The Municipalidad de Puente Alto (the local municipal government) carried out a preventive evacuation of 172 families from the Valle Hermoso and El Sueño de Todos informal settlements on Tuesday, during the frontal system affecting the Región Metropolitana (the Santiago metropolitan region). Four families have refused to leave, according to Mayor Matías Toledo.
According to BioBioChile, Toledo said public safety teams, emergency crews and Carabineros (Chile's national police) are constantly present at the site. The mayor praised residents' response to the deployment.
The municipality's attention is focused on the La Morfilana and Lo Planella ravines. They were last activated 12 years ago, and the most serious event was three decades ago. The municipality is also monitoring the Hacienda El Peñón area.
"Because there is a historical memory of water events in the area, we prefer to prevent", Toledo explained. He recalled that in past episodes those families were cut off, and that the evacuation was requested on Monday, ahead of the burst of rain that the Servicio Nacional de Prevención y Respuesta ante Desastres (Senapred, the national disaster prevention and response agency) projected for 18:00.
Santiago Governor Claudio Orrego reported in the afternoon that between 10 and 15 millimeters had fallen, against a forecast of 40 for the day. For that reason, he said, there was still "a good while" before the frontal system ended.
Orrego described the evacuations as "absolutely voluntary" and added those at the Ribera del Río settlement in Talagante and Lamparaíso in Lampa. He also reported flooding in Lo Espejo and hail in Maipú, though he clarified that so far there had been nothing that could not be handled with the available equipment.
The governor urged people not to let their guard down. He recalled that last week one hour of rain left two comunas (municipal districts) under water and that there was a mudslide in Las Condes. He asked people to stay informed through official channels.
According to Orrego, the greatest risk lies in the ravines. He acknowledged that Santiago "is not 100% prepared" for these frontal systems and proposed investing more in the Andean foothills and reviewing urban planning. He added that in some comunas the problem is not a lack of protective netting, but its ongoing maintenance and cleaning.
On top of this came damage to road connectivity. The rain caused the asphalt layer to break away on Avenida Concha y Toro, before the San Ramón bridge over the Maipo River, on the boundary between Puente Alto and Pirque, La Tercera reported.
That road is one of the few access routes to Pirque. According to its mayor, Jaime Escudero, up to 4,000 vehicles at rush hour use it. "This was something we had not budgeted for", he said, since the municipality's concern had been the ravines. Almost 20 millimeters fell in Pirque in less than 12 hours, with no ravine activation.
Toledo clarified that it is neither a sinkhole nor structural damage to the bridge. "Buses and trucks go through here, and this road, with a thin little layer of asphalt, can't hold up", he said. "We need a bigger project", he added.
Municipal crews from both comunas were working to reopen the road. Toledo said that up to that point he had not been able to reach the Ministries of Housing and Urban Planning, Transportation, and Public Works, whom he will ask for support. Both mayors asked residents to follow the municipalities' social media accounts for updates on the road's condition and possible alternative routes.
