local communities and government agencies. Indeed, since thecompletion of the projects highlightedearlier, scientists at the UWI Unit forDisaster Studies have taken every avail-able opportunity to inform the generalpublic and Government planning agen-cies regarding the use of the hazard mapsin land-use planning. It is the elected andappointed Government officials, howev-er, who must make the decisions con-cerning the mitigation of natural hazardsand land use that best serve the interestsof the State and its people. Most likely,the actual decision-makers will not beearth scientists; they will thus need to bepersuaded as to the benefits of using nat-ural hazard maps and informed as to howdecisions can be guided by the informa-tion presented in the maps.


An inventory of natural hazards andhazard maps must be employed in riskevaluation, land-use planning and thedesign of engineering structures in orderto facilitate the implementation of strate-gies aimed at reducing losses caused bynatural disasters. Thanks, in part, to thework of the UWI Unit for DisasterStudies scientists, such natural hazardmaps of varying quality and scale are nowavailable for Jamaica. These maps are inthe public domain and are available freeof charge. In addition, manuals thataccompany hazard maps provide awealth of new data that may be readilyused for a variety of purposes and bydiverse users.

SE D I M E N T-WAT E R FL O W S

Debris flows, mud flows and debrisfloods, collectively known as sediment-water flows, frequently occur in small andsteep drainage basins following signifi-cant rainfall events. Sources of sedimentsinclude storm-induced landslides, loosesediments on slopes derived from oldslope failures, and sediments in the water-courses related to previous sediment-water floods. The mobilization potentialof these sediments is high and, in manycases, it is the deposition of sedimentsrather than water that leads to the hazardous situations.

Scientists at the UWI Unit forDisaster Studies have shown that disas-trous flood events occurring in Jamaicaare sediment-water flows rather than simple water floods, as was commonlyassumed (see “What we call flood inJamaica is important”, mona.uwi.edu/

cardin/virtual_library/docs/1131/1131.pdf,and “Sediment-water floods in theCaribbean”, www.mona.uwi.edu/cardin/virtual_library/docs/1133/1133.pdf).

Although direct and indirect lossesfrom recurring sediment disasters are inthe order of millions of Jamaican dollarsfor every event, this subject has notreceived the attention of either the scien-tific community or disaster managementofficials. Indeed, until now, all sediment-water flows have been recorded andtreated as water floods and most mitiga-tion is designed to contain water floods.

PAT EN T I NG AND

COMMERC I A L I Z AT I ON

The UWI Unit for Disaster Studies has apolicy of open access and makes all itsdata and maps available free of charge todecision-makers, the public and all otherinterested parties. To this end, theCaribbean Virtual Disaster Library hasbeen created in partnership with theCaribbean Disaster Information Networkat the library on the UWI campus atMona (see www.mona.uwi.edu/cardin/virtual_library/searchlibrary.asp).

PARTN E R SH I P S

Among the national and regional partnerswith which the UWI Unit for DisasterStudies collaborates are: the BritishGeological Survey, the Caribbean DisasterEmergency Response Agency, theCaribbean Disaster Information Network,


the Geological Society of Jamaica, theInternational Consortium on Landslides, theInternational Landslide Research Group, theJamaica Geographical Society, the NationalEnvironment and Planning Agency, theOffice of Disaster Preparedness andEmergency Management, the Organizationof American States and the United StatesAgency for International Development.

REP L I C A B I L I T Y

A detailed description of the contents ofthe four-week summer course, “Analysisand Management of Natural Hazards and Risks”, together with supportingmaterial, has been posted online atwww.mona.uwi.edu/uds. This allows for allinterested persons to adapt the course tosuit their needs. It is not known who hasused the model.

The course, which is open to bothundergraduate students and disaster pro-fessionals from within and beyond theCaribbean region, has proved popularand, over the past five years, some 71people have attended. It is hoped thatthose attending the course are now put-ting into practice in their own countrieswhat they learned during the course.

