英文關鍵字
activities
are
backhoe
boat
bottom
canal
city
cleaning
clear
construction
crane
debris
deepening
digging
dirt
dirty
dredge
dredger
dredging
ecological
ecology
engineering
environment
environmental
equipment
excavation
excavator
excavators
floating
garbage
industrial
industry
lake
landscape
machine
machinery
maintenance
management
mud
nature
outdoors
platform
pollution
purification
recycling
reservoir
river
rivers
scoop
sediment
sewage
ship
sludge
special
takes
treatment
urban
waste
water
waterway
work
working