The Importance of GIS in Emergency Management

By Monika Holser, UCLA School of Law, Class of 2018 

GIS (geographic information system) is a computer system for “capturing, storing, checking, and displaying data related to positions on the Earth’s surface.”[1]  It allows multiple layers of information to be displayed at once, enabling one to visualize and understand relationships on a map.[2]  Different types of information can be overlaid in the program regardless of their original format or source.[3]  According to ESRI, GIS is described as the “go-to technology” for location-based decisions and is fundamental in understanding the current and future issues involving geographic space.[4]

The modern growth of geospatial technology positively interacts with, and influences all aspects of disaster management – such as mitigation (modeling hazards and vulnerability to develop strategies), preparedness (formulating emergency response and evacuation plans), response (executing such plans), and recovery (assessing damages, rebuilding, preventing recurrence, and educating the public).[5]  Considering we cannot prevent natural disasters, it is important to determine potential hazards and where they stand in relation to our communities.  As a visualization tool, GIS can assist in locating, identifying, and understanding relationships between areas of social vulnerability and potential hazard exposure.  For example, available U.S. census data can be layered onto a map to include the distribution of age, income, ethnicity, housing quality, transportation capacity, etc.[6]  This information can be used to create appropriate mitigation strategies, to identify how or where certain areas should be evacuated, or even how first responders (law enforcement, medical personnel, fire service etc.) should approach certain areas during a disaster.[7]

Furthermore, with advances in GIS and computer technology today, individuals and communities can potentially use the increasingly accessible tools to manage their own knowledge and community data.[8]  If promoted within communities, GIS can be utilized to communicate risks and hazards to the population with no requisite specialized knowledge.[9]  Currently, many communities and homeowners lack the knowledge and motivation to take appropriate cautions or mitigate potential hazards.  Having access to personalized and compelling visuals may ameliorate the issue, while providing local governments invaluable information for disaster management and preparedness.[10]

Challenges and Future Steps – A Look at FEMA Flood Mapping

First and foremost, data is the most essential element of GIS mapping – the program itself merely creates a visual display of the inputted data.[11]  Without accurate data, the program cannot produce accurate depictions of the desired information or relationships between them.  Therefore, the greatest challenge is the weakness of current data, or the lack of data in general.  Although currently improving, there is also a deficiency of readily available GIS software, and more importantly, a failure in the communication/utilization of GIS and the information it can provide.[12]

Considering the significant role GIS already plays in emergency management, I believe the government, as well as local governments, should be allocating funds to improve each of these three issues.  First, to increase data collection and to improve the accuracy of existing data, second, to promote the use of GIS software by communities, and third, to improve the accessibility and communication of the information produced.  In regards to these aspects, I would like to discuss the ongoing Federal Emergency Management Agency (FEMA) flood mapping as part of the National Flood Insurance Program (NFIP).

The NFIP was created to provide a means for homeowners to financially protect themselves from flood events – flood insurance is offered to property owners if the community participates in the NFIP and meets floodplain management ordinances established by FEMA.[13]

FEMA’s flood hazard mapping program, Risk Mapping, Assessment and Planning (MAP), identifies flood hazards and assesses risks of certain areas.[14]  This mapping is used to create the Flood Insurance Rate Maps (FIRMs), the basis of NFIP regulations and insurance requirements.[15]  The FIRMs are then used to determine insurance premiums and set minimum floodplain standards for communities based on the assessed risks of the particular location.[16]   Currently, the NFIP states that it is working towards updating the accuracy of flood maps and providing policyholders with information to better understand the program.[17]

1. Improving Accuracy of GIS Data

In cost-benefit analysis, hazard mapping is found to have positive net benefits, thereby indicating that it is beneficial to work towards improving the accuracy of our mapping.[18] A study conducted by FEMA in 2000 found that when considering all costs (flood data updates, map maintenance, new mapping, conversion to new standards, and customer service), the flood maps created a benefit of 1.33 billion dollars, with a cost of 799 million.[19] Currently, flood maps are used an estimated 30 million times a year by government agencies, FEMA contractors, lenders, insurance agents, land developers, community planners, property owners, realtors, and by others for risk assessment, land management, mitigation, and disaster response.[20]  With this in mind, it is clear that the accuracy of these maps is vital and relevant to widespread decisions.

For example, improving the accuracy of FEMA’s flood maps is predicted to directly affect the insurance rates and land use.[21]  More accurate estimates of flood risk allow appropriate insurance premiums to be calculated for certain areas and particular structures.[22]  The accuracy of price may also increase the understanding and trust of flood risk, and therefore encourage and ensure insurance coverage.[23]  In connection to land use, the correctly priced insurance premiums accurately reflect risk, and in turn, reduce the development of land in high-risk areas.[24]  Improvements in accuracy can add restrictions to properties that should have been designated at-risk (reducing future losses of life and property), and conversely, lifting restrictions in areas that were incorrectly designated at-risk (lowering costs and mandatory improvements, enabling the land to be used in other ways).[25]  In fact, FEMA’s website includes an option to contest floodplain boundaries if homeowners believe their properties were incorrectly identified in high-risk areas – increasing accuracy of flood maps may therefore reduce the contesting of boundaries and save time, money, and effort of all parties.

