Sewer odours inside can show a dry trap, cracked air vent

https://alexiskzkb827.lucialpiazzale.com/exactly-how-a-geelong-pipes-company-tackles-blocked-drains-pipes-and-hard-to-find-leaks

Sewer odours inside can suggest a dry trap, broken vent, or partial blockage; Geelong residential properties with huge trees or older sewage system lines may need CCTV evaluations to find intrusions and stop recurring smells.