Nightlife noise tests residents' tolerance, reports Zhou Wenting in Shanghai.

At 9 pm on July 4, a scorching summer day, more than 1,000 Westerners packed into a 5-meter-wide, tree-lined street chatting and laughing as they sipped drinks on Yongkang Road in Shanghai's Xuhui district.

The 50-meter-long street, a popular haunt for expatriates and located in the former French concession, is bounded on both sides by old, three-story residential buildings, the first floors of which have been converted into about 40 bars.

However, this is proving to be a headache for the locals. The buildings have poor sound insulation and those living on the upper floors have complained about the noise levels for the past year. Some have become so exasperated that they have emptied buckets of water onto the crowds below in an attempt to disperse them.

"Entertainment and nightlife are important components of successful cities and conflict between different communities is a natural consequence of a great, rising city that's not only a center for business, but also for fun and culture," said J. T. Singh, a Canadian "urban explorer and city identity expert" who has lived in Shanghai for six months.

The 40 bars along Yongkang Road have become popular watering holes for expats in Shanghai, but residents complain that the noise is making their lives unbearable. Ri Yi for China Daily

The city is home to nearly 150,000 foreign permanent residents, a number that seems certain to increase, and some experts believe the problems of integration are like to become fraught unless entertainment districts are specifically designed to minimize conflict between the groups or the locals and expats reach some sort of compromise.

Joshua Miller works for a design company in Shanghai. The young Briton said he comes to Yongkang Road regularly after work to grab a beer and talk with friends. "We love this old street. There are traditional grocery stores and shoe shops here and we don't need to dress up like we would if we were going to fancy bars on the Bund. It's very Shanghainese here, people feel comfortable and relaxed," he said.

The presence of 200 French nationals in Ming Yuan Century City on Middle Fuxing Road, a high-class neighborhood nearby, inspired five compatriots to open Yongkang Road's first bar, Le Cafe des Stagiaires, in November 2011.

An influx of foreigners followed and many opened businesses. "We have managers from Australia, France, Italy, Belgium and the United States, Around 90 percent of the bars were opened by foreigners," said Chi Zhihui, general manager of Shanghai Paifeng Yongkang Business Management Co, which works to attract businesses to the area.

The revelry usually begins at around 6 pm. As more people arrive, they spill out onto the street, occupying the tables and chairs placed outside each bar.

"People come to have a few beers, meet their friends and enjoy a chat. They feel at home here," said Benjamin Blaise, a partner at Le Cafe des Stagiaires.

The voices of the patrons were drowned out by the music, forcing them to speak more loudly. Up above, most of the second- and third-floor windows were closed and the ceiling fans were working flat out.

Statistics from the local neighborhood committee show that Yongkang Road has more than 5,300 residents - roughly 1,500 of them are aged 60 or older, while 37 are 90 or older.

Dozens of mopeds lined both sides of the street, leaving barely enough room for cars to squeeze through. The locals said there used to be two lanes of traffic, but the road is now often blocked by the revelers and their mopeds and residents are driven to distraction by the repeated blaring of car horns.

Two inspectors from the neighborhood committee who were patrolling the road said their job is to put the mopeds in orderly rows and to ask people to move when vehicles try to pass. However, their remit does not involve noise pollution or control.

The noise continues until midnight most evenings, according to residents, although Chi said the bar licenses stipulate a closing time of 10 pm.

"We can't drive our customers away, but what we can do is stop taking orders from 10 pm. Still, we can't control when they leave the restaurant," said one waiter, who asked not to be named.