Thanks to a generous rainy season, Mexico’s most important dams are at a combined 48% of capacity.

According to the National Water Commission’s Technical Operations Committee, 80 of the nation’s top 210 dams were at less than 50% capacity, 27 were at 100% capacity, 44 others were at 75% or above and 59 were found to be between 50-75% full as of July 14.

The Cutzamala System — the large-scale water transfer system that supplies greater Mexico City — held 457.8 million cubic meters of water as of July 21, or 58.5% of capacity, up from 56.4% a week earlier.

Total volume at the Cutzamala’s top reservoirs — Valle de Bravo, El Bosque and Villa Victoria — has doubled since last summer, when an extended drought prompted media reports about a potential Day Zero in Mexico City.

Lake Chapala, the primary source of water for the Guadalajara Metropolitan Area, saw its surface level rise 30 centimeters through the first week of July and is currently at 54.63% of its capacity — a 14.6 percentage-point improvement over July 21, 2024.

Despite this week’s positive data, the committee cautioned that current water volumes are still 2.19 billion cubic meters below the historic average for July of 62.04 billion cubic meters. That’s a deficit of 4%.

Rainy season replenishes Guanajuato’s water supply

Another top beneficiary of the wet summer is the state of Guanajuato, where volume at its eight biggest dams nearly doubled since July 2024, reaching 71.6% capacity as of July 18.

According to state water agency officials, total volume at these eight reservoirs was at 1.261 billion cubic meters, up from 1.207 billion one week earlier. In 2024, their volume barely surpassed 700 million cubic meters, or approximately 29% of capacity. 

Four of the eight dams were operating at 100% capacity: three in Guanajuato city — La Mata, La Soledad and La Esperanza — and the El Palote in León. 

Another three — the Allende Dam in San Miguel de Allende, La Golondrina in Pénjamo and the El Realito in San Luis de La Paz — were above 80%.

However, the much-needed precipitation has not come without its problems. 

Guanajuato struggled with flooding after record rainfall in May, while Mexico City experienced severe flooding in early June.

With reports from La Jornada, Milenio and Zona Franca