POL I C Y IMP L I C AT I ON S

The UWI Unit for Disaster Studies invitedpersonnel from the Town PlanningDepartment, Government of Jamaica, toparticipate in the dialogue on the use ofhazard maps in city planning. One out-

come of this interaction has been the prepa-ration of a document on landslide hazardinformation in land-use planning (seewww.oas.org/cdmp/document/kma/planning.htm).

I M PAC T

The work of the UWI Unit for DisasterStudies has been recognized both locallyand internationally. In 2003, the Unit wasawarded a Certificate of Distinction ofthe United Nations Sasakawa Award forDisaster Reduction. In addition, theInternational Landslide Research GroupAward for leadership in landslide hazardreduction in the Caribbean was conferredon 17 July 2003. The Unit was alsoawarded a “Best Publication Award” with-in the Faculty of Pure and AppliedSciences during UWI Mona ResearchDay, 18 October 2001. The award wasfor a paper on “Urban steeplands in thetropics: An environment of acceleratederosion”, published in collaboration withAvijit Gupta, University of Leeds, UnitedKingdom.

Natural hazard information is nowincreasingly being used in major civilengineering projects across Jamaica. Theenvironmental impact assessment (EIA)process in Jamaica is overseen by theNational Environment and PlanningAgency (NEPA). EIA reports availablefrom NEPA draw on the hazard dataresources identified earlier.

The website for the UWI Unit forDisaster Studies has proved to be a verypowerful tool in communicating informa-tion on natural hazards and natural


hazard maps. Funding is being sought toupdate the website and provide naturalhazard profiles and hazard maps for allCaribbean territories.

L E S SON S L EA RN ED

Although natural hazard maps are the-matic, they effectively communicateinformation on a variety of activeprocesses on the surface of the Earth. Forexample, landslide susceptibility mapsalso outline areas of accelerated soil ero-sion. Hence, the classification of hazardmaps in rigid categories limits theirpotential uses.

It appears that multiple hazard mapsat 1:5,000 and 1:10,000 scales are bettersuited for the general interpretation ofhazards and land-use planning.

LA N D S L I D E S

Knowledge of the causal and com-pounding factors that lead to landslidescan now be used to mitigate landslidehazards. Data collected and analysed byscientists at the UWI Unit for DisasterStudies – especially concerning theunderlying rock type and geologicalstructures such as the density of faults andjoints – are now being used to lay thefoundation for the establishment of earlywarning systems.

In many cases, damage from land-slides has been incorrectly ascribed todamage from floods. Research has helpedto highlight the significance and impact

of landslides. In order to reduce landslide-related losses, the planning andmitigation community must be educatedto change its perceptions.

Experience has shown that landslidesthat occur within 90 metres of roads areseveral orders of magnitude more severethan those that occur more than 90metres from roads. Landslide modelsdeveloped by UWI scientists are nowbeing used to help road engineers toimprove their road designs.

SE D I M E N T F L O O D S

Scientists at the UWI Unit for DisasterStudies have shown that disastrous floodevents occurring in Jamaica are often sed-iment-water flows rather than simplewater floods, as was commonly assumed.This distinction is important because mitigation strategies for sediment-waterflows are significantly different fromthose for water floods. Sediment-waterdisasters are amenable to avoidance andcorrection and economic losses may be significantly reduced with the appro-priate use of scientific data in designingmitigation strategies.

Landslide debris, which accumulatesat the base of slopes and in watercourses,is often mined to extract the aggregatematerial for the construction industry.This important economic resource hascreated business and employment oppor-tunities that sustain the livelihoods ofmany rural communities throughoutSIDS. A plan for debris managementshould be an essential component of thesediment-water flow mitigation.


