Every excretion flushed in the city of Chicago ends up as fertilizer on midwest farms. Mostly soybeans, IIRC.
A lot of zoos sell their surplus animal dung in big bags called "zoo poo." It's used in home gardens and small scale community farms.
https://bloomsoil.com/about-bloom-soil-amendment/
They also generate 8MW of electricity from burning the methane produced during treatment, which is about a third of their electricity requirement.
Is this meaningfully true? My understanding is that the wastewater is treated and emptied into the Chicago river where it flows toward Missouri. Insofar as that water is rich in organic compounds, it "fertilizes" the fields that draw from that river and its distributaries; however, this model is different than the picture you paint, which sounds more like dumping more-or-less raw sewage directly on fields. If the latter is indeed the case, it's news to me, especially since I understand human sewage fertilizer to be prohibited as a health risk.
https://news.wttw.com/2016/05/24/turning-wastewater-fertiliz...
“What it does is essentially recovers the phosphorous and the nitrogen in the wastewater at the Stickney plant and coverts that into a high-grade, slow-release fertilizer that can be used for all sorts of agricultural applications.”
Yes.
My understanding is that the wastewater is treated and emptied into the Chicago river where it flows toward Missouri.
The clean water goes into the Sanitary and Ship Canal. The solids fertilize fields.
https://mwrd.org/mwrd-biosolids-compost-help-energize-ford-h...
https://www.ocregister.com/2015/02/24/yes-you-can-drink-it-a...