"Strong sewage" is a term used to describe highly concentrated and odorous wastewater. It is essential to find appropriate synonyms for this term to avoid repetition in writing and to sound more professional. Some synonyms to use instead of "strong sewage" include noxious waste, foul effluent, pungent wastewater, putrid sewage, malodorous byproduct, and foul-smelling sludge. It is also a good practice to use specific terms depending on the context of the sentence. For example, if talking about sewage containing mostly urine, using the term "strong urine effluent" may be more suitable. Ultimately, finding appropriate synonyms for "strong sewage" will help to make your writing more descriptive and engaging.