I want to create high resolution and high accuracy "area of inundation" map using FLO-2D Model. I have high resolution Digital Elevation Model (DEM) and I must show small topographic details on my maps. To avoid the loss of these details, I need to use small grid size nearly 30 centimeters. If I select small grid size, grid number increases. So, my insufficient computer doesn't solve numerical schema of flood/rainfall modelling.
Do I divide study area some segments?
Or what can I solve this problem?