Risk Map Early Demonstration Project

1. Risk Map Early Demonstration Project Lackawanna County, PA CCO Meeting September 13, 2011

2. Outline • Overview of Risk MAP • Early Demonstration Project Scope • Summary and Results • Questions

3. Risk MAP Vison Through collaboration with State, Local, and Tribal entities, Risk MAP will deliver quality data that increases public awareness and leads to action that reduces risk to life and property.

4. Early Demo Project Scope • Develop Risk MAP Products • Changes Since Last FIRM • Multi Frequency Raster Flood Datasets • 3D Flood Elevation • Flood Depth • Risk Communication Datasets • % Annual Chance Layer • Probability of Flooding in 30 years Layer • Areas for Potential Mitigation

5. Early Demo Project Scope • Develop Risk MAP Products • Risk Assessment Analysis • Using FEMA’s HAZUS Software • Flood Risk Database • Flood Risk Report • Flood Risk Map

6. Changes Since Last FIRM-CSLF- • What is it? • GIS layer depicting the changes in SFHA and Floodway since previous mapped FIRM • Quantifies Land Area • Zone Changes • Contributing Engineering Factors (Why?) • Uses: • Communication and Outreach • Public Notification through Mailings • Internet Outreach Applications

7. Changes Since Last FIRM-CSLF- Early Demo Results • SFHA Changes • Total Area: 18 sq. miles • Increase: 6.35 sq. miles • Decrease: -9.85 sq. miles • Net Change: -3.52 sq. miles • Floodway Changes • Total Area: 2.57 sq. miles • Increase: 2.35 sq. miles • Decrease: 0.0 sq. miles • Net Change: 2.35 sq. miles

8. Water Surface GridsMultiple Return Periods • What is it? • GIS datasets showing 3D flood elevations every 20 feet throughout the floodplain. • Developed using results from computer modeling and is basis for flood depth grids. • Developed for multiple flooding events (10%, 2%, 1%, 0.2%) countywide, where applicable. • AE and A Zones • Uses: • Hazard Communication and Outreach • Efficient BFE Determination • Could be paired with building specific data (FFE, values, etc.) for loss estimations

9. Depth GridsMultiple Return Periods • What is it? • GIS datasets showing flood depths every 20 feet throughout the floodplain. • Developed by subtracting 3D flood layer from ground surface. • Developed for multiple flooding events (10%, 2%, 1%, 0.2%) countywide, where applicable. • AE and A Zones • Uses: • Hazard Communication and Outreach • Loss Estimation Using FEMA’s HAZUS software.

10. Velocity GridsMultiple Return Periods • What is it? • GIS datasets showing average flow velocities throughout the floodplain. • Developed for new detail study only. • Developed for multiple flooding events (10%, 2%, 1%, 0.2%) countywide, where applicable. • Uses: • Hazard Communication and Outreach • Risk Assessment. • Combined with Depth Information for damage potential.

11. Percent Annual Chance Grid • What is it? • GIS layer showing the “threshold” flood that inundates a given land area (ex. 75-year flood) • Also known as the “Percent Annual Chance Grid” • Uses: • Hazard Probability Communication • Efficient / real-time flood mapping of non-standard flood events. • Used as basis of developing the percent 30-year grid.

12. Percent Chance of Flooding in 30 Years Grid • What Is it? • Estimates the probability of flooding at least once during a 30 year period • Developed using the percent annual chance grids • Uses: • Probability Communication • Goes beyond the traditional “in or out”phylosophy

13. HAZUS Loss Estimations • Flood Losses (per census block) Computed using Census Data and multi-return depth grids • Separate scenarios created for each return period

14. Areas of Mitigation Interest-AOMI- • Dataset which identify areas where mitigation efforts could be potentially effective • Locations were determined from the effective FIS as well as the local Hazard Mitigation Plan

15. Flood Risk Database

16. Flood Risk Report

17. Flood Risk Map

18. Questions Thank You