Albufeira Convention Protocol II Tightens the Pomarão Guadiana Flow Regime With Spain — Cabinet Sends the Cross-Border Water-Sharing Pact to Parliament for Ratification

The Portuguese Conselho de Ministros (Council of Ministers) on 18 June 2026 approved a Resolution submitting to Parliament the Segundo Protocolo de Revisão da Convenção de Albufeira (Second Revision Protocol of the Albufeira Convention) — the bilateral treaty that has governed water cooperation between Portugal and Spain since November 1998. The protocol's headline addition is a binding flow-regime annex covering the Pomarão hydrometric station in Mértola, the easternmost Portuguese gauge on the Rio Guadiana (Guadiana River) before its course curves into the Algarve estuary at Vila Real de Santo António.

The original convention obliges Spain to deliver agreed annual and weekly water volumes at four control points: Miranda do Douro on the Douro, Cedillo on the Tejo, the Fratel reservoir on the Tejo, and the Pomarão station on the Guadiana. Until now the Guadiana annex set only annual volume targets. Protocol II adds a quarterly and monthly distribution schedule plus drought-trigger pricing for water-conservation derogations, closing the gap that left Portugal exposed when Spain ran upstream reservoirs below conservation pool levels in the late summer of 2023 and again in 2024.

The timing is not abstract

The Comissão para a Aplicação e Desenvolvimento da Convenção de Albufeira (CADC, the joint Portuguese-Spanish secretariat that monitors compliance) recorded five days between October 2025 and June 2026 when no inflow at all reached the Fratel control point on the Tejo. The Guadiana basin has tracked the same trajectory — APA (Agência Portuguesa do Ambiente, Portuguese Environment Agency) modelling pegs mean annual inflow at the Pomarão gauge roughly 12% below the 1990-2020 reference baseline. With the IPMA placing seven southern districts under aviso amarelo (yellow heat-wave warning) for 21-22 June and 23 inland concelhos (municipalities) entering perigo máximo de incêndio (maximum wildfire risk), reservoir operators on both sides of the border are entering a high-stress operating window with the new contractual floor still in draft.

What the Algarve irrigators get

For the agricultural rights downstream of Pomarão, the new monthly schedule is the substantive change. The Algarve regional water plan filed by APA in 2025 estimated a €428 million productivity gap across Mértola, Castro Marim and Alcoutim if Guadiana inflows dipped below a 0.85 m³/s threshold for more than 90 consecutive days. Protocol II raises that contractual floor and binds Spain to weekly readings rather than the annual settlement window that operators on both sides previously used to net out shortfalls. The Pomarão regime also obliges the Spanish hydrographical authority to publish forecast-versus-actual inflow data inside seven working days — a transparency layer that did not exist under the original 1998 text.

What this means for residents and expats

• Algarve water tariffs: Águas do Algarve has signalled it will hold the 2026 summer tariff schedule unchanged while Protocol II awaits ratification, but any renegotiation of agricultural extraction rights below Pomarão could feed into the 2027 review.
• Property near the Guadiana: The lower Guadiana banks between Mértola and Alcoutim sit inside the Reserva Natural do Sapal — environmental due diligence on any riparian property purchase should now include the demarcation map that will accompany the protocol's parliamentary annex.
• Parliamentary calendar: The Assembleia da República (Assembly of the Republic) is expected to schedule the ratification vote before the August recess. A simple majority suffices, but after the Trabalho XXI defeat earlier on 18 June the AD coalition will need PS or IL votes — PS environment spokesperson Hugo Costa has signalled a green-vote in principle.

The protocol does not solve Portugal's structural water-stress arithmetic in the Iberian south — what it does is replace an annual reconciliation regime with a monthly contractual one, which is the difference between catching a shortfall in March and discovering it in October. With Albufeira (the city) under its own summer nightlife cap and the Algarve coastline running a different climate-stress profile from the Mértola interior, the Pomarão floor matters more this year than at any point since the convention entered force in 2000.