The pyramid shows contamination layers by depth. Red layers indicate critical pollution levels.
Surface (0m)
2m depth
4m depth
6m depth
8m depth
Surface Zone
Surface Zone (0-2m)
High oxygen exchange
Low contaminant accumulation
Mixing Zone
Mixing Zone (2-4m)
Moderate contaminant levels
Natural water circulation
Mid-Column Zone
Mid-Column Zone (4-6m)
Contaminant settling begins
Reduced oxygen levels
Accumulation Zone
Accumulation Zone (6-8m)
Heavy contaminant settling
Low dissolved oxygen
Bottom Zone
Bottom Zone (8m+)
Maximum contaminant accumulation
Anoxic conditions possible