basin

circle

clarification

clean

cleaned

cleaner

clear

detail

drinkable

ecology

ecosystem

effluent

environment

equipment

facility

filtration

flow

fluid

fresh

industrial

industry

last

liquid

metal

modern

plant

pollution

pool

potable

purification

recycle

recycling

reservoir

round

sedimentation

separation

settle

sewage

stage

station

storage

system

tank

technology

treated

treatment

urban

waste

wastewater

water