Case Study 2.5: Restoration: A Tale of Two Rivers

While many of the world’s rivers have been badly polluted, there have been a number of instances where such systems have been substantially cleaned up or “restored,” often with sensitive species like salmon returning where once there were none. Unlike lakes, which tend to accumulate toxins and other pollutants, rivers, particularly those with substantial flow, may be able to cleanse themselves quickly if pollution sources can be cleaned up.

We’ll consider two very different examples of river restoration: (1) the UK’s River Thames, which experienced one of the earliest major restoration efforts and has been held up globally as a success story; and (2) the Grand Calumet River and Indiana Harbor Ship Canal (GCR/IHSC) in northwestern Indiana (USA). Although cleanup efforts here are well underway, the GCR/IHSC is a system still suffering from years of chemical pollution.  Before you start, review some of the Background Materials on the each of these rivers presented here.



Background Materials:

To review how pollutants move in surface waters, go to

River Thames

Videos: watch the videos below to get a picture of what the River Thames is like: (the river from source to mouth) (past and present of the Thames)

Basic information on the River Thames:

A web site that provides information on the Thames Tideway Tunnel:

Grand Calumet River/Indiana Harbor Ship Canal

Video: watch this video to get a picture of what the Grand Calumet River/Indiana Harbor Ship Canal environment is like:

Some history of the Grand Calumet and its struggles is provided by this
New York Times article:

Assessment and cleanup of the GCR/IHSC from the US Fish and Wildlife Natural Resource Damage Assessment:

Information on the Legacy Act and progress on cleanup of the Grand Calumet:

An interesting perspective from a member of the Grand Calumet Task Force is given at

Background information about the U.S. EPA’s Great Lakes Areas of Concern program can be
viewed at

Areas of Concern (AOCs) in the Great Lakes in need of cleanup: 


Textbook References and Links:

Exercise 3:  Thames Water Company project website:

Downloadable data and files:
Exercise 4:       River Restoration EX4.txt

Exercise 5:       River Restoration EX5.txt
Johnson 2009.pdf