Which two methods are commonly used for sewer cleaning?

Hydro jetting and mechanical rodding are widely recognized methods for effectively cleaning sewers. Hydro jetting employs high-pressure water jets to dislodge debris, grease, and other blockages within sewer lines. This method is particularly effective for clearing tough build-ups or obstructions, ensuring that the pipes are thoroughly cleaned and maintained.

Mechanical rodding, on the other hand, involves using a flexible rod with a cutting or scraping tool at the end, which is pushed through the sewer line to physically break apart and remove blockages. This method is useful for addressing solid material clogs and can be employed in situations where hydro jetting may not be effective or feasible.

Together, these two techniques complement each other, providing a comprehensive approach to maintaining sewer systems. Other methods mentioned in the incorrect options may not be as effective for the type of debris commonly found in sewer systems or might be applicable in more specialized scenarios, making hydro jetting and mechanical rodding the preferred choices for routine sewer cleaning tasks.