英文關鍵字
background
canal
chemical
concept
concrete
danger
dirty
discharge
discharging
drain
drainage
dump
ecology
environment
environmental
flood
flowing
flows
garbage
industrial
industry
lake
liquid
natural
nature
pipe
pipeline
plant
polluting
pour
pouring
pump
recycling
reservoir
river
sewage
sewer
sludge
spill
spills
storage
stream
system
toxic
treatment
tube
waste
wastewater
water