FUTUR E P L AN S

Although information on historical natu-ral hazard events and disaster statisticsare readily available for the Caribbeanregion, it is rare to find dedicated, area-specific vulnerability and risk maps. Inaddition, the potential of existing hazardmaps in achieving natural hazard lossreduction has not yet been fully exploit-ed. Indeed, hazard mapping and hazardmaps are considered as the first steps inthe complex communication chain thatlinks land-use planning, sustainabledevelopment and loss reduction fromnatural disasters. Unfortunately, societalacceptance and the effective use of haz-ard maps prepared for Jamaica in the1990s still lie in the future. In the mean-time, a mechanism must be established tocapture user-generated feedback on exist-ing hazard maps. The challenges for theenvironmental professionals in Jamaicaare to utilize the extensive resource ofavailable direct and indirect hazard maps,provide feedback to mapmakers that willfacilitate the improvement of their mod-els, and suggest to decision-makers anddevelopers whether or not hazard mapsoffer anything new that might make disaster mitigation efforts more effective.In other words, information on hazardmaps has not yet been translated intoeconomic costs that would allow for cost-benefit analyses to be undertaken as aprerequisite for promoting sustainabledevelopment.

Having recognized this gap, scien-tists at the UWI Unit for Disaster Studiesaim to actively pursue vulnerability and

risk mapping as pilot projects in selectedareas and to develop methodologies relevant to the Caribbean region.

To this end, the UWI Unit forDisaster Studies has expanded itsresearch programme to include sedimentflooding, the impact of landslides on landdegradation in the Caribbean, andcoastal flooding processes, includingtsunamis and storm surges.

The landslide expert system that wasdeveloped in 2002 and 2003 in collabora-tion with the UWI Department ofComputer Sciences is being revised to adaptit for use in all of the Caribbean countries.

The website for the UWI Unit forDisaster Studies has proved to be a verypowerful tool in communicating informa-tion on natural hazards and natural hazard maps. Funding is being sought toupdate the website and provide naturalhazard profiles and hazard maps for allCaribbean territories.

MonaGIS, formerly Informatix Ltd.,the GIS hub for UWI, located on theMona campus, has collaborated with theUWI Unit for Disaster Studies to developa virtual landslide hazard guide for theKingston area. The guide has already beenprepared as a pilot project and will be repli-cated for other areas of the Caribbean.

In collaboration with MonaGIS,work is in progress to develop an interac-tive system for geocoding and indexingnatural hazards. Such a system will notonly provide a site-specific hazard profilebut also help to identify hot spots need-ing urgent intervention.


Although landslides are frequentevents in nearly all Caribbean countries,there is no institution within theCaribbean region dedicated to landslidehazard mitigation. The UWI Unit forDisaster Studies and the NorwegianGeotechnical Institute, therefore, haveagreed to collaborate to establish a centreof excellence in landslide and tsunamihazard management in the Caribbean. Aproject proposal is being finalized forsubmission to the Ministry of ForeignAffairs of the Government of Norway forfinancial support.

There are also plans to offer a four-week course on the analysis and manage-ment of natural hazards and risks at theUWI campus at Cave Hill, Barbados, forthe benefit of natural disaster manage-ment professionals in the easternCaribbean. The Caribbean DevelopmentBank has been approached to sponsorthis programme.

P U B L I C AT I O N S

Ahmad, R. (1995). Landslides inJamaica: Extent, significance, and geological zonation. In: Barker, D. and McGregor, D.F.M. (eds.), Environmentand Development in Small Island States: The Caribbean, University of the West Indies Press, pp. 147-169.

_____. (1996). The Jamaican earthquakeof January 13, 1993: Geology and geo-technical aspects. Journal of GeologicalSociety of Jamaica, 30:15-31.

_____. (2004). Natural hazard maps in Jamaica: Foundations for sustainable

development. Proceedings of the NationalScientific Conference on the Environment,Jamaica Institute of EnvironmentalProfessionals, Kingston, Jamaica, pp. 6.1-6.25.

