Audi Mexico shows how to produce cars completely free of wastewater

Audi through its Mexican production facility has become the world’s first premium manufacturer to produce automobiles completely free of wastewater. The Audi México plant, which opened in 2016, produces the Audi Q5 for the world market. 

At its plant site in San José Chiapa, Mexico, the company is using a new water treatment process that collects 100 percent of the wastewater produced there, purifies it and feeds large volumes of clean water back into the plant’s water supply system. In this way, Audi México ensures sustainable use of the water as a resource and minimises the environmental impact of its car production.

From the paint shop to leak tests – water is necessary in the entire process of automobile production. The wastewater generated at Audi México first undergoes chemical-physical treatment, which neutralises the water and removes particles and heavy metals, from the paint shop for example. This pre-treated water is then further processed together with the remaining wastewater from the site in a biological wastewater treatment plant, where organic components are decomposed. Finally, a combination of ultrafiltration and multistage reverse osmosis separates the remaining contaminants, including bacterial germs and alkalis.

Audi says it reuses the hygienic and high-quality recycled water directly at the site. The concentrated matter from reverse osmosis is evaporated and the dehydrated solids are disposed of.

“We are pursuing the vision of producing cars at all our sites completely CO₂ neutral and free of wastewater. We have reached a major milestone in this respect at our plant in San José Chiapa,” stated Peter Kössler, Board of Management Member for Production and Logistics at Audi AG. “As an automobile manufacturer, we have an obligation to ensure the careful and environmentally compatible use of valuable resources such as water. With the new reprocessing method, we are also making a significant contribution to combating water shortages in Mexico.”

Audi México uses the treated water as process water in production and to irrigate the green areas on the plant grounds. With this innovative process, it is saving around 100,000 cubic metres of water per annum, equivalent to about a quarter of the plant’s total requirement. In the long term, the company actually plans to save more than 300,000 cubic metres of groundwater every year.

“With the new wastewater treatment system, Audi is taking an important step towards an autonomous water cycle,” said Rüdiger Recknagel, Head of Environmental Protection at Audi AG. “By the end of 2025, we want to reduce the Audi Group’s environmental impact by 35 percent per car produced compared with the reference year 2010. This measure brings us closer to that goal.”

To further reduce the use of groundwater, a reservoir with a capacity of 240,000 cubic metres is located on the site. It fills up during the rainy season of approximately six months from April to September. The rainwater is collected and treated and also used in the plant. “Audi México is the youngest site in the Audi Group. We are all the prouder to play a pioneering role in the sustainable use of water as a resource,” said Alfons Dintner, chief executive of Audi México.

As part of its commitment to the environment, Audi México has also planted more than 100,000 trees and installed 25,000 septic tanks on an area of 100 hectares in the neighboring municipality of San José Ozumba. In the rainy season, up to 375,000 cubic meters of water are returned to the groundwater there each year.