英文關鍵字
canal
chemical
contamination
creek
danger
dark
dirty
discharge
drain
drainage
dump
ecology
environment
environmental
exit
factory
flow
flowing
industrial
industry
mud
nature
ocean
old
pipe
pipeline
poison
poisoning
pollution
reflection
river
round
running
sea
sewage
sewer
sewerage
sludge
small
smelly
splash
storm
stream
toxic
treatment
tube
tunnel
underground
unhygienic
waste
wastewater
water