sewage works vs sewer system

sewage works and sewer system both are nouns.

Word	Noun	Adjective	Verb	Adverb
sewage works	Yes	No	No	No
sewer system	Yes	No	No	No

As nouns, sewage works and sewer system are synonyms defined as:

sewage works and sewer system: facility consisting of a system of sewers for carrying off liquid and solid sewage

Other synonyms of sewage works include sewage system.

sewage works (noun)	sewer system (noun)
facility consisting of a system of sewers for carrying off liquid and solid sewage	facility consisting of a system of sewers for carrying off liquid and solid sewage