The short answer
Common Causes
A sewer odor outside often means raw sewage is seeping into the soil. A cracked or broken sewer pipe under your lawn can release wastewater slowly, and the smell rises through the grass. Tree roots can also invade old clay or concrete pipes, creating gaps where gas escapes.
Another frequent cause is a blocked or frozen vent stack on your roof. Sewer gases need to escape upward; if that vent is clogged, the pressure pushes gas out through the yard. A dry soil stack in an unused bathroom can also let odors travel through the ground.
How to Check Your Yard
Walk around and look for unusually green, soggy, or depressed patches of grass. These can indicate a slow leak. Also check for cracks in your driveway or walkway where gas might rise. Pay attention to the smell near cleanout caps, which are the round plastic or metal lids in your yard that access the sewer line.
If you suspect a leak, do not dig blindly. Call a plumber to run a camera down your sewer line to locate the break. You can also pour a small amount of water down a cleanout to see if the smell changes, but leave the serious inspection to the pros.
- Look for soggy or extra-green grass
- Check for cracks near cleanout caps
- Sniff near the base of your house
- Note if the smell is stronger after rain
- See if the odor is worse in warm weather
When It Is the Septic System
If your home uses a septic tank, the odor could come from a full or failing tank. A damaged tank lid or a clogged drain field can cause sewage to back up and smell. You might also notice slow drains inside the house, which points to a septic issue.
Have a septic professional inspect the tank and drain field. They can measure sludge levels and check for leaks. If the drain field is saturated, you may need to reduce water use and have the system serviced. Do not attempt to open the tank yourself, as the gases can be hazardous.
What the Pros Can Do
Local water damage pros can help after the source is found. They use moisture mapping and leak detection to trace the exact path of water or sewage under your yard. This helps identify whether the problem is a pipe leak or a groundwater issue.
Once the leak is located, the pros can excavate the area, repair or replace the damaged pipe, and dry out the surrounding soil. They also handle cleanup if sewage has contaminated the area. In some cases, they remove water-damaged sod or flooring if the leak reached your foundation.
- Use leak detection to find the source
- Excavate and repair broken pipes
- Dry out soil and remove contaminated material
- Check for water damage to your foundation
- Work with your plumber to fix the root cause
Preventing Future Odors
To avoid repeat smells, keep your sewer lines clear of tree roots and debris. Have a plumber inspect your lines every few years, especially if you have large trees near the pipes. Fix any cracks in your cleanout caps and ensure they are tightly sealed.
Also, keep your vent stacks clear of leaves and nests. If you have a septic system, pump the tank on a regular schedule based on your household size. If you live in Layton, keep a diagram of your sewer line locations handy for future reference.
Talk to someone now
Call (801) 383-0232 any time, day or night, and describe what happened.
Call Now (801) 383-0232Frequently asked questions
Is a sewer smell in the yard dangerous?
It can be. Sewer gas contains methane and hydrogen sulfide, which are harmful in high concentrations. If you feel dizzy or nauseated, leave the area and see a doctor. Open windows and doors to ventilate, and call a plumber to find the leak.
Can I fix a sewer smell myself?
You can check for obvious issues like a loose cleanout cap or a clogged vent, but digging up a pipe is risky. You might damage utility lines. Call a plumber to locate the leak safely. The pros can then handle any water damage cleanup.
Will my insurance cover sewer line repair?
Policies vary, and your insurer decides what is covered. Some policies cover sewer line damage from tree roots or wear, while others exclude it. Contact your insurance company to ask about your specific coverage before starting repairs.