Department of Earth Science |Northeastern Illinois University

Earth Science 121

Lab Assignment: Stream Discharge Data Collection                                             
(Due at the beginning of class, Tuesday, April 4, 2006)

In this homework assignment, you will locate and print out one year’s worth of discharge data for a stream gage in Illinois.   We will work with the data in class.

1) FIND THE SOURCE OF ILLINOIS STREAM GAGE DATA

Keep a map of Illinois handy--a road map is fine, or you can use one of the maps in the classroom.  Go to the USGS web site http://water.usgs.gov/.  Under "NWIS Web Water Data", click “Surface Water”, and then click  “Streamflow”.  Under “Site Location”, click “State”, and then click “Submit”.  Select “Illinois”, and under “Choose Output Format”, select “Table of sites sorted by SITE NAME grouped by COUNTY” (you’ll have to select the words “Site Name” and “County”.)  Then, click the “Submit” button.

This will give you a list of all the stream gages in Illinois, grouped by county.  (Long streams will flow through several counties, so you may choose to click "Back" and instead of selecting "county", select "hydrologic unit".  That will show you all the gages on each stream no matter what county they are in.)

2) BROWSE THE DATA AVAILABLE ON THE WEB.

Pick any stream gage, and click on the Site Number.  This will take you to a site specifically for that particular gage.  For each gage, it tells you the period of record—in other words, how long the USGS has been keeping records at that site, and the drainage area--the area of the drainage basin for the point on the stream where the gage is located.   Get to know the drainage basin by going to “Available data for this site” and selecting such choices as “Station Site Map”, “Station Home Page”, and “EPA Surf Your Watershed” (click GO to visit each of these pages).

3) SELECT A STREAM AND GAGE

Choose a stream and gage that seem interesting to you.  Try to pick a stream and gage that nobody else in the class will choose!

4) RECORD IMPORTANT INFORMATION ABOUT THE GAGE
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Find and record (to hand in) the following information:

    a.  Stream name
    b.  Location of gaging station (the town/city, the county, and the latitude/longitude)
    c.  Drainage area (square miles) (see Step 1, above)
    d.  Period of record (see Step 1, above).

5) COLLECT ONE YEAR'S WORTH OF DISCHARGE DATA

Choose a one-year time period, as well--long ago, recent, or anything in between, as long as it's one year.  On the “Available Data for this Site” menu, click on “Daily Streamflow” and GO.  Under “Choose Output Format”, go to the boxes in the “Retrieve data from” line, and enter the beginning and end of a one-year period.  Be sure to use the correct format (YYYY-MM-DD).  Also, be sure that the dates you enter fall within the period of record!

Select “Tab-Separated Data”, select “Display in Browser”, and then click the Submit button.

Print this list (it may be long--7 pages or more).  Bring your data to class with you on Tuesday!

© 2006 Laura L. Sanders.  Last updated March 28, 2006.