Can you flush laundry detergent with a septic tank?
The short answer for laundry detergent and a septic tank: limit. Powdered detergents can contain fillers that add to the solids in the tank, and doing many loads at once floods the tank with more water than it can settle.
A surge of wash water can push un-settled solids out to the drain field; filler-heavy powders add to the sludge layer. Choose liquid HE detergents, use the recommended amount, and spread laundry across the week instead of one big wash day.
- Verdict
- Limit — liquid HE detergents beat powders; spread loads across the week
- Why
- Powdered detergents can contain fillers that add to the solids in the tank, and doing many loads at once floods the tank with more water than it can settle.
- What it does to your system
- A surge of wash water can push un-settled solids out to the drain field; filler-heavy powders add to the sludge layer.
- Choose liquid HE detergents, use the recommended amount, and spread laundry across the week instead of one big wash day.
When in doubt, throw it out — only the three Ps (pee, poo, toilet paper) belong in a septic system.
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