Heatwave on the Han River... Seoul Metropolitan Government strengthens monitoring of algae and odor-causing substances

Seoul's rapidly warming Han River is prompting the city to intensify monitoring and treatment of water quality in a bid to combat rising levels of algae and odor-causing substances. According to Seoul's latest report, the river's water temperature soared from an average of 24°C last July to a maximum of 29°C by May 5th. As water warms, algal growth accelerates, increasing the likelihood of the production of foul-smelling compounds like 2-MIB (2-methylisoborneol) and geo-smell.

In response, Seoul is operating its own alarm system for these odor-causing substances, categorizing them into 'concern, caution, and alert' levels. Testing will be increased from once a week for 'concern' to daily 'caution' and twice daily for 'alert' stages. The city will also bolster its ozone and activated carbon treatment in the purification process to maximize the removal of these substances.

Additionally, they will shorten the time spent on cleaning activated carbon to ensure removal of small organisms that may persist in the water even after treatment.

Seoul will continue to monitor 31 sewage treatment facilities over the coming weeks, with daily inspections leading up to the final water quality check. As Typhoon 'Dolpin' and 'Chanhom' make landfall, a prolonged heatwave is possible, meaning Seoul's water management teams will be on standby to adjust their response plans as needed.

In related news, the Central Emergency Management Agency reported a surge in heat-related illnesses, with the number of patients rising from 202 to 2,089 since the beginning of the heatwave. Among these cases, three individuals have died. One such tragic incident involved an 81-year-old woman in Seoul's Gangnam district who was found unconscious in her home by a caregiver.