The piers were covered by 50,000 bamboo mats to reduce the effect of dust and stones released by the explosion. More than 1,300 tires and 300 tons of steel plates were put under the deck to alleviate the shock wave.

"Though lots of work has been done to protect the neighboring environment, local residents' daily lives will still be influenced to some extent," said Gong Chenglin, deputy director of the headquarters in charge of the explosion.

"Because some roads will be closed during construction of the tunnel, people may need to spend more time in traffic," Gong said.

Qiu Xiaoyun, who lives not far from the explosion site, complained that she now needs to spend twice as long to go to work.

"The viaduct was one of the city's main traffic routes. Many people's daily lives are deeply influenced by the planning," said Qiu.

Ma Jian, a local resident, said that many people have been inconvenienced by the change of many bus routes.

He also said that the viaduct was too short-lived to be demolished after serving for only 16 years.

"It's a huge waste of resources, and I feel sorry for the viaduct," Ma said.

According to Zhou Fang from the Jiangsu Academy of Safety Science and Technology, a viaduct can normally be used for at least 50 years.

Zhao Jingfu, director of the Nanjing urban planning bureau, admitted that city planning did not have enough foresight when the viaduct was built in 1996.

"But 20 years ago, no one expected that the number of cars in China would develop at such a speed," said Zhao. "In the 1990s, people even received an allowance from the government to encourage the car industry."

Zhao said that a detailed and better plan has been made, adding that the tunnel will be put into use before August 2014, when the second Youth Olympic Games will be held in Nanjing.

Though many people have claimed that new construction for the games - including the viaduct demolition - has resulted in extravagance and waste, the local government denied the accusation.

Ding Ming, deputy director of Nanjing's publicity department, said that the demolition was planned in 2006, four years before Nanjing won the right to host the games.

"Some local governments have spent lots of money to host sports games. That money can benefit more people if it is used to improve residents' livelihoods," Jing Yishan, a well-known media practitioner, was quoted by the Beijing News as saying.

"The construction of the facilities for sports games must be approved under strict procedures and be monitored carefully," said Jing.

Chen Wen, a Nanjing resident, also said that a "lifelong responsibility system" should be built to urge government officials to be cautious when they are involved in urban planning to effectively avoid extravagance and waste.

Another three viaducts in downtown Nanjing will also be demolished in the near future due to their limited transportation capacity, the bureau said.