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Your Questions: Bleach and Septic Tanks


I just built a mountain house which has a septic tank – my first – so I’m not knowledgeable about what to and not to use. I use Clorox Ultimate Care – about ¼ capful. Is this dangerous to break down otherwise needed septic bacteria?


Congrats on the mountain cabin; I’m jealous… We get a lot of questions regarding bleach and septic tank usage. Under normal usage, there should be no worry about using bleach in the washer and having it adversely affect the septic system. At the usage rate (¼ cap), and assuming you are using in washing machine, there will be such a small amount of bleach left at the end of your wash cycle. When it is discharged, it will encounter lots of other material to react with in the pipe and be completely gone long before it reaches your septic tank.

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