Preparing for Flood Hazard
Management:
The CADM experience
CADM Regional Team
Disasters
Many disasters, such as
earthquake, Tsunami
and hurricane, taking
place all over the world!
Floods : Hazards to tackle
with priority in the Caribbean
Floods are the most common,
frequent and serious hazards among
all disasters in the Caribbean.
Flood hazard management
Re-location
of people
Drainage
works
Early
warning
system
Approach for Flood Hazard
Management in the Caribbean
Comprehensive Disaster Management
(CDM)
Flood Hazard
Mapping
Community Disaster
Management
The first step for
all measures
Essential for any
measures to be
effective
CADM
Flood Hazard Map
Shows possible inundation areas, evacuation
routes, location of shelters, etc.
Used by:
• residents in risk areas for evacuation,
• disaster management agencies for
emergency operation,
• government agencies for mitigation works
and city planning,
• private sectors for investment plan.
Needed in homes and schools for awareness
of flood risk.
Community Disaster Management
Plan
Community Disaster Management Plan
(CDMP) is a plan describing early
warning system, evacuation system and
what community people should do before,
during and after flood event.
It should be in accordance with the national
and district plan.
CDMP is needed for timely action without
panic in the face of flooding.
On Producing Floodplain Maps in the Caribbean
1.
2.
3.
4.
5.
Expertise
Training opportunities
Data availability
Data acquisition
Tools for Map Production
Flood Hazard Mapping
G
RAINFALL
DATA
I
PHYSICAL DATA
OF CATCHMENT
S
RIVER
GEOMETRY
FLOODPLAIN
GEOMETRY
HYDROLOGIC
ANALYSIS
HYDRAULIC
ANALYSIS
FLOOD
HYDROGRAPH
WATER LEVELS
IN
FLOODED AREAS
G
I
S
FLOOD HAZARD
MAP
PRODUCTION ISSUES
Expert Needs
1. Hydrologic and Hydraulic expertise
– Normally performed by Civil Engineers as they are
trained in both areas
– Other scientists with graduate training in Hydrology
and sometimes Hydraulics
•
•
Sufficiently trained persons in the Caribbean to
perform tasks
FACULTY OF ENGINEERING, UWI has an
evolving programme focused on addressing the
needs of the CARIBBEAN
Expert Needs
2. GIS and Mapping Experts
•
There is a growing number of GIS technicians in
the region but the lack of GIS experts who
understands map projection issues and knows
how to formulate and resolve spatial modeling
problems are still under developed.
3. Hydrologists and hydrologic assistants for
network design, monitoring and operation
• Concentrated numbers in some countries,
e.g., Trinidad and Jamaica. Others exist in
other countries, but perhaps not in sufficient
numbers.
Training Opportunities
NEEDED
EXPERTS
Hydrology and
Hydraulic
Analysts
MAPPING
EXPERTS
HYDROLOGICAL
ASSISTANTS
REGIONAL TRAINING
INSTITUTE
U. W. I.
FACULTY OF
ENGINEERING
ST. AUGUSTINE
C. I. M. H
READINESS TO
TRAIN
CIVIL ENGINEERING
PROGRAMME
SURVEYING AND
LAND INFORMATION
PROGRAMME
PROGRAMMES
FOR WATER
RESOURCES
TECHNICIANS
Data Availability
Physical Data
– Generally available
– Land cover and soils data extracted from old
paper maps
Ikonos satellite imagery available (or can be
obtained) for most countries to update
land cover information
Topographic data for hydrologic studies
available from contour maps.
DEM has been built from them
Elevations on floodplains not widely available
Data Availability
Hydrologic Data
–
Major deficiencies that can limit the accuracy of the maps
1. Streamflow
– Very few countries have long term streamflow records
» Usually problematic because of difficulty in gauging
steep streams that are common in the Caribbean
» Other problems of short staff to perform the gauging
– Missing streamflow records prevent ability to validate
models
2. Rainfall
– Very few countries have rainfall data to determine the
rainfall versus depth relations at various places on the
islands.
