Flood in Thailand is the largest flood disaster in the last 100 years. Area affected by flooding in Thailand at present is more than twice of Java island (Java = 126,700 sq km) or less extensive than half of Sumatra island. Water levels ranging from 30 cm to 400 cm, and some areas even more than 4 m.
Until October 23, 2011, using data from RADARSAT-1, extensive inundation has reached 289,337 sq km, almost 62% of Sumatra island (Sumatra = 470,000 sq km) and caused more than 300 people died and millions of people who still live scattered throughout the affected areas.
I tried to find out the water situation under normal conditions using Landsat satellite imagery (aquisition date: January 1, 2011, which I have edited using additional data with acquisition January 14, 2010 and January 11, 2009 to close the gap), I found that most areas flooding is a flat area with mostly land use is agricultural crops.
Look at the picture below, the blue color is water under normal conditions, water was in agricultural areas, rivers, and lakes. At the time of flood, water has submerged the entire area of agriculture and many farm villages have been suffered (red circle).
Note: I only use one scene of Landsat satellite imagery data for Thailand region. The above picture does not show the whole affected area. For more details you can refer to this page (http://flood.gistda.or.th/), but in Thailand language.
This flood will surely cause the farmer suffered, which their main income is come from agricultural crops.