Ahmad, R. and McCalpin, J.P. (1999).Landslide Susceptibility Maps for the Kingston Metropolitan Area, Jamaica, with Notes on Their Use. Publication No. 5, Unit for Disaster Studies, Dept.of Geography and Geology, Universityof the West Indies, Kingston, Jamaica,26 pp. + maps.

Ahmad, R., Clark, J., Manning, P.A. andMcDonald, M. (1997). The potential of bio-engineering in slope stabilization: Acase study from Jamaica. In: Ahmad, R.(ed.), Natural Management in the GreaterCaribbean and Latin America, PublicationNo. 3, Unit for Disaster Studies, UWI,Mona, Kingston, Jamaica, pp. 112-123.

Ahmad, R., DeGraff, J. and McCalpin,J.P. (1999). Landslide Loss Reduction: A Guidefor the Kingston Metropolitan Area, Jamaica.Publication No. 6, Unit for DisasterStudies, Dept. of Geography andGeology, University of the West Indies,Kingston, Jamaica, 36 pp. + maps.

Ahmad, R., Earle, A.H., Hughes, P.,Maharaj, R. and Robinson, E. (1993).Landslide damage to the Boar Riverwater supply pipeline, Bromley Hill,Jamaica: Case study of a landslidecaused by Hurricane Gilbert. Bulletin ofthe International Association of EngineeringGeology, no. 47, pp. 59-70.

Ahmad, R., Scatena, F.N. and Gupta, A. (1993). Morphology and sedimenta-tion in Caribbean montane streams:Examples from Jamaica and Puerto Rico.Journal of Sedimentary Geology, 85:157-169.


Carby, B.E. and Ahmad, R. (1995).Vulnerability of road and water systemsto hydro-geological hazards in Jamaica.Built Environment, 21:145-153.

Gupta, A. and Ahmad, R. (1999). Urban steeplands in the tropics: Anenvironment of accelerated erosion.GeoJournal, 49:143-150.

_____. (1999). Geomorphology and theurban tropics: Building an interfacebetween research and usage.Geomorphology, 31:133-149.

Northmore, K.J., Ahmad, R., O’Connor,E., Greenbaum, D., McDonald, A.J.W.,Jordan, C.J., Merchant, A.P. and Marsh,S.H. (2000). Landslide hazard mapping:Jamaica case study. NationalEnvironment Research Council, British Geological Survey Technical ReportWC/00/10, United Kingdom Departmentfor International Development (DFID)project no. R6839. 41 pp. + figures,maps and tables.

Case Study Prepared by:

Rafi AhmadAddress: Unit for Disaster Studies,Department of Geography and Geology,University of the West Indies, Mona, Kingston 7, JamaicaTel.: (+876) 927 2129, 2728Fax: (+876) 977 6029E-mail: [email protected]

Project Participants:

Rafi Ahmad: Project leader; head of Unit for Disaster Studies.

Phillipa Bennet: Development of landslide expert system.

Earl Brabb: Participation in the delivery of natural hazards summer course andmapping of landslide and other hazards;landslides.

Barbara Carby: Natural hazard mapping.

Jerry DeGraff: Landslides and geologicalenvironmental impact assessments.

Avijit Gupta: Joint research onCaribbean streams, flooding hazards,erosion and geomorphology in urbantropics.

Parris Lyew-Ayee: Innovative GISapproaches to communicate natural hazard information.

Paul Manning: Landslide mapping.

James McCalpin: Landslide susceptibilitymapping in the Kingston area.

Kevin Northmore: Landslide susceptibil-ity mapping in central Jamaica.

Ben Oostdam: Website development.

Edward Robinson: Natural hazard mapping.

Andrew Saunders: Website development.

Doug VanDine: Assisted in teaching thefirst workshop on debris flows and sediment flooding in the Caribbean; sediment floods.

Jan Vermeiren: Preparation of natural hazard maps and evaluation of landslide hazards.

living with natural hazards: jamaica - united nations development

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