In Mexico, fears a new plant will kill wastewater farming

[...] rather than welcoming the prospect of cleaner water, angry farmers are demanding the government honor an 1895 presidential decree granting them the right to the capital's untreated sewage, which they see as fertilizer-rich, if foul, irrigation water.

According to Fernando Sanchez, a 37-year-old opponent of the plant, corn fields here yield an average of 15 tons per hectare (6 tons per acre) and some produce as much as 18 tons (7.3 tons).

In brochures promoting the plant, which is in its testing phase and expected to come online later this year, the commission called the use of untreated sewage for farming "a public health problem."

The sewage smell is faint in most places except near the Endho reservoir, where a fetid stench permeates homes and makes residents ashamed to invite outsiders to visit.

[...] there are also plots of prohibited, ground-hugging produce such as cauliflower, broccoli and cilantro, all of which flow from the valley to Mexico City's Central de Abastos wholesale market and from there to street stalls, taco stands and dinner tables.

[...] they often wash their hands in the brown water before settling down to eat lunch in the fields.

Christina Siebe, a geologist at the National Autonomous University of Mexico who has spent decades researching farming in the Mezquital Valley, said while there are obvious problems with wastewater farming, it can reduce demand for scarce freshwater resources, keep organic waste from ending up in rivers and oceans, and recycle nitrogen, phosphorus and organic material.