The Ignacio Allende Dam release pushes Laja and Lerma rivers higher, triggering evacuation warnings in ten municipalities as heavy rains continue.
Heavy rains in Guanajuato have driven the Ignacio Allende Dam in San Miguel de Allende to 93.6 percent of its ordinary maximum storage. To avoid uncontrolled overflow, authorities began a controlled release this Thursday. The move will raise water levels in the Laja and Lerma rivers, prompting urgent warnings for residents in ten municipalities.
Ignacio Allende Dam release
Civil Protection officials say the controlled release is essential to prevent a sudden, massive spill. “Avoid crossing rivers, even if they appear calm; the flow can increase suddenly,” the State Civil Protection Coordination warned.
As water pours from the reservoir, communities along the Laja River face higher flood risk. The ten municipalities under alert are San Miguel de Allende, Comonfort, Celaya, Villagrán, Cortazar, Salamanca, Pueblo Nuevo, Huanímaro, Abasolo and Pénjamo. Local governments have issued clear instructions to stay away from riverbanks and low-lying crossings.
Forecasts from the National Meteorological Service (SMN) predict 25 to 50 mm of rain per day between July 17 and 19 in the dam’s catchment basin. Continued downpours will keep inflows above 80 m³/s—peaking at 102 m³/s—heightening the risk of flash floods and erosion downstream.
The dam stands at 1,828.36 meters above sea level. Engineers and CONAGUA staff monitor levels around the clock, coordinating with state and municipal bodies to adjust release rates if conditions change.
Municipal warnings and support
The Comonfort municipal government has identified high‑risk zones in San Pablo, Morales, Orduña de Abajo, Colonia Álvaro Obregón and Empalme Escobedo. Officials there urge families in vulnerable areas to prepare evacuation kits and heed official bulletins.
“We ask residents to remain alert to official announcements, not to cross the river under any circumstances, and, if necessary, to evacuate their homes with the support of authorities,” the local administration said.
Emergency services have deployed patrols, rescue boats and mobile command units at critical points. Health and fire departments stand ready to assist with evacuations and emergency shelter operations.
Risk of property loss and flash floods
Civil Protection reminds people living near waterways or in low‑lying neighborhoods to pack vital documents and keep a family evacuation plan ready. A sudden surge in river flow can damage homes, block roads and sweep away vehicles.
In case of emergencies, citizens should dial 911 for immediate aid. Official updates will appear on state government social media, municipal websites and trusted local news outlets.
Key safety recommendations:
- Do not attempt to cross swollen rivers or streams on foot or by vehicle.
- Stay at least 50 meters from riverbanks, dams and embankments.
- Keep important documents and emergency kits within reach.
- Follow bulletins from Civil Protection, CONAGUA and municipal authorities.
- Call 911 for urgent rescue or medical support.
The situation is evolving rapidly. Residents of Guanajuato’s central valley should remain vigilant through the weekend as the Ignacio Allende Dam release and seasonal rains test the region’s flood defenses.
San Miguel de Allende, Ignacio Allende Dam, flood warning, Laja River, Lerma River, Civil Protection, Guanajuato
