# Global reservoir levels and water management

> Live situation record from CLSTR: https://clstr.news/situations/global-reservoir-levels-and-water-management
> Updated: 2026-09-30T17:52:41.000Z. Sources: 13. Developments: 2.

Water reservoir levels and management strategies continue to show significant regional variation across Europe and Latin America.

In Portugal, the Portuguese Environment Agency (APA) reported dam capacities averaging 77% due to heavy winter rainfall. In Spain, the Duero basin shows mixed results, with some reservoirs in León maintaining levels above the 20-year average while others remain below historical references.

In Brazil, the Greater Curitiba region saw reservoirs reach 100% capacity, prompting the Paraná government to announce a 25% reduction in water and sewage tariffs for approximately 2 million residences. In Chile, the Santa Juana Reservoir has reached 99.2% capacity following winter rains and snowmelt, marking a recovery from previous drought risks.

In Paraguay, the Yacyretá binational entity reported reservoir levels at 82.86 meters above sea level, though recent reports indicate levels are stable but slightly descending. In the Uruguay River, flows are showing an upward trend near Concordia and Salto, with Salto Grande monitoring rising flows and open spillways.

In Mexico, water levels show mixed results. The La Boquilla dam has reached 23.20% capacity, while the Lázaro Cárdenas dam operates at 28.41%. To address shortages at the latter, authorities in Coahuila and local producers have initiated an atmospheric cloud seeding program in the upper Nazas River basin. Additionally, dams in Querétaro remain below 50% capacity, presenting agricultural challenges.

## Claims

- The Yacyretá reservoir level was 82.86 meters above sea level on September 30, 2026. (single source)
- The forecasted daily inflow for the Yacyretá hydroelectric plant is 15,800 m3/s. (single source)
- The La Boquilla dam reached 23.20% of its storage capacity on September 30, 2026. (single source)
- Inflow upstream of the La Boquilla dam is approximately 163 cubic meters per second. (single source)
- The Government of Coahuila and local producers are using atmospheric cloud seeding to increase water levels in the Lázaro Cárdenas dam. (single source)
- The Lázaro Cárdenas dam is operating at 28.41% of its maximum ordinary water level. (single source)

## Timeline

### 2026-09-30: Global water reservoirs report varying levels and flow trends

Global hydrological reports show diverse water trends: Chile's Santa Juana Reservoir nears full capacity, while parts of Mexico and Spain manage varying levels of drought and irrigation needs.

9 sources. https://clstr.news/cluster/regional-reservoir-levels-fluctuate-across-paraguay-and-mexico

### 2026-09-14: Water reservoir levels reach 100% in Curitiba and 77% in Portugal

Water reservoir levels in Portugal average 77% capacity, while reservoirs in Greater Curitiba, Brazil, have reached 100% following heavy rains. Regional updates include water tariff reductions in Paraná.

4 sources. https://clstr.news/cluster/portugal-dams-reach-77-average-water-storage-capacity

---
Cite as: Global reservoir levels and water management. CLSTR, https://clstr.news/situations/global-reservoir-levels-and-water-management