The annual exodus of migrant workers returning home for the Spring Festival is causing a major strain on urban services and disrupting many urban residents' lives.

"The Spring Festival is creating a severe shortage of sanitation workers in Beijing," said Guang Hong, the owner of an outsourcing company that works with government agencies to clean residential streets in the capital.

Guang is proud to be an exception by keeping all his employees at work for the Spring Festival. He hires more than 300 people, mostly migrant workers in their 50s and 60s.

They work for roughly 1,500 yuan (US$228) a month, without social security or other occupational insurances. Guang said the salary is above the market average, which is around the minimum monthly wage of 1,160 yuan.

"We managed to motivate the employees to do extra work for the same pay during the holiday, because the company has good personal relations with them," Guang said.

Migrant workers in cities often end up with undesirable and low-paid jobs, such as housekeeping and street cleaning.

Urban residents, who have long enjoyed the convenience and largely taken it for granted, are now beginning to see the value of migrant workers in a new light.

They are finding their favorite breakfast stands closed, and coal for home heating now unavailable. And they are facing fewer choices and rising prices for those services still available.

For example, many companies providing household or carwash services, have raised prices due to strong demand but fewer workers.

Particularly under strain are the country's couriers, which have to cope with the Spring Festival peak season with only a small fraction of their normal manpower.

The effects are evident. Many vendors on taobao.com, a popular online-shopping website, stop selling during the festival and put up notices telling netizens that goods cannot be delivered during the holidays.

Zheng Yongcai, director of the Beijing branch of Yunda Express, established in Shanghai in 1999, said the volume of express services is expected to double during the Spring Festival as 80 percent of the company's employees are returning home. Most of Yunda's staff members are migrant workers from all parts of the country.

Zheng said employees staying at their posts will have to work harder and assume responsibilities usually taken by several people.

"We are under the dual pressure of extra volume and increasing customer demands for timely and safe delivery," Zheng said.

Those who stay for the holiday will receive double or triple pay as compensation for their overtime, according to Zheng.

The mass departure of migrant workers at the end of the year is a longstanding problem that has increasingly greater effects on urban residents' daily lives, said Lu Huilin, a sociologist at Peking University.

Although they usually take up menial jobs such as milk or newspaper delivery, their work is an important part of urban life.

"It is a sad fact that people only notice their existence and contribution by the absence of the services they provide," Lu said.

The problem exists because migrant workers cannot enjoy normal family life in their host cities. And job instability caused by their annual mass departure will hurt their own interests, according to Lu.

"The urbanization we talk about in China today is an inflated concept. Only when migrant workers can live in affordable apartments and send their children to school in their host cities, instead of leading a split life, can we talk about urbanization in the real sense," Lu said.