The Iowa Department of Homeland Security and Emergency Management (HSEM) seeks to determine the areas of the state that have the greatest Potential Of using a Watershed Approach to Reduce Floods. One method of determining this is by finding the HUC 12 watersheds that have the most building area inundated on an average annual basis as compared to the total area of the upstream watershed area. Retrieve GIS Data: 4.1.1. Retrieve necessary 2D BLE GIS data from the Iowa Department of Natural Resources (DNR) Floodplain Mapping Data Platform (https://idnr.engage.stantec.com/#/mapcomponent) that contains: 4.1.1.1. The area inundated by the 5-year recurrence interval (20% chance flood, or 5- year RI); and 4.1.1.2. The area inundated by the 10-year recurrence interval (20% chance flood, or 10- year RI); and 4.1.1.3. The area inundated by the 25-year recurrence interval (4% chance flood, or 25- year RI); and 4.1.1.4. The area inundated by the 50-year recurrence interval (2% chance flood, or 50- year RI); and 4.1.1.5. The area inundated by the 100-year recurrence interval (1% chance flood, or 100-year RI); and 4.1.2. Retrieve the latest publicly-available Microsoft Bing building footprints in the State of Iowa. 4.2. Description of Work for Each HUC 12: 4.2.1. With the retrieved GIS data, use GIS and other tools to calculate: 4.2.1.1. the total building square feet in each HUC 12 inundated by the 20% chance flood; 4.2.1.2. the total building square feet in each HUC 12 inundated by the 10% chance flood; 4.2.1.3. the total building square feet in each HUC 12 inundated by the 4% chance flood; 4.2.1.4. the total building square feet in each HUC 12 inundated by the 2% chance flood; 4.2.1.5. the total building square feet in each HUC 12 inundated by the 1% chance flood.
