MOVEMENT PATTERNS OF RIVERINE LITTER

Aspects of litter movement were looked at in a variety of ways. River bank clearances provided valuable information on litter accumulation a nd movement, showing a distinctive correlation between flood events an d litter movement. Introduction of litter outside of channel depositio n (diffuse sources) were limited in the study area in South Wales, UK. A rise in litter deposition occurred for some time after flood events , with the main accumulation occurring in the mid-bank zone. As only s ome litter types have an increased input during flood events e.g. sewa ge-derived material from combined sewer outfalls (CSO), accumulation o f other litter types, e.g. plastic sheeting could be due to their dist ribution throughout the catchment. A positive correlation between litt er stranding and vegetation was found. During high flows, (75.59 cumec s) litter is removed from sites with little restraining vegetation and deposited where stranding potential is high. Smaller items such as fe minine hygiene products were more susceptible to stranding than larger plastic sheeting.