Korea's dirty battle against urban sewage

We have a crappy problem, literally

Inside a dimly lit basement, a giant machine resembling a submarine sits on one side of a gray cement wall. Inside, wastewater boils away furiously.

Everything that goes down the drain in Suwon, Gyeonggi Province, a city of 1.25 million people, ends up here at the Suwon Environment Affairs Agency.

“The wastewater goes through a chemical treatment to get rid of the smell. The facility is underground, so we can control the ventilation and odor,” says Ryu Myung-gu, chief of TSK, a firm that runs the wastewater treatment plant.

On the ground floor, a repulsive stench hangs thick in the air as a filtering machine spits out a mishmash of toilet paper, hair and food waste -- all smothered in fecal matter.

According to Ryu, dealing with urban sewage is becoming an uphill battle, as more people migrate to cities and flush everything from kitchen waste to pet feces down the toilet.

“All of these are making wastewater more toxic,” Ryu said, seemingly unbothered by the smell.

As urbanization intensifies, the density of organic wastewater, which stood at 128.2 mg/L in 2009, surged to 162.1 mg/L in 2018 at public water treatment facilities nationwide.

As urbanization intensifies, the density of organic wastewater, which stood at 128.2 mg/L in 2009, surged to 162.1 mg/L in 2018 at public water treatment facilities nationwide.

Threat of rising toxicity

Source: Environment Ministry

Unit: milligrams of organic waste per liter of water

TSK's facility is designed to process 160 mg/L of organic waste - a mixture of fecal matter, detergent, soap, fat, grease and food particles. These days, the facility encounters densities as high as 500 mg/L.

When toxicity soars, TSK blows extra air into the wastewater so that healthy bacteria can better thrive and break down organic waste.

TSK’s underground facility, though built in 2005, has undergone a series of upgrades to tackle the wastewater that is becoming more toxic every day.

However, worrisome signs are showing up in other facilities. Most of the water treatment centers, built in the 1990s and 2000s, are becoming too old to keep up.

However, worrisome signs are showing up in other facilities. Most of the water treatment centers, built in the 1990s and 2000s, are becoming too old to keep up.

Aging water treatment centers

25 years old or older

30 years old or older

As a result, water treatment centers are increasingly failing to meet discharge standards.

As a result, water treatment centers are increasingly failing to meet discharge standards.

Wastewater discharged beyond legal limits

Source: Environment Ministry

Unit: cases

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Photos and videos An Jeong-yeon and Lee Eun-soo

By Kim Byung-wook

Yonhap