Department of Earth Science |Northeastern Illinois University

Earth Science 121

Lab Assignment: Stream Discharge Data Collection                                             
(Due at the beginning of class, 5:40 pm, Tuesday, November 21, 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".  Then, in the fourth paragraph under "Introduction", click the link for "Daily Streamflow Data".  Under "Site Location", click "State", and then click "Submit.  Under "State", select "Illinois".  Scroll down, and near the bottom of the page, under "Choose Output Format", select "Table of sites sorted by SITE NAME grouped by COUNTY" (you will have to select the words "Site Name" and "County" from the dropdown menus.)  Finally, scroll down a little further and 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 gives you numerous pieces of information about the watershed (also called drainage basin).  Get to know the watershed by going to the area near the top titled "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


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) (found on the "Site home page")

    d.  Site maps: larger scale map giving the general location in Illinois, and smaller scale map giving the location of the gage on the stream (select "Site Map").  Printing black and white or in color; either is acceptable.

    e.  Period of record: how long the gage has been in place, collecting data (see the "Site home page").

5) COLLECT ONE YEAR'S WORTH OF DISCHARGE DATA

Choose a one-year time period--long ago, recent, or anything in between!  On the "Available Data for this Site" menu, click on "Daily Data" and GO.  Under "Output Format", click "Table".  Go to the boxes for "Begin date" and "End date", 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!  (If you get an error message, that's probably why.)

Click GO.  Print the list (it may be several pages long).  Bring your data to class with you!

© 2006 Laura L. Sanders.  Last updated November 14, 2006.