Coastal Flooding Analysis Using LiDAR and DEM Data

For this lab, I worked with LiDAR and DEM data to study the impacts of Hurricane Sandy and storm surge flooding in New Jersey and Florida. In Part A, I downloaded and converted LiDAR data for Mantoloking, New Jersey, to create pre and post storm elevation models. I used the LAS Dataset to TIN tool and then converted the TIN to raster to visualize elevation changes. After that I used the raster calculator to subtract the pre storm surface from the post storm surface to see where erosion and deposition occurred.

Part B focused on analyzing building damage by looking at the change layer with building footprints. I reviewed bookmarks that showed different areas impacted by the storm. These bookmarks made it easier to compare areas with high erosion or sand deposition to where buildings were located.

In Part C, I compared LiDAR and USGS DEM based flood models for Cape May County, Florida. I used the provided DEM layers and storm surge polygons to see which buildings were affected. I selected buildings by location to figure out which ones were impacted by each elevation model. After that I counted the number of residential, commercial, garage, and shed buildings impacted in each model and calculated the error of omission and commission.

Overall, this lab helped me better understand how LiDAR and DEM data can be used to model storm surge flooding and building impacts. I learned how to create elevation models from LiDAR data, analyze elevation change after a storm, and evaluate the accuracy of different DEMs in predicting which buildings would be flooded.