The Supreme Court annuls the irrigation areas of the hydrological plans

The Third Chamber (Fifth Section) of the Supreme Court has partially upheld the contentious-administrative appeal 425/2023 filed by the Irrigators’ Community of Campo de Cartagena against Royal Decree 35/2023, of January 24, which approved the revision of the hydrological plans for twelve districts. The judgment, issued on September 17, 2026, declares null the reference to the irrigation areas of each of the irrigable zones in article 13.13.ºd) of the Segura plan and its summary in the annex and attachment 03. The ruling is published in the Official State Gazette (Boletín Oficial del Estado) no. 257, of October 16, 2026, with reference BOE-A-2026-21528.

Royal Decree 35/2023 approved the revision of the hydrological plans for the districts of Western Cantabrian, Guadalquivir, Ceuta, Melilla, Segura, and Júcar, and the Spanish part of the Eastern Cantabrian, Miño-Sil, Duero, Tajo, Guadiana, and Ebro districts, and was published in the Official State Gazette no. 35, of February 10, 2023 (BOE-A-2023-3511). The plans must be revised every six years in accordance with the eleventh additional provision of the consolidated text of the Water Law, approved by Royal Legislative Decree 1/2001, of July 20, and following Directive 2000/60/EC; the revision now questioned corresponds to the 2022-2027 cycle.

This is not the first time the Supreme Court has ruled on this same royal decree. The judgment of July 4, 2025 (BOE-A-2025-15242) partially upheld the appeal of the European Pistachio Council Association and annulled the irrigation allocations for almond, pistachio, and walnut trees in the Tajo and Guadiana. The judgment of April 29, 2026 (BOE-A-2026-11702) upheld the appeal of the Central Syndicate of Irrigators of the Tajo-Segura Transfer and annulled, already at that time, the same reference to the irrigation areas of the Segura plan.

What the ruling declares

The operative part of the judgment of September 17, 2026, agrees:

• To partially uphold the contentious-administrative appeal no. 425/2023 against Royal Decree 35/2023.
• To declare null the reference to the irrigation areas of each of the irrigable zones of article 13.13.ºd) PHS and the summary of the annex and attachment 03.
• To impose costs under the terms indicated in the final legal ground of the resolution.
• To order the publication of the ruling in the Official State Gazette.

The resolution is notified to the parties with the warning that no further appeal may be filed against it and is inserted into the legislative collection.

Who is litigating and who resolves

The appeal was filed by the court representative Mariano Montiel Molina in the name and representation of the Irrigators’ Community of Campo de Cartagena, under the legal direction of Isabel Caro-Patón Carmona. The judgment is signed by the Fifth Section of the Third Chamber, with the following magistrates:

• Carlos Lesmes Serrano, president.
• Wenceslao Francisco Olea Godoy.
• Fernando Román García.
• María Consuelo Uris Lloret.
• María Concepción García Vicario.
• Francisco Javier Pueyo Calleja.

Basins and affected users

The ruling is projected onto the hydrological plan of the Segura demarcation, the basin with the greatest weight in irrigation in the southeastern peninsula and where the recurring community operates. The revised royal decree also covers the following demarcations:

• Western Cantabrian, Guadalquivir, Ceuta, Melilla, Segura, and Júcar.
• The Spanish part of the Eastern Cantabrian, Miño-Sil, Duero, Tajo, Guadiana, and Ebro demarcations.

The annulment affects the summary of irrigation areas of the irrigable zones, a piece of data that conditions allocations, supply guarantees, and the planning of irrigation in these basins.

Impact

The sentence consolidates a jurisprudential line that has already cut the content of Royal Decree 35/2023 regarding irrigation twice: first, the allocations for woody crops in the Tajo and Guadiana, and now the reference to the irrigation areas of the Segura. For the irrigators of the Campo de Cartagena and the Mediterranean arc as a whole, the ruling leaves a key piece of hydrological planning data without regulatory coverage, which forces the basin administrations to redo that part of the plans and opens the door to new litigation over allocations and irrigation guarantees in the 2022-2027 cycle.

Source: Official State Gazette, no. 257, of October 16, 2026, Sec. I. General Provisions, page 138436 (official reference: BOE-A-2026-21528).