A ground-breaking Combined Sewer Overflow (CSO) trial is underway in eastern China to support a Chinese government initiative to encourage water innovation and improve urban inland river water quality. As part of a national water project, a Hydro International Storm King® advanced hydrodynamic vortex separation system has been manufactured and supplied for a trial on the XiErChi River, an inland river in Chaohu city in the province of Anhui, which is about 250 miles west of Shanghai.
The National Water Pollution Control and Treatment Science and Technology Project, known as "water special", is one of 16 major science and technology initiatives identified to make breakthrough progress in China over the next 15 years.
For the trial to succeed, research engineers from the Shanghai Urban Construction Design & Research Institute were looking for a high-performing primary treatment solution that could reduce Biological Oxygen Demand (BOD), as well as preventing grit, sediments and trash from entering the watercourse during peak storm events.
Manufactured and installed during 2015, the Chaohu City Storm King is now preventing the highly polluting sediments that are re-suspended in sewer water during storm events from being discharged into the XiErChi River.
The CSO project supports the ongoing water quality improvements at Chao Lake, one of China’s five largest fresh-water lakes and a popular tourist destination. Although in past decades high levels of surface runoff and agricultural organic pollution caused eutrophication and silting in Chao Lake, recent treatment work has significantly improved its water quality.
Anhui province is a demonstration area selected for the water projects, which cover improvements to river basin water pollution control, lake eutrophication control and water environment ecological restoration. China has made progress in improving water quality and a key aim is to encourage greater public awareness and engagement, so as part of the project the research team were keen that the local community in Chaohu City should be aware of the CSO installation as it got underway. To support this, the Chaohu Storm King has been constructed in a raised position, so that it can be viewed in a public area to encourage community awareness of water quality improvements.