When do Houston projects need septic (OSSF) approval?
Answered by AskBaily Editorial · Updated
Short answer
Parcels outside Houston's sewer service territory — typically in unincorporated Harris County, Fort Bend County edges, Montgomery County, Brazoria, or Galveston County — fall under Texas Commission on Environmental Quality OSSF rules, enforced locally. A bedroom addition, fixture-count increase, or footprint expansion on a septic-served parcel triggers a licensed designer's OSSF evaluation before a construction permit issues. A failed soil test can force a $15K-$35K aerobic upgrade.
In detail
Parcels outside Houston's sewer service territory — typically in unincorporated Harris County, Fort Bend County edges, Montgomery County, Brazoria, or Galveston County — fall under Texas Commission on Environmental Quality OSSF rules, enforced locally. A bedroom addition, fixture-count increase, or footprint expansion on a septic-served parcel triggers a licensed designer's OSSF evaluation before a construction permit issues. A failed soil test can force a $15K-$35K aerobic upgrade.
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