Water and sewer lines should be inspected annually to ensure they are functioning properly and to catch potential issues early. Regular inspections help identify problems like corrosion, leaks, or root intrusion before they become major concerns. For older homes or properties with large trees, more frequent inspections may be advisable. Additionally, if you notice slow drainage, unpleasant odors, or unexplained water bills, an immediate inspection is recommended. Routine inspections can prevent costly repairs and emergencies.