Do I need septic approval for a Travis County addition?
Answered by AskBaily Editorial · Updated
Short answer
If your parcel is NOT served by Austin Water, yes — Travis County On-Site Sewage Facility (OSSF) rules require a licensed designer or registered sanitarian to evaluate drainfield capacity whenever a bedroom addition, fixture-count increase, or fixture-hour change is proposed. Failing OSSF review before DSD permit can block the whole project or force a system replacement mid-build.
In detail
If your parcel is NOT served by Austin Water, yes — Travis County On-Site Sewage Facility (OSSF) rules require a licensed designer or registered sanitarian to evaluate drainfield capacity whenever a bedroom addition, fixture-count increase, or fixture-hour change is proposed. Failing OSSF review before DSD permit can block the whole project or force a system replacement mid-build.
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