Huallalolén, Seca and Ñilhue ravines

End of January 2021, the metropolitan area of Santiago endured heavy rainfalls of more than 116 mm. A phenomenon that had not occurred since 1933. This, plus the scarce vegetation in the mountains and a zero isotherm above 3,500 meters, activated several streams and gullies.

In the commune of Lo Barnechea the water affected homes, streets, roads, and infrastructure and caused emergency works.

The solution consists of seven dynamic barriers of the VX-type installed in the three streams affected mainly by the floods.

• Seca gully: 1 VX-80-H4 barrier 16 meters wide and 4 meters high
• Ñilhue gully: 1 VX-160-H6 barrier 13 meters wide and 6 meters high and 2 VX-140-H4 barriers 12 meters wide and 4 meters high
• Huallalolén gully: 3 VX-140-H4 barriers 18 meters wide and 4 meters high

The retention capacity of all seven ring net barriers is 6’900 m³.