Twenty-one lives were lost in the collapsed subway tunnel construction site in Hangzhou, capital city of east China's Zhejiang Province, in mid-November. It was the deadliest subway construction accident in China's history.

Subway has become a top choice for urban transportation because of its high speed and comfort. In recent years, Chinese cities have gone into a frenzy of track construction. Subway transportation is fully fledged in cities such as Beijing, Shanghai, Guangzhou and Nanjing, and is under construction in cities including Hangzhou and Chengdu. An increasing number of cities are applying to construct subway systems.

As subway lines stretch, accidents follow. Prior to the Hangzhou subway collapse, safety accidents had occurred in Beijing, Shanghai, Nanjing, Guangzhou, Shenzhen and Suzhou.

Overly rapid subway construction has derailed quality control. The factors that have led to accidents in subway construction are similar to other infrastructure projects, that is, hasty construction and insatiate desire for low costs.

Under loose supervision, subway project contractors have put production safety in the backseat in pursuit of speed and profit, threatening workers' lives.

Recently, China announced a 4-trillion-yuan ($586 billion) stimulus package to boost domestic demand and promote stable economic growth. Infrastructure construction is a top priority. In the next two years, more public infrastructure projects will be put on the agenda and track construction will enter a period of much faster development.

If these safety problems are not tackled, accidents will continue to plague new infrastructure construction projects and this will severely hamper the development of a harmonious society.

So the exigency for now is to reinforce production safety legislation and ensure the laws are strictly enforced.

The Hangzhou subway collapse has sounded an alarm bell for construction projects nationwide. Urban transportation in China is still underdeveloped, and will be further expanded in the future. Ineffective management or corruption in such major projects as subway construction will make the public worry about production safety, and question the governance capacity of the government.