– Relation is important for estimation of runoff
– Generally large amounts of daily rainfall data throughout
the Caribbean
Data Availability
G
RAINFALL
DATA
I
PHYSICAL DATA
OF CATCHMENT
Physical data generally available in
digital format. Issues about:
•currency of land cover information
•Resolution of DEM
S
RIVER
GEOMETRY
FLOODPLAIN
GEOMETRY
HYDROLOGIC
ANALYSIS
HYDRAULIC
ANALYSIS
FLOOD
HYDROGRAPH
WATER LEVELS
IN
FLOODED AREAS
G
I
S
•Rainfall data lacking temporal distribution
•Flood hydrographs not available for calibration
of models
•Limited flood levels available for modelling
Data Acquisition
Generally inadequate administrative units exist
throughout the Caribbean for hydrologic
database development and management and
application of data for water resources
management, including flood hazard map
production.
As a result, many countries not immediately ready
for improving their hydrologic database, even
with acquisition of instruments for database
development
Problems stem from:
– Inadequate staffing
– Inappropriate staffing
– Lack of instrumentation (Catch 22)
Tools Needed for Map Production
•
Well-established Administrative Unit (Water Resources
Agency or Drainage Unit) that has a clear mandate for map
production
•
Well-staffed unit, including:
–
–
–
Civil engineers
Hydrologists
Technical support staff, including
• Draughtsmen, engineering assistants, hydrological assistants
•
Well-equipped Unit, including:
•
Hardware (minimum requirements)
–
–
–
–
–
–
–
Computers—no extraordinary specifications are required
Large format plotter
Heavy duty printer
Surveying equipment
Rainfall gauges, including recording gauges
Appropriate current metering equipment
Stage recorders
Tools for Map Production
Software (minimum requirements)
– WMS or appropriate software for hydrologic
analysis
– HEC-RAS and FLO-2D, or appropriate
software for 1-D and 2-D hydraulic analysis
– GIS software
– Microsoft suite
DATA AVAILABILITY IN THE THREE PILOT CATCHMENTS
Mesopotamia
Speightstown
San Juan
Physical Data
•Land cover
•Soils
•topography
•Old land cover maps
•Soils map available
•Contour maps
•Old land cover maps
•Soils map available
•Contour maps
•Old land cover maps
•Soils map available
•Contour maps
Rainfall Data
•Time
•Space
•amount
•Time—Montreal gauge •Time—Sedge Pond
•Space—Limited
•Space—Limited
•Amount—Dumbarton •Amount—Bdos drain
study
Observed
streamflow
unavailable
River Geometry Available;
To be checked
unavailable
•Gauge within area
•More than one in area
•Long term stations
•Long term station
on the river
but quality needs
verifying
Available; adequate
Available; adequate
Available at 25 m grid
intervals
Floodplain
Geometry
Available at 30 m grid
intervals
Available at 25 m grid
intervals
Past flood
levels
One on record01 Oct, 1999
One on record31 Oct 1984
•May have several
events
Principle:
by/for community people
Discussion on
activities in flood
events
Planning by
using the map of
their community
area
Community Disaster
Management Planning
• Establishment of Plan Development
Committee (PDC)
• Definition of Community
• Preparedness/Mitigation Planning
• Emergency Response Planning
• Recovery/Rehabilitation Planning
Institutional Cooperation
1.
2.
3.
4.
5.
6.
7.
8.
9.
10.
11.
12.
13.
14.
15.
Ministry of Community/Social Development
Town and Country Planning Authority
Drainage Division
Ministry of Agriculture
Water Resources Agency
Ministry of Housing
Lands and Surveys Department
Meteorology Department
NEMO
Local Government Authority
Utilities: Water Supply and Electricity Supply
Resident Associations
Insurance Industry
Mortgage Finance Industry
Industry and Chambers Associations.
Location of Pilot Areas/Countries
CADM
Pilot States /
Communities
St. Vincent & The Grenadines
Mesopotamia
Trinidad & Tobago
San Juan
Barbados
Speightstown
Next steps
Extension of CADM
Caribbean
Community Regional
Programme
Framework 20052015
Sustainability
plan
Communities
FHM
FHM
FHM
CDMP
CDMP
CDMP
Next Steps
• Capacity building in the training
institutions;
- UTEC,CIMH, UWI
• Build capacity to produce maps for
different types of flooding; riverine,
depression/sinkhole, groundwater
induced
Challenges
• Convince governments and
decision makers to train
professional and keep trained
professionals
• When we lose them, train
more
• Need for standardized terms
to eliminate confusion
CADM Regional Team
• CDERA
Jeremy Collymore
Andria Grosvenor
Donovan Gentles
Elizabeth Riley
Anderson Harris
Pamela Knights
UWI
Balfour Spence
Jacob Opadeyi
CIMH
Kailas Narayan
WRA, Jamaica
WRA, Trinidad & Tobago