- Imagine that in your future work as an executive for an insurance company that
you have been reassigned to head up the Fargo, North Dakota office of your company,
Denyallclaims Insurance, Inc. You are aware that in 1997 the Red River of the North, which
runs through Fargo, crested at the highest level recorded in this century, and you are
concerned about buying property and living in the area of Fargo. One of the other
executives in your company has an uncle that lives in Fargo, and he assures you that while
flooding was severe in 1997, this was a 250 year flood, and such a flood will not occur
for another 250 years! You know from taking this class that his statement is
hogwash, so you decide to check out the discharge history of the Red River in Fargo on the
internet. Because you took a course in natural disasters, you know that if you visit
the web site of the U.S.G.S. Water Resources Division:
http://water.usgs.gov/nwis/
you can obtain discharge data from thousands of gaging stations throughout the United
States. Go to this web site and do the following:
On the upper right-hand side of the page are boxes that you can set to
take you more directly to the information you want. Under the line
that says "Data category", use the down arrow next to the box
to change the box to read "Surface Water".
Under the line that says "Geographic Area", use the down arrow
next to the box to change the box to read "North
Dakota". Then, click on the "Go" button. This
will take you to the North Dakota surface water page.
Next, click on the button that says "Stream Flow" from the
selection of buttons on the left-hand side of the page. This will take
you to the Daily Streamflow for North Dakota page. Here we need to
specifically search for the Data we want. About the only
information that we know is that we are looking for information on the
Red River of the North. Since each river is a different "hydrologic
unit", we will use this as our search criteria. So, click on
the box next to "Hydrologic Unit" to place a check mark in the
box, then click on the "Submit" button.
On the page that comes up, there is a box from which we can choose the
hydrologic unit we are looking for. In this case, find and select
the unit called "Upper Red", then scroll down and click on the
"Submit" button. The search should then return results
for all gaging stations on the Upper Red River. In this case, you
will find 3 possible choices. The one we want is "RED RIVER
OF THE NORTH AT FARGO, ND", which has the station number - 05054000. Click on this
station number. This will bring up
the page for the Fargo gaging station. On this page make sure that
it says "Surface Water - Daily Streamflow" in the box next to
"Available Data for this site". Note that records are
available from 06/01/1901 to 09/30/2000.
- You want to look at this data over a shorter period of time, so
scroll down and next to where it says "Retrieve Data
from" type in 1968-01-01 and in the
"to" box type in 1998-01-01,
to get a graphs showing daily discharge over this 30 year period. Make sure that you
have selected the buttons to select an output format of Graph and arithmetic
scale, rather than log scale. Then click
on the "Submit" button. The site is rather slow, but eventually a
graph will appear that shows discharge on a daily basis versus time for the 30 year
period. Look at the graph. Floodstage for this gaging station is about
3500 ft3/sec. Over this 30 year period, how many times has the Red River
exceeded flood stage? In what year did the highest discharge occur, and what was the
value of that discharge?
- Notice that there seems to be a periodicity to where the peaks of high discharge occur
on the hydrograph (that is the distance between peak discharge points are approximately
equally spaced). In order to better understand what may be the cause of this
periodicity, and perhaps the cause of the flooding, click on the "Back"
button to return to the data retrieval page. Now ask to retrieve data over a
shorter period of time (5 years), this time use range between 1978-01-01 to
1984-12-31.
Click on the "Submit" button again, and look at the graph that is
eventually displayed. What is your best estimate the approximate month or months in which
the peak discharge occurs in each year of this 5 year period? Knowing that North
Dakota is in the northern part of the United States, why do you think that the peak
discharge occurs in this month or range of months?
- To find out more about floods on the Red River of the North go to the
Fargo Flood
Home Page:
http://www.ndsu.nodak.edu/fargoflood/
then page down and select the link - "Flood Information for
Fargo".
Now answer the question - What makes the Red River Valley so prone to flooding?
- Is there any information at this web site that suggests that nay
floods have occurred at Fargo since the 1997 flood? If so, when
was the latest flood and how severe was it? (Note: to answer
the question about the severity of the any recent flood, you might
want to consult flood hydrographs for the 1997 and any possible more
recent flood and compare them with each other and to the flood
frequency diagram for the Red River at Fargo that appears in your
lecture notes.)
- What precautions should you take in choosing your home and home site
in the Fargo area if
you decide to move there to head up the Denyallclaims office in Fargo?
Is there any information or links on the Fargo Flood Home Page that
would help you in making this decision? If so, describe any
information that is available.
- From what you have learned by visiting the web sites for this
assignment, how to you respond to your uncle who said that severe
flooding would not occur for another 250 years?
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