Learning from the NFIP and FEMA’s FIRM flood maps, we can see that it is indeed beneficial to invest in data collection for GIS use in emergency management.  This can be applied to any context, rather than solely floods and national flood insurance – perhaps to fire or earthquake risks, or anything relevant to a community’s planning.

2&3. Promoting Use of GIS Software and Improving Communication of Risks

Little research has been done to show how to effectively communicate risk to the public through hazard maps.[26]  However, previous studies have shown that in particular, there are issues with communicating via FEMA’s FIRM flood maps.[27]  Taking it upon myself to investigate the FEMA website, I found it very difficult to navigate and understand.  There is an overwhelming amount of information and it is unclear how or who it is intended to be used by.  Through the Flood Map Service Center ‘Search by Address’ page, a homeowner can simply type in their address to pull up an interactive flood map, National Flood Hazard Layer (NFHL).  This is where the seemingly simple task becomes complicated.  I downloaded the map corresponding to my current apartment address only to find that I had absolutely no idea what I was looking at, or what any of the data meant.  I then managed to locate an FAQ page on the website, linking a 54 page document available for download titled, “How to Read a Flood Insurance Rate Map Tutorial.”  It is quite possible that I did not spend enough time attempting to read and understand the guidance provided by the FEMA webpage, but it is clear why a homeowner or individual with little to no experience in this area would fail to understand the implications of the data.

Furthermore, FEMA’s in-house mapping software, HAZUS, is available to the public for download.  HAZUS, utilizing GIS systems, is described as a “nationally applicable standardized methodology that estimates potential losses from earthquakes, hurricane winds, and floods.”[28]  Looking to download and examine the software, I found that it requires ESRI’s ArcGIS program to run, and that the FEMA site directs users to ESRI where it can be purchased.  From this, I can assume that the HAZUS program is primarily used by and targeted towards local governments, rather than individuals and homeowners.  Although this makes sense, it again limits the accessibility of invaluable information that can be provided – and even local governments may choose not to pursue the costs of analyzing the public data through GIS mapping (costs of the program and of individuals educated to use the program, time to overlay data, etc.).

Again, based solely off of FEMA’s FIRM maps and HAZUS program, we can see that the accessibility of GIS programs, as well as the communication of risk information, is at issue.  As suggested by Susan Cutter, a Geography Professor at the University of South Carolina, emergency managers should look to community partners such as universities to assist with mapping and analysis needs.[29]  From personal experience, she describes the ongoing partnership between the University of South Carolina and the South Carolina Emergency Management Division, allowing the two to work towards a common goal – students can gain experience, while the organization can utilize the resources produced.[30]  She further suggests that if costs of the program or ability to use a program are at issue (such as ESRI ArcGIS), other mapping tools or platforms may be available.[31]  For example, I downloaded QGIS, a free GIS program rather than the common, but pricey ArcGIS.


Starting with FEMA, and moving towards states and local governments, GIS investment should be prioritized for use in disaster management.  Funds ideally should be directed towards increasing data and improving accuracy of that already existing, towards making GIS programs available for use (or finding assistance through partnerships), and towards promoting the communications of risk assessment with the public.














[1] GIS, National Geographic Society, (last visited Nov. 1, 2016).

[2] Id.

[3] Id.

[4] What is GIS, ESRI, (last visited Nov. 1, 2016).

[5] T.J. Cova, GIS in Emergency Management in Geographical Information Systems: Principles, Techniques, Applications, and Management 845-858, 850 (1999).

[6] Disaster Preparedness and Recovery, Emergency Management, (last visited Nov. 1, 2016).

[7] Alexandra Enders & Zachary Brandt, Using Geographic Information System Technology to Improve Emergency Management and Disaster Response for People with Disabilities, 17 J. of Disability Pol’y Stud. 223-29, 224 (2007).

[8] Phong Tran et al., GIS and Local Knowledge: A Case Study of Flood Risk Mapping in Viet Nam in Disasters 152-169, 155 (2009).

[9] Id. at 153.

[10] Id.

[11] Enders & Brandt, supra note 7, at 224.

[12] Cova, supra note 5, at 856.

[13] Flood Insurance Reform, FEMA, (last visited Nov. 1, 2016).

[14] National Flood Insurance Program: Flood Hazard Mapping, FEMA, (last visited Nov. 1, 2016).

[15] Id.

[16] Flood Insurance Reform – Mapping Flood Hazards, FEMA, (last visited Nov. 1, 2016).

[17] Flood Insurance Reform, FEMA, (last visited Nov. 1, 2016).

[18] Committee on FEMA Flood Maps et al., Mapping the Zone: Improving Flood Map Accuracy 79 (2009).

[19] Id. at 82.

[20] Id. at 79.

[21] Id. at 80-81.

[22] Id. at 81.

[23] Id.

[24] Id. at 80.

[25] Id.

[26] Id. at 91.

[27] Id.

[28] Hazus-MH Overview, FEMA, (last visited Nov. 1, 2016).

[29] Disaster Preparedness and Recovery, Emergency Management, (last visited Nov. 1, 2016).

[30] Id.

[31] Id.