● loss of virtually all indigenous riparian vegetation
● encroachment of alien vegetation into the river margins
● nutrient-enrichment, and elevated concentrations of faecal coliform bacteria (CCA Environmental, 1999a; Day and Ractliffe, 2002; Day et al., 2005).
Moreover, dense growth of the invasive bulrush Typha capensis in places along the channel constituted both a safety hazard (the channel was hard to climb out of) and a security threat (reedbeds in this area often harbour criminal elements and facilitate attacks on passers-by).