英文關鍵字
background
base
canal
city
dirty
down
drain
drainage
drains
ecosystem
factory
flood
flow
flowing
grease
industrial
industry
into
manufacturing
nature
pipe
pit
pond
pool
process
rain
road
scale
sewage
sewer
storm
stormwater
street
stripper
swirl
the
trap
treatment
turbid
turbidity
urban
vortex
waste
water
wet