L e a r n i i n g A b o u t F l l o o d Z o n e s U s i i n g A r c G I I S O n l l i i n e
Your Name: _____________________
Summary
This activity uses ArcGIS Online, a Webbased Geographic Information System
(GIS) ( www.arcgis.com
) as a tool for analyzing the geography and science of water from a spatial perspective. This activity focuses on flood zones.
Detail
This activity is written for upper secondary/university level but can be used at the lower secondary level, and can even be modified for primary levels.
It can be used in formal or informal educational settings and in an independent or whole-class format.
Time estimated: 1 class period of 50
Map of flood zones in Nebraska in ArcGIS Online. This is one of the maps created and investigated in this activity. minutes. No previous experience with GIS is necessary but (1) the geographic perspective is important, and (2) a background in the topic investigated would be helpful; at a minimum, a short discussion on the processes and phenomenon studied in each investigation should be held at the beginning; such as
“What is a flood zone? What influences the shape of a flood zone? What influences the severity of a flood? What is a 100 year flood?“
Computer requirements: Web browser, Internet connection. Can be run in a computer lab setting, with dedicated lab computers or students bringing their own tablets/laptops/devices, or with 1 computer in front of the class with a projector.
Introduction
Water is a spatial subject: It can occur in solid, liquid, and gas phases on our planet and can easily move between these three states. It moves through oceans, rivers, wetlands, and glaciers, and through the hydrologic cycle at different rates. It is affected by long-term climate, everyday weather, hurricanes, landforms, and air pressure. It has been channeled into settling ponds, water treatment plants, fields, irrigation ditches, drainage ditches, canals, reservoirs, and through many other means by humans. It acts as a change agent above, on, and below the surface of the Earth, affecting such phenomena as crop yields, aquifers, erosion, floods, stream sediment, soil chemistry, weathering, and much more. It operates on a scale from local to global. Because water exists, moves, and acts at different scales and
Learning About Flood Zones Using ArcGIS Online - Page 1 of 4
Author: Joseph J. Kerski
– jkerski@esri.com
Copyright © 2012, Esri. http://edcommunity.esri.com

affects so many other phenomena, the geographic perspective is critical to understanding it. And, GIS is a very useful tool in which to study water in all of its forms, processes, and aspects.
Watch the movie “geographic reflections on water”: http://youtu.be/ntJvY4LixqQ
Name 3 connections between water and geography.
Because of these and a whole host of other factors, the geographic perspective is critical to understanding water. GIS allows the geographic perspective to be applied to the study of water, and
ArcGIS Online provides a toolkit and rich set of data that allows you to study water right away.
ArcGIS Online Investigation
This investigation uses ArcGIS Online, on http://www.arcgis.com
.
Investigating Flood Zones
At ArcGIS Online ( www.arcgis.com
), click on “map.”
Using the Add button, add “FEMA 100 Year Flood Zones in the USA”. Do some research on a “100 year flood zone.” What is meant by the term “100 year flood”?
At the USA scale, examining the counties, what do the 2 different colors of the counties indicate?
Find and zoom to North Platte,
NE, as shown at right. What two rivers meet at North
Platte? What part(s) of town is most prone to flooding?
Expand the data layers and turn off the “counties with flood data available” layer, as shown below.
Learning About Flood Zones Using ArcGIS Online - Page 2 of 4
Author: Joseph J. Kerski
– jkerski@esri.com
Copyright © 2012, Esri. http://edcommunity.esri.com

Zoom out until you see flood data adjacent to areas with no flood data, such as in the map pictured on the previous page.
Using the Search box in the upper right of the map, search for Cairo, IL. What two rivers meet at Cairo?
Change the base map to topographic and make it semi-transparent so you can see the streets of Cairo along with the 100 year flood zone. How much of the town of Cairo is inside the 100 year flood zone?
Why is Cairo so prone to flooding?
Why do you think Cairo never developed into a large city, despite its strategic location?
Follow the Mississippi River upstream on your map to St Louis. What two major rivers flow together just north of St Louis? Name two reasons why St Louis developed into a much larger city than Cairo.
Name at least two other cities in the USA that are on the confluence of two major rivers. Did they develop into large cities? Why or why not?
Find and zoom to Owensboro, KY.
How much of Owensboro, Kentucky is inside the 100 year flood zone?
How much of your own community is inside the 100 year flood zone?
Learning About Flood Zones Using ArcGIS Online - Page 3 of 4
Author: Joseph J. Kerski
– jkerski@esri.com
Copyright © 2012, Esri. http://edcommunity.esri.com

Synthesis
Name three things you have learned about flood zones through any of the above investigations.
Name three things you have learned about GIS through these investigations.
How has the spatial perspective about flood zones influenced your understanding of them?
If time permits, use the presentation mode in ArcGIS Explorer Online to create a presentation of your own choosing where you explain what you have learned about a specific aspect about flood zones. Give your presentation to your peers, save it, and share it with others.
Additional Explorations
You have explored a few aspects of flood zones from a spatial perspective, but much more could be done. Write your own question about flood zones, investigate it, and answer it!
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Learning About Flood Zones Using ArcGIS Online - Page 4 of 4
Author: Joseph J. Kerski
– jkerski@esri.com
Copyright © 2012, Esri. http://edcommunity.esri.com