Peng Guanping, technical director of the sewage disposal systems for the new hospitals, said, "As the disease is highly infectious, our standards are even higher than usual."

He noted that while the normal time for sterilization of medical wastewater is 90 minutes, the new hospitals' disposal systems will allow five hours.

Those standards will not only apply to medical wastewater, as an impermeable membrane will ensure that even rainwater washing through the facilities will be treated.

"Every single drop of water discharged from the two hospitals will be sterilized to make sure it won't cause new infections," Peng said.

Having gained great experience of medical wastewater disposal during more than 10 years in the field, he said the Wuhan project is the biggest challenge of his career. That's because disposal systems on this scale normally take at least 60 days to complete, but this time the work will have to be finished within 10 days.

"As we are facing a totally new virus, we have to be careful and we have to come up with our best plan," he said.