I have a septic system because I live out of the city limits, but I may just start going into town and crapping on the sidewalk since I found out that is what my parents did growing up in the early 1900's.There is a poster here named Septic. Septic systems are modern day outhouses in the sense the systems puts the waste in the ground. Yet, when done correctly, there is no contamination to the water supply.
I bet you can figure out why that is. If you can, you can also figure out why it is different and better than openly defecating.