What causes a sewer to back-up?

Most sewer backups happen because the line is plugged with debris. Typical solids that build up in the pipe and cause backups are fats, oil, grease (FOG), dirt, hair, bones, sanitary products, paper towels, kitty litter, diapers, broken dishware, garbage, eggshells, coffee grounds, and concrete. 

Tree roots can also cause backups. Tree roots are attracted to wastewater lines because of the waters' warm temperature and nutrients. Roots can infiltrate the pipe system and clog wastewater flow.

Show All Answers

1. How does my wastewater get into the City of Redmond’s sewer?
2. How close to my lateral sewer pipe can I plant trees?
3. Can I flush wipes (cleaning, facial, or baby wipes) down the toilet even if they're labeled "flushable"?
4. What can I do to prevent sanitary sewer back-ups?
5. What causes a sewer to back-up?
6. Can I plant over manholes or clean outs in my yard?
7. What causes sewer odors in my home?
8. What should I do if I have a sewer back-up?
9. How can I find out if there is a wastewater utility easement on my property and what activities are permitted within that area?
10. I have a grinder or STEP (Septic Tank Effluent Pumping) system. How do these systems work? Is there anything else I should know?
11. How can I tell that I have a problem with my plumbing?
12. Where do the majority of sewer back-ups occur?
13. Will the City "unclog" my lateral sewer pipe?
14. What are those City of Redmond Wastewater trucks doing in my street?
15. Who do I contact if I need work performed on my lateral sewer pipe?
16. How can I determine where my lateral sewer pipe is located?
17. Who do I contact if a back-up in the City’s sewer main has caused damage to my property?