As the famous saying goes, rivers are the cradles of human civilisation. Our ancestors bathed in them, drank from them and travelled with their rudimentary boats across waterways. They also defecated there, urinated there, and used rivers as a convenient way of doing away with their trash. Surprisingly, it wasn’t until the Great Stink of the Thames back in 1858 that real action was taken, in the form of sewage networks, to mitigate water pollution and decrease our reliance on untreated water - thenceforth, the inseparable relationship we once had with rivers faded away from public consciousness. But after sewage disposal was dealt with, another problem, floods, came into the public limelight. For Hong Kong, as some of our urban agglomerations are concentrated in flood-plains, huge swathes of land were often flooded during the occasional rainstorm. As an example, over 1,170 hectares of land (over 23,600 basketball courts!) were deluged by rainwater during Typhoon Brenda. To this effect, the Drainage Services Department was established in 1989, and a rough Flood Control Strategy was completed in 1993. Hence an ambitious flood prevention/attenuation programme with a $10 billion budget was adopted, and between 1997 and 2004, 55km of rivers were channelised (i.e. straightened and having the river bed covered in concrete) in the New Territories. With this, however, came significant environmental ramifications. As over 60% of HK’s rivers were channelised between 1993 and 2003, further ecological damage resulting from habitat loss was inflicted upon Hong Kong’s 140 freshwater fish species; to raise another example, over 14.1 hectares of fish ponds and farmhand was destroyed when a new floodway was built in Yuen Long back in 2006. Fortunately, in recent years, new planning paradigms involving preserving natural habitats and considering the visual impacts of these drainage projects have emerged, as implemented in new projects such as the Kai Tak Nullah revitalisation project. So has the phenomenon of barring residents from river channels ad infinitum out of concern for our safety been reversed: decreased pollution (which we can credit well-managed, separate sewage networks for), landscaped/beautified riverbanks, a return of wildlife (as in the case of Lam Tsuen River) and increased public awareness means that water-friendly activities can be returned to our urban rivers once again, just as our ancestors once lived symbiotic relationships with them. But this time, we won’t be executing our biological functions there! Sources: https://www.legco.gov.hk/yr03-04/english/panels/ea/papers/eaplw0223cb1-1035-3-e.pdf https://www.dsd.gov.hk/EN/Files/Technical_Manual/technical_papers/LD0501.pdf https://www.dsd.gov.hk/Documents/AnnualReports/0405/EN/ch2/ch2.htm https://industrialhistoryhk.org/flood-control-works-yuen-long-area-1960s-2006-negative-impact/
Image Credits: Development Bureau, Hong Kong Gov't
Written by: Yui Hang Cheng