Does the smell come from the shower, sink, toilet, or laundry? Write it down. If it is only one drain, the trap below that drain is likely the issue. If it is all drains, the main line is the problem.
If it is the toilet, flush it a few times. If it is a sink, run water for 30 seconds. This refills the trap with water, which blocks sewer gas from rising up. The smell should improve immediately if the trap is the culprit.
Look for a white PVC pipe sticking up near the center or edge of the roof. That is the main vent pipe. If you can see it from the ground, it is open and clear. If you see dirt, leaves, or debris at the opening, the vent is clogged.
If refilling the trap or clearing debris does not help, or if the smell comes from multiple drains at once, a plumber needs to run a camera down the main line to see if there is a clog, a break, or tree roots invading the sewer pipe.
Sewer smell in your home is never normal and never something to ignore. It comes from decomposing waste and bacterial gas that should stay inside the pipes and exit through the roof vent. When smell reaches your nose indoors, the seal or vent system has failed somewhere. In Prunedale, where many homes have older drain systems and are surrounded by trees and vegetation, tree roots are a common culprit. Roots seek out moisture and can crack or clog sewer lines over years.
The most common cause is a simple one: the trap under a sink, shower, or toilet has dried out. Every drain has a U-shaped section filled with water that acts as a seal. If a drain has not been used for weeks, the water evaporates and gas rises up from the sewer. Running water down it again usually fixes the smell in minutes. If that does not work, the problem is deeper.
A blocked vent pipe on the roof keeps sewer gas from escaping upward, so it backs up and comes out through drains instead. This is also fixable, but you need a plumber to safely climb the roof and clear it. If multiple drains smell at once, the main sewer line has a clog or a break. A camera inspection is the only way to know for certain. The longer you wait, the more gas accumulates and the worse the smell gets.
Describe what you're seeing to a real Prunedale plumber: call (831) 555-0170 or send the form. Free, no obligation.