An illegal, private dam is being blamed for flooding in Valle del Bravo, México state, on September 3.

Located in the community of Álamos, the dam overflowed due to a structural weakness, reported the newspaper Milenio. Millions of liters of water spilled out of the dam, flooding fields and properties in the vicinity of the El Molino River, where the water rose six meters.

Environmental organizations in Valle del Bravo made formal complaints about the dam on August 17, more than two weeks earlier. It was closed on September 13 by the federal environmental protection agency, Profepa, which said the dam was closed because it wasn’t authorized.

“… the construction of an artificial lake on an approximate area of 8,000 square meters, for which the authorization for environmental impact was not presented … affected a forest area of approximately 7,500 square meters due to flooding …”

Local resident Morgan Szymanski said the environmental impact was severe. “We estimate that the water level rose approximately five to six meters. The natural impact is terrible, the flora and fauna that disappeared in the space of two hours. It’s a great shame and all the neighbors are very angry,” he said.

Lorenza García, whose property was damaged by the flood, emphasized its scale. “What happened here can be called a tsunami,” she said.

She added that authorities had been too slow to act. “The authorities need to take responsibility for not stopping this in time. We made a public complaint, long before that dam burst, and nobody did anything. All this could have been avoided,” she said.

Milenio reported that the the construction of private dams increased during the COVID-19 pandemic, and claims there are dozens of unauthorized dams in the area.

A civic group in Valle de Bravo said the illegal dams are likely to cause environmental damage and are a threat to the local population. “The construction of private dams in Valle del Bravo, without having the corresponding environmental impact permits, cannot go unpunished. The environmental and material effects that these projects can cause are immeasurable, not to mention the risk to human life.”

With reports from Milenio