The São Paulo water utility opened two high-tech offices and plans to open another later this week.
The winner of the 10-year contract will be responsible for upgrading, operating and maintaining two wastewater treatment plants in the capital of the Mexican state.
The country hardest hit by drought in the region secured badly needed funding for water projects.
Authorities add invoices and water and mining concessions, among others, to a list of instruments that can now be held in securities depositories.
Proceeds from the sale of water infrastructure assets at the Chilean copper mine would help fund a US$2.7bn expansion, while lowering the project's capital costs.
The company will invest some US$4mn in the project.
The approval is part of the drafting of a general water bill for the country.