Floods Disaster Medical Support and management
Written by Anam Hussain
Definition
A flood is defined as an expanse of water that submerges land. The EU Floods directive defines a flood as a covering, by water, a land which is not normally covered with water. The first medical activity performed is medical intelligence.
Floods are classified based on different criteria.
- By origin
- By range
- By intensity and repeatability
- By origin classified as
- Natural: precipitation, riverine, snow melting, river barrages, tsunamis, coastal or estuary tidal overflow
- Man-made: dam or other hydro-ameliorative failures, dam water release, deliberate river flows barrage
- By range classified as
- Local: flooded area is surrounding particular river or stream or hydro ameliorative channels
- Mid-range: flooded regions includes several rivers
- Large range: when extended territories are flooded including several administrative territories
- Great range: floods extend on great majority or entire country or even affects trans-boundary territories
- By intensity and repeatability classified as
- Slight: occur every 10-20 years causing minor-moderate damages
- Dangerous: recorded every 20-40 years. Large territories are submerged with water causing threat to animal and human life
- Very dangerous: recorded every 40-80 years with significant impact on infrastructure, environment and population
- Devastating: observed every 80-150 years, depth above 2m, speed above 10km/h. results in great material losses, irreversible and medical losses
- Catastrophic: above 100 years, great speed, tidal wave, depth. Enormous material damages and great number of casualties.
Main damaging factor of the flood is overpressure due to its affect on the amount of water and its speed. Always in a case of flooding, secondary factors are also present:
- Thermal: cooling, freezing of water body
- Biological: depending on infrastructure damages and time water remains in area
- Psychological: victims always present with some sort of shock and panic
Flood features are used to analyse the flood impacts. These features include:
- TF: time for first wave arrival
- TC- time for water disappearance
- V-speed of flood wave
- H-depth of flood wave
- L-length of affected territory
Depending on the expression of the aforementioned features, 4 zones in the flood AOD can be defines:
- Zone 1: Tidal wave
- Is most dangerous for population because it is closest to the origin of the flood, length of affected territory is up to 10km, speed of flood wave is above 30km/h, time for first wave arrival is minutes, time for water disappearance is less than 30 minutes
- Casualties are often drowned, have severe traumas, thermal injuries and 100% are psychologically affected