This is the 12356th most frequent Russian word.
канализационных
"Relating to sewage or drainage systems."
Here, 'канализационных' is an adjective describing 'труб', referring to pipes related to sewage systems.
В городе построили новые системы канализационных труб.
In the city, new systems of sewer pipes were built.
In this example, 'канализационных' modifies 'служб', indicating services pertaining to sewage management.
Работа канализационных служб важна для поддержания чистоты.
The work of the sewage services is important for maintaining cleanliness.
Here, 'канализационных' is an adjective modifying 'стоков', referring to effluents associated with sewage.