1. Past flooding data Belgium
Wouter Vanneuville
CRED, Brussels

2. Outline Belgium? Flanders? Sources of data about past floods
Conclusions
Database

3. Belgium? or Flanders? Meteorology: B
Water level / flood predictions: regions
Water management: regions ( + provinces, cities and villages, …)
Crisis management (civil security): B (+ provinces, cities and villages
Decree on integrated water management: Flanders
Law on natural hazards (insurance): federal Belgium

4. Belgium? or Flanders? For this presentation:
Partim past floods: Belgium
Partim database: Flanders

5. Past floods

6. Past floods Weather events (1901-2000) Floodings due to rainfall
Floodings due to storm tide (to a limited extend)
Quantitative: mm rainfall
Qualitative: flood impact
“no information” for calibration of flood hazard and risk maps as defined in EU Floods Directive

7. Past floods
Zenne catchment (part of river Scheldt basin, incl. city of Brussels)
Very detailed in its description
Limited quantitative information

8. Past floods Socio-economic evaluation of the 1995 floods
Focus on tangible effects
Not only direct damage, insured damage, households and agriculture
Belgium

9. Past floods Evaluation of tools Flood delineation Flood damages
Results of models compared with data from the disaster fund
No perfect match!

10. Past floods municipality level versus (sub)catchment Public goods
Franchise influencing number of file records?

11. Conclusions – past floods
Preliminary exercise!
Heterogeneity of source data used
Focus on rainfall driven events
We got a file with 23 events
1 unknown
44 new
subjective selection based on descriptions
12 information added
Mostly qualitative information

12. Database
Belgium: CALIS (Service public fédéral Intérieur - Direction des Calamités)
Since 1993
Event and impact
65000 records

13. Database Flanders: Recently flooded areas (ROG)
ROG information since 1988 (first compiled in 2000)
Event information
GIS layer (vector)

14. Helicopter with WES cam makes movie during flood
Database
Collection of information:
Topographic maps given to municipalities to draw contours
Helicopter with WES cam makes movie during flood
Interpretation of images by Agency for Geographic Information Flanders (AGIV), since 2007

15. Database Collection of information:
“Correction” of information based on digital elevation model (DHM Flanders)
: Coordination Commission for Integrated Water Management (CIW) visits all- affected municipalities, information directly drawn on computer
Impact information is collected as well (water levels above doorstep, damages, …)

16. Floods in Flanders 10/2009: river IJzer
Return period Q IJzer (main river): > 100year
Flooded area > 30km² - Damage limited

17. Flood maps LOT Foto overstroming rond sluis Lot (14/11/2010 14u)
Overstromingskaart omgeving Lot (14/11/ u)

18. 30/11/2009 AGIV - WATLAB Samenwerking met AGIV-Robberechts
Rampenfonds – Afijken Modellen – Snel overzicht voor beheerders
AGIV - WATLAB 18

19. Conclusions Different databases at different levels
Detailed event information separated from detailed impact information
Different reactions on collaboration with insurance industry since ‘law on natural hazards’ came into force