These links will help you with your PBL research.
http://www.riversofalabama.org/Coosa/COOSA.htm
http://en.wikipedia.org/wiki/Coosa_River
http://www.britannica.com/EBchecked/topic/136455/Coosa-River
http://www.caria.org/
http://www.worldwildlife.org/what/wherewework/sers/WWFBinaryitem16544.pdf
http://www.childersburg.org/ChildersburgHistory.htm
http://wn.com/Coosa_River
