Frogman braves the dark to clear sewers

Despite the dangers, sewerage workers need to unblock city drains before the floods arrive

Before beginning his descent underground, Xi Sheng puts on a gray diving suit weighing 35 kilograms with the help of two people. The suit is made of rubber, and attached to a safety rope. On most workdays, Xi wears the suit for two to three hours to work in the sewers.

People like Xi are called "sewer frogmen". Unlike the usual frogman who wears a waterproof suit and flippers, carries oxygen tanks and works in deep waters, the sewer frogman works in the sewerage system all year round to clear drainage pipes in urban areas.

"I need to stay in sewers full of fetid sewage and garbage for two to three hours when I am working. I was a little scared at first, but now I am used to the working environment," said Xi, a native of Shanxi province.

Two years ago, the 28-year-old started to work as a sewer frogman for a company based in Dalian, Liaoning province. Xi is the most experienced of the three sewer frogmen working in the company.

"A sewer frogman works in the sewers for about 400 hours in a year," he said.

The sewage is usually foul and corrosive, so the material of the diving suit needs to be of high quality. Xi's diving suit cost more than 300,000 yuan ($43,300).

Along with Xi's diving suit is a helmet similar to a gas mask.

However, instead of connecting an oxygen tank to it, an air outlet, as thick as a wrist, is connected to the helmet and it stretches up above ground to provide him air. There is also a communication device inside the helmet through which the frogman can regularly report real-time conditions to colleagues on the ground.

"If we stay in the sewers for over 10 hours, we will need to wear a diving suit with iron headgear, which weighs about 100 kg and can allow us to stay in the sewers for a long time," Xi said.

Recalling the first time he worked in the sewers, Xi said he felt depressed, nervous and lonely as a frogman needs to crawl into the dark sewers to clear blockages.

"The narrowest pipe that I have to crawl through only has a diameter of 60 centimeters," he said.

"People in this job need some guts and courage. They also need professional training, or their lives may be in danger."

Almost every year, there will be news about some sewer frogman's death because they were unfamiliar with the circumstances in the sewers.

Sewers are full of stinking sewage and some debris such as bricks, stones, weeds and toilet paper. In the sewers, the frogmen can see nothing and have to feel their way around with their hands. They must carefully learn the structure of the sewer system before entering, he said.

"We have to be especially careful about the flow rate of sewage water. If the rate is too fast, we may be washed down by the sewage in the sewer, and that can be pretty dangerous," Xi said. To avoid such situations, frogmen sometimes tie lead weights of 20 kg to their suits.

"Methane gas in the sewers is another threat," Xi said. Methane gas is formed from the decomposition of garbage.

With all these dangers, Xi is very cautious when entering the sewer. He understands the structure of the sewers, and measures the amount of methane gas and the water flow in the sewers with devices before making his way down.

Xi chose to work in the sewers because of a short-term training course in which he learned the relevant skills after graduating from high school. The other reason is because of the high wages. "You can earn 4,000 to 5,000 yuan each time by working in the sewers, and the highest wage I've earned is 9,000 yuan."

Sun Jianxun, 27, the owner of the company that Xi works for, is also Xi's schoolmate. After quitting his sales job in a pipeline maintenance enterprise, Sun founded the company.

Sun said the job of sewer frogmen is important because they ensure the water in the sewerage system can flow properly when there are floods.

Although the work that they do brings in more money than other jobs, Sun said it is also quite tiring and he hopes that sewer frogmen can be replaced by robots in the future.