Ins and Outs of Roman Water: Everyone knows about the aqueducts that brought water into Rome, and they are very well documented on the Internet. The aqueducts are, in fact, so well covered on the web that it is difficult to find the really useful sites. Equally monumental, but less well known, was the system of cloacae that took wastewater and excess rainwater out of Rome and made lower parts of Rome, like the forum and the campus martius, habitable. The cloacae are also less well documented on the Internet. Here are a few sites on the ins and outs of Roman water:

Lacus Curtius -- Roman Waterworks:

http://www.ukans.edu/history/index/europe/ancient_rome/E/Gazetteer/Periods/Roman/Topics/Engineering/waterworks/home.html

Roman plumbing:

http://www.theplumber.com/pom.html and

http://www.theplumber.com/eng.html

Cloacae:

Platner: http://www.ku.edu/history/index/europe/ancient_rome/E/Gazetteer/Places/Europe/Italy/Lazio/Roma/Rome/.Texts/PLATOP*/Cloaca_Maxima.html
Smith:  http://www.ku.edu/history/index/europe/ancient_rome/E/Roman/Texts/secondary/SMIGRA*/Cloaca.html
Lead pipes and the fall of Rome:
http://www.nipissingu.ca/department/history/muhlberger/orb/lead.htm
(Or maybe it was the sugar syrup:
http://itsa.ucsf.edu/~snlrc/encyclopaedia_romana/wine/leadpoisoning.html )
And Finally, the poop about Thomas Crapper:

http://www.theplumber.com/crapper.html