Septic tank
What rules must a septic tank in Portugal meet?
Short answer
A fully sealed tank that gets emptied needs no APA licence. If waste water soaks into the ground, through a soakaway or a pit without a sealed bottom, that is a discharge and needs an APA declaration (up to 10 residents) or licence. If there is a sewer in the street, you must connect and take the old pit out of use.
Sealed tank or soakaway
- Sealed tank, emptied by a contractor or the municipality: no APA licence needed. Keep proof of every emptying.
- Septic tank with a soakaway, where pre-treated water goes into the ground: an APA declaration up to 10 residents, a licence above that. Everything except the infiltration part must be watertight.
- Brick pit without a sealed bottom, with no tank before it: does not meet that requirement. Many old houses and ruins still have one.
Sewer in the street
If your house is within reach of the public sewer, a septic tank is no longer allowed. In Tavira the old pit must be taken out of use within 30 days of connecting. For a new build or renovation, the waste water solution is part of the project at the câmara.
Emptying
Never dump sludge in nature yourself. The municipality or water company empties on request; in Loulé through the municipal portal. Infraquinta charges €31.51 per 6 m³ plus VAT in 2026.
Read next
Sources: APA over beerputten met infiltratie (declaration and licence), AC Arquitetos, 2026 (sealed tank), reglement Taviraverde (art. 19 and 29), Aviso 34/2026, Infraquinta (emptying rate), Câmara de Loulé (emptying request).
Last checked: September 25, 2026