"Beijing's Forbidden City can be at risk of being flooded, but it's not because modern technologies and repairs have deteriorated the drainage （排水）system," Beijing News Radio reported.

The report is in response to a popular online view: The Forbidden City, the royal palace of Ming and Qing dynasties also known as the Palace Museum, has never been flooded throughout its history of more than 600 years. 

Earlier, a video showed ankle-deep water near the Forbidden City's Cining Palace, where the royal women used to live. Some netizens have questioned whether modern drainage repair works have made the system much weaker. 

Di Yajing, an official in control of affairs relating to the site, told Beijing News Radio that the Forbidden City has a complex（复杂的）drainage system. "Rain coming down from roofs was guided to the basement and then to the drains," she said, adding that rainwater would flow from the central of the palace to both sides, and from north to south, due to differences in heights.

"The drains were cleared once a year in springtime in ancient times and nowadays they are cleared three times a year except in winter," the report said. "Although the number of clearing increased every year, it's not modern technology that worsened the ability of the drainage system," the report said. During the clearing process, workers found lots of modern objects such as plastic bottles and bags, even towels and clothing, and these things resulted in the blocking of the drainage system.

In addition, there are plenty of records that have recorded occasions in which the palace was flooded and some roofs or walls were damaged by floodwaters, according to the report. For example, a rain in 1885 led to floodwaters of about 1 meter deep. Every time people would have to find out the place of blockage, clear it and then the drainage system would work well right away.