FEMA
HAZUS-MH

Johnson County Emergency Management and Homeland Security Collaborates with the
University of Iowa Department of Geography to Assess Flooding Impacts Using HAZUS-MH


HAZUS User Groups Success Story

FEMA Region VII

Johnson County Emergency
Management and Homeland
Security Collaborates
with the University of Iowa
Department of Geography
to Assess Flooding Impacts
Using HAZUS-MH


Background

On June 9, 2008, forecasts for the Iowa River through Johnson County,
Iowa, were expected to approach or exceed the record levels set in 1993.
Aware of the benefits of HAZUS-MH for estimating the potential losses
from flood disasters, Johnson County Emergency Management Director
Dave Wilson consulted Shane Hubbard from the University of Iowa to
utilize HAZUS to assess the potential impacts of the approaching flood
event. These analyses were coordinated within the Johnson County
Emergency Operations Center and shared with each of the Emergency
Support Functions (ESFs). With the crest of the river not expected to
occur for seven days, the results of the HAZUS-MH analyses were used
to assist in planning initiatives throughout the county.


Details

Johnson County GIS staff supplied data which was formatted to create a countywide dataset of building locations with
necessary attributes to update the HAZUS-MH building inventory. Initially there were no official forecasts for the water
levels along the Iowa River in Johnson County. A preliminary HAZUS-MH analysis began by simulating the 1993 flood event
from historical discharges recorded along streams within the county. As the National Weather Service (NWS) and U.S. Army
Corps of Engineers (USACE) began to forecast the approximate discharge values for the Iowa River through Johnson County,
the model was initialized to reflect those forecasts. Toward the week's end a consensus was reached on a flood forecast.

A final HAZUS-MH analysis was generated creating a flood boundary and loss estimate. The updated building information
along with the expert-supplied discharge data represented a Level II analysis.
In the days leading up to the final crest, numerous roads were closed due to high water. Road closures inhibited the ability
for Emergency Medical Services (EMS) to serve the county during the disaster. EMS turned to HAZUS-MH for answers.

HAZUS-MH flood boundaries were intersected with local GIS road networks and elevation data to create an estimate of
upcoming road closures. Creating this analysis days before the event gave EMS staff time to prepare for alternative routes
to navigate around the county.
Johnson County Emergency Management and Homeland Security Collaborates with the
University of Iowa Department of Geography to Assess Flooding Impacts Using HAZUS-MH


HAZUS-MH was used to highlight critical facilities which might be affected
by flooding and this information was used to navigate sandbagging efforts.
It was determined the Johnson County Administration Building, home to the
County Board of Supervisors, the Auditor's Office, GIS staff, and other offices
crucial to the functionality of county services could be affected. Based upon
historical flooding and the HAZUS-MH analysis, the building was protected
with sandbags. Mid American Energy was concerned with the inundation of
an electric substation that supplied power to Iowa City, which contains 56
percent of the population of the county. HAZUS-MH was used as one tool to
assist in the protection of the power substation.


HAZUS-MH Statistics

A final HAZUS-MH analysis created on the day of the flood crest calculated 265 buildings would be moderately damaged and estimated
1,100 households would be displaced from the flood. Preliminary damage assessments from the Iowa Department of Homeland Security
Division of Emergency Management estimated 303 buildings sustained at least moderate damage. An analysis of the structures
evacuated within Johnson County by the Johnson County GIS staff resulted in nearly 1,300 households evacuated. Once again, HAZUSMH
proves to be highly accurate.


Collaborations

HAZUS outputs-such as the maps on this page-facilitated the
collaboration of federal, state and nonprofit organizations during this
disaster. HAZUS-MH results quantified the numbers of displaced households
which allowed for the American Red Cross and the Salvation Army to plan
their response efforts in terms of resources required based on need. HAZUS
maps showing the location of the flooding event expedited the process of
getting help to people in need.

The Emergency Management Division of Iowa Homeland Security used
HAZUS-MH maps and data to understand the severity of flood damage
likely to affect the area. The HAZUS data and maps provided situational
awareness above and beyond what was available for the county during the
statewide response.

FEMA Community Relations Cadre Staff contacts residents in person in areas which have sustained damage during a disaster to be sure
they are aware of FEMA and other agency disaster assistance. Being able to accurately predict which structures were affected greatly
increases their efficiency, as well as their confidence in knowing they can locate disaster victims in a systematic way. The HAZUS-MH
maps and data provided to the FEMA Community Relations staff were extremely useful and, so far in their experience, have accurately
predicted which structures were damaged by the
flood event. The HAZUS-MH data allowed the staff
to prioritize their efforts in Johnson County and
reach as many people as possible.


Program Contacts

Shane Hubbard
Department of Geography
The University of Iowa
P: 608.215.6059
E: shane-hubbard@uiowa.edu


Sue Evers
HAZUS Program Manager
FEMA Region VII
P: 816.283.7005
E: sue.evers@dhs.gov