1. Hazard Assessment with GIS
Initial Explorations of
Hazus MH and Local Data
For TJPDC
By David L. Phillips
With
Nicole Gilkeson
Leigh Rosen
Lory Pendergraph

2. Planning with Disaster in Mind
An applied GIS course
Cooperatively with staff of Thomas Jefferson Planning District Commission—A multi-county ecologically diverse region
2.5 months effort

3. Aims
Help Identify and Map Region’s exposure to natural hazards as indicated by National sources.
Construct website to document and raise public awareness of hazards in region
Assess Inventory of Critical Facilities as provided by HAZUS
Assess the usability of HAZUS-MH for a multi-county region
Assess the availability of local data

4. Aims
Help Identify and Map Region’s exposure to natural hazards as indicated by National sources.
Construct website to document and raise public awareness of hazards in region
Assess Inventory of Critical Facilities as provided by HAZUS
Assess the usability of HAZUS-MH for a multi-county region
Assess the availability of local data

5. Probability of a Hurricane
Hurricanes
Probability of a Hurricane
The TJPDC area has a less than 2 percent probability of experiencing a hurricane during hurricane season.

6. Earthquakes
1996 Data

7. Wildfire
According to the Virginia Department of Forestry a large portion of the TJPDC has a high risk of wildfire, shown here in red.

8. Dam Failure
The TJPDC has a total of 12 dams, 6 of which are considered a high hazard risk.

9. Floods
100-year floodplains indicate 1% chance of flooding each year.

10. Floods

11. Hazus-MH Multi-hazard Impact Simulation Models Hurricane Flood
Earthquake
Each model estimates impacts for region
Our experimentation allowed some rough assessments

12. Modeling Impacts Modeling Natural Hazard Direct Physical Damage
Induced Damage
Direct Economic Losses
Indirect Economic losses

13. HAZUS_MH Hazard Impact Assessment:
Levels of Refinement and Sophistication
Modifies cost and damage parameters to local conditions
Uses locally acquired data about buildings, population, terrain and natural features.
Uses widely available but generalized data

15. HAZUS-MH Critical Facilities
An very good set of the types of facilities considered important from a national perspective:
Hospitals, fire stations, police stations, schools, churches, transportation facilities, etc.
Systematic consistency across the jurisdictions

16. HAZUS-MH Critical Facilities
Listings found to be incomplete and sometimes inaccurate:
Recent facilities missing (Schools, hospitals)
Wrong addresses or reported to be located at “headquarters” address.
Occasional Incorrect Location

17. HAZUS-MH Building Inventory
Undercounts the number of business locations for some sectors
Agricultural
Religious

18. HAZUS-MH Hazus – MH building inventory:
Estimates 72,870 buildings in TJPDC
72,000 residential
715 commercial
32 governmental/educational
74 industrial
33 religious
County building planimetrics give 149,870 buildings. Many of these are out-buildings.

19. Using HAZUS Impact Model
Multiple scenarios gave local planners “a feel” for the magnitudes of impacts for different intensities and different hazards

20. Using HAZUS Impact Model
TJPDC is “on the fringe” of HAZUS-MH model validity
Earthquake damage over estimated at lower (5.0 and below) intensities.
Hurricane model “stops” when storm degrades to tropical storm.

21. Using HAZUS Impact Model
TJPDC is “on the fringe” of HAZUS-MH model validity (continued)
Flood model designed for detailed study of small or modest “reaches” not regional watersheds.
Flood model focuses more on inundation and less on velocity impacts.

22. Using Local Data
Local planimetric data on building footprints allowed:
Focused location of buildings rather than Hazus Census Tract or Census Block level aggregates.
Local floodplain maps used in conjunction with building footprints identified “Critical Reaches”

25. Direct GIS measurement of flood exposure

27. Testing Historic Events
Hazus contains some historic events
Hurricanes: 1949, Fran, Hazel
These are run against current inventory of population, buildings and critical facilities—likely to over estimate historic event impacts.
We were able to get a digital data set of building stock for two jurisdictions. This will allow some “scaling” of model impacts to test the model against historic reporting of damage.

28. Using even rough results
Local planning taskforce beginning to:
Assess the likelihoods of different hazards
Assess the magnitudes of the impacts of different hazards

29. Discussion of the Assignment of Likelihoods

30. Discussion of the Assessment of Severity of Impacts

31. Using Local Data To Validate HAZUS Data
Map HAZUS Critical Facility Data
On Local Detailed Maps
Use local experts to identify errors or omissions

33. Charlottesville Floodplain Insert

34. Charlottesville Floodplain Insert With Identified Data Problems
Fire station Miss-located
Charlottesville Floodplain Insert
With Identified Data Problems
County Police Station Missing
Flood Plain may need study
New Hospital Missing
Montecello not listed as Significant Cultural Facility
Montecello High School Missing

35. Hazard Assessment with GIS