Agrio River Pollution 2026: 2,389 ha without irrigation and emergency solution for Guadiamar irrigators

Key data

Thousands of hectares of crops in Seville province were left without irrigation water in the middle of the growing season. The cause: effluents with heavy metals from the Aznalcóllar mine which, following February 2026 rains, contaminated the Agrio River counterreservoir and rendered the usual supply to the Guadiamar system unusable. The Resolution of September 29, 2026 from the Guadalquivir River Basin Authority publishes the emergency agreement that activates an alternative solution.

The institutional response is based on Law 40/2015 and water legislation, expressly recognizing the situation as an unforeseen water emergency with serious economic consequences for farmers in the area.

What does this regulation establish?

The agreement signed between the CHG and the Isla Mínima Canal Irrigation Community establishes the provision to the Authority of private irrigation infrastructure to respond to the emergency. The transferred infrastructure includes:

• Casa Rieras Canal: irrigation canal owned by the Isla Mínima Canal Irrigation Community.
• Los Patos pumping station: pumping facility also belonging to said community.

To make this alternative solution operational, the agreement contemplates the execution of the following works:

• Cleaning of the Casa Rieras canal.
• Installation of gates.
• Construction of an intake structure to divert water from the Guadalquivir River.

The objective is to divert up to 2 m³/s from the Guadalquivir through these infrastructure, replacing the supply that usually came from the Agrio River counterreservoir, now contaminated.

The agreement is based on the Law 40/2015, on the Legal Regime of the Public Sector, and on sectoral water legislation, configured as an emergency response to an unforeseen situation that did not allow for ordinary procurement timelines.

Economic and operational impact

The contamination of the Agrio River counterreservoir is not a minor technical problem: it directly affects the economic viability of agricultural operations in the Guadiamar system during the 2026 growing season. Without irrigation water, crops—among which rice stands out—cannot complete their productive cycle.

The agreement allows recovery of supply on 1,693 of the 2,389 affected ha, which represents approximately 71% of the blocked area. The remaining 696 ha are outside the scope of the emergency solution activated.

The operational consequences for farmers and irrigation communities include:

• Need to adapt irrigation schedules to the new alternative supply system.
• Possible flow restrictions compared to usual supply, given that the maximum derivable is 2 m³/s.
• Mandatory coordination with the CHG and with the Isla Mínima Canal Irrigation Community for the use of transferred infrastructure.
• Uncertainty about the recovery timeline of the Agrio River counterreservoir and return to ordinary conditions.

For operations that fall outside the 1,693 recoverable ha, crop loss can be total if other complementary measures are not implemented.

Who does it affect?

• Irrigation communities of the Guadiamar system (Seville): are the main parties affected by the supply cutoff.
• Doñana Irrigation Community: expressly cited as a beneficiary of the emergency solution.
• Isla Mínima Canal Irrigation Community: transfers its infrastructure (Casa Rieras Canal and Los Patos pumping station) to the CHG to implement the solution.
• Rice farmers and other crop growers on the 2,389 ha of the affected Guadiamar system.
• Guadalquivir River Basin Authority (CHG): body responsible for managing the agreement and adaptation works.

Practical example

A 50 ha rice operation integrated into an irrigation community of the Guadiamar system lost its access to irrigation water in February 2026 due to contamination of the Agrio River counterreservoir. Without supply, rice cultivation—which requires continuous flooding in certain phases—cannot be completed.

Thanks to the emergency agreement, if its plot is within the 1,693 recoverable ha, it will be able to receive water diverted from the Guadalquivir through the Casa Rieras Canal and the Los Patos pumping station. To do so, it must coordinate with its irrigation community and the CHG to learn about the supply schedule available under the new scheme, which has a maximum limit of 2 m³/s for the entire benefited area.

If its plot is part of the approximately 696 ha that fall outside the scope of the emergency solution, crop loss can be total in the 2026 growing season, making it urgent to contact the CHG to explore complementary measures or access possible compensation mechanisms.

What should irrigation communities do now?

1. Verify if your area is within the 1,693 recoverable ha. Contact the CHG or the board of directors of your irrigation community to confirm which plots fall within the area benefited by the emergency agreement.
2. Coordinate the irrigation schedule with the CHG. The alternative supply has a limit of 2 m³/s, so it may be necessary to establish shifts or flow restrictions among the benefited communities.
3. Document damages incurred since February 2026. Precisely record crop losses and additional costs incurred, in view of possible claims or access to compensatory aid.
4. Consult with the CHG about recovery prospects for the Agrio River counterreservoir. The emergency solution is temporary; it is advisable to know the timeline for return to ordinary conditions to plan future growing seasons.
5. If your plot falls outside the 1,693 recoverable ha, explore compensation avenues. Contact the CHG, the Junta de Andalucía, and agricultural organizations to identify possible aid mechanisms for operations that cannot be served by the agreement.

Official source

View complete regulation at official source

Notice: This article is for informational purposes only and does not constitute legal advice. For specific decisions, consult a qualified professional. Source: https://www.boe.es/diario_boe/txt.php?id=BOE-A-2026-20810