Zhihao Wang and Chris S. Renschler,
University at Buffalo - State University of New York, Landscape-based Environmental System Analysis and Modeling Laboratory:
In August 2011, Hurricane Irene swept through a large area in New York State, leaving millions of people homeless and cities in pieces. The damage there was widespread and astonishing, whereas the precise scale of the floods is still unclear. The crucial part of modeling a flood is to decide its return period, especially for the un-gauged areas. This research aims to model the flood inundation and decide the return period using HEC-RAS model, assisted by ArcGIS, incorporating multiple sources of data.
This research focuses on an area located in the Schoharie Watershed between North Blenheim and Breakabeen, which was attacked by Irene-invited floods and has U. S. Geological Survey (USGS) gauging stations on both ends. HEC-RAS utilizes 10m USGS DEM, LiDAR data, NLCD land-use data, and flow rate data from two nearby gauging stations as input parameters. In addition, aerial imagery taken two days after the peak flooding using an RIT/IPLER airborne multi-sensor platform was inspected visually to establish the flood extent. Model results were validated against field observations, and previous FEMA flood model results. The modeling process, once validated, can be applied as important reference instruction to guide the best management plans for the decision makers and stakeholders.