Septic Tank Sizing

Minimum tank gallons from bedrooms or daily flow.

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Formula and source

Tank capacity from EPA on-site wastewater treatment manual sizing rules and state minimum-volume tables; required volume = bedrooms × per-bedroom rule + safety reserve.

U.S. EPA Onsite Wastewater Treatment Systems Manual (EPA/625/R-00/008); state-published per-bedroom rules.

Audience

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Posture

Rough Logic answers the math question the working professional asks on the job. The site is a calm, fast, ad-free, account-free, ever-free reference. It does not interpret code. It does not replace the licensed professional. It does not store your inputs. The Authority Having Jurisdiction governs all installations and inspections.