Study finds room for improvement in South Korea's polluted river basin

July 12, 2018

A new Portland State University study shows that even though water quality has improved in South Korea's Han River basin since the 1990s, there are still higher-than-acceptable levels of pollutants in some of the more urbanized regions in and around the capital Seoul.

The study by Heejun Chang, a geography professor in PSU's College of Liberal Arts and Sciences, and Janardan Mainali, a Ph.D. student in geography, was published online in the Journal of Hydrology in June. It was supported by a grant from the National Science Foundation.

The study used spatial data from the early 1990s through 2016 to examine seasonal water-quality trends in the Han River basin, the largest and most populous river basin in South Korea. The river had become synonymous with pollution as factories, farms and city sewer systems poured waste into its waters. But ahead of the 1988 Seoul Olympics, the government launched efforts to begin cleaning it up.

The study examined the relationship between water quality -- as measured by total nitrogen (TN), total phosphorus (TP), chemical oxygen demand (COD) and suspended soil particles -- and topography, population density, soils, and land cover such as changes from forest or agricultural use to urban land.

The study showed that the water quality generally improved within the Seoul metropolitan area but declined in rural areas from the early 1990s to 2016.

Some of the urbanized regions still had higher-than-acceptable concentrations of nitrogen, phosphorus and COD. Even though wastewater treatment plants were built, the study suggests that the population growth in suburban areas may have outpaced the proper treatment of wastewater as well as increasing runoff or "non-point source" pollution.

Among the findings:

Chang, who also serves as a faculty fellow at PSU's Institute for Sustainable Solutions, said that governments and agencies need to be proactive in ensuring water quality is a priority, particularly in suburban and developing rural areas, by imposing more stringent regulations, implementing best management practices and creating natural buffers.

"Nature-based solutions have shown to improve water quality in the long run," he said.

Portland State University

Related Water Quality Articles from Brightsurf:

A watershed moment for US water quality
A new federal rule that determines how the Clean Water Act is implemented leaves millions of miles of streams and acres of wetlands unprotected based on selective interpretation of case law and a distortion of scientific evidence, researchers say in a new publication.

'Pregnancy test for water' delivers fast, easy results on water quality
A new platform technology can assess water safety and quality with just a single drop and a few minutes.

New process could safeguard water quality, environment and health
Swansea University researchers have developed a new way to quickly find and remove wastewater pollutants, which can reduce their impact on the environment.

23 years of water quality data from crop-livestock systems
Researchers summarize runoff water quantity and quality data from native tallgrass prairie and crop-livestock systems in Oklahoma between 1977 and 1999.

Lessening water quality problems caused by hurricane-related flooding
June 1 is the start of hurricane season in the Atlantic, and with 2020 predicted to be particularly active, residents in coastal regions are keeping watchful eyes on the weather.

Control of anthropogenic atmospheric emissions can improve water quality in seas
A new HKU research highlighted the importance of reducing fossil fuel combustion not only to curb the trend of global warming, but also to improve the quality of China's coastal waters.

Pharma's potential impact on water quality
When people take medications, these drugs and their metabolites can be excreted and make their way to wastewater treatment plants.

Study: Your home's water quality could vary by the room -- and the season
A study has found that the water quality of a home can differ in each room and change between seasons, challenging the assumption that the water in a public water system is the same as the water that passes through a building's plumbing at any time of the year.

Researchers create new tools to monitor water quality, measure water insecurity
A wife-husband team will present both high-tech and low-tech solutions for improving water security at this year's American Association for the Advancement of Science (AAAS) annual meeting in Seattle on Sunday, Feb.

How anti-sprawl policies may be harming water quality
Urban growth boundaries are created by governments in an effort to concentrate urban development -- buildings, roads and the utilities that support them -- within a defined area.

Read More: Water Quality News and Water Quality Current Events is a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for sites to earn advertising fees by advertising and linking to