A dike is opened to let floodwaters run into a 2,000-hectare storage area in Lujiang, Anhui province, on Monday. Local authorities decided to evacuate people within the area and start to use it as the water level in Chaohu Lake downstream reached a historic high. (Photo: China Daily)

The Ministry of Water Resources and the local government of Nanjing have investigated the illegal construction of several restaurants and bars built inside one of the dikes of a main river that runs through the capital city of Jiangsu province.

The five restaurants and bars were built inside a dike on the Qinhuai River located near Yangjiawei Park of Nanjing's Jiangning district. Each of them were built into holes that were about 12 meters deep and 3 meters high on the side of the dike that does not face the water.

The local government demolished all the windows, doors and decorations of the illegal establishments on Sunday night. To avoid possible further damage to the dike, the concrete frames of the buildings were kept.

The Qinhuai, which runs through the main districts of Nanjing, is a tributary on the right bank of the lower reaches of the Yangtze River.

Due to heavy rains and large flows from the Yangtze, the Nanjing government raised the emergency response for flood control of the Qinhuai to the highest level earlier this month.

Experts have been sent to evaluate the damage to the dike, according to the Ministry of Water Resources.

Any violators of China's river management regulations will be severely punished, the government of Jiangning district said on its website.

The holes in the dike were developed in 2012 by Jiangning Urban Construction Group, and the restaurants and bars had been operating in them for at least six years. The group kept one hole measuring about 1,000 square meters to use as a dike patrol management site in 2013. It rented out the rest, about 3,500 square meters, to five restaurant and bar operators.

"Each operator paid nearly 500,000 yuan ($71,400) to the group every year," said one business operator surnamed Liu. "The group had been trying to take back the venues since May 2018, but failed to reach an agreement with some of the operators."

The group knew the buildings were illegal, he said, adding that the restaurants and bars might have had an impact on the solidity of the dike because sometimes he witnessed water seeping out of the walls.

Some of Nanjing's local media reported the illegal constructions in 2014, but at the time the construction group simply promised that it would suspend them.

According to China's river management regulations, houses and roads cannot be built in certain surrounding areas of the dikes. Even the construction of bridges needs to be approved by various administrations to guarantee the safety of the dikes.