Hong Kong’s Lai Chi Wo river is ecologically unique. Stretching 2.6km long, the river boasts 45 different freshwater species, and is home to the most extensive mangrove and seagrass bed in Hong Kong.
But for decades, the Lai Chi Wo river has been getting left behind as its village population dwindles. The river is located in a village of the same name, a valley surrounded by hills on three sides and an estuary on the other. Traditionally, its community relied on subsistence farming, capitalising on the village’s abundant water supply and cultivating growing fields in the catchment areas and terraced fields in the hillsides. But Lai Chi Wo’s luck changed in the 1970s and 1980s as many, mirroring greater demographic trends in Hong Kong, moved to urban areas and abroad, leaving only a few residents behind.
This became problematic for the Lai Chi Wo river. The village’s agricultural production rested upon the river’s management, and keeping the river functioning well was labour-intensive work: previously, farmers were required to actively manage the whole river catchment for irrigation and domestic purposes, villagers actively cleared stream sediments, maintaining stream depth and protecting irrigation structures. With the migration of many villagers, this crucial and labour-intensive desiltation work could no longer continue, reducing the river’s agricultural potential and its capacity to regulate flooding and intense rainstorm events.
