Residents of São Marcos remain on alert due to the risk of the Arroio São Luiz Dam breaking

Residents of São Marcos, in Serra Gaúcha, remain on alert for the risk of the Arroio São Luiz Dam breaking. On the afternoon of this Wednesday (23), the Civil Defense of Rio Grande do Sul issued a severe warning of very high danger for the imminent collapse. The notice is aimed at properties close to the structure and on the banks of the Jaguari River.

A Civil Defense Cell Broadcast alert was sent to the region at 3:53 pm, advising the population to prepare for an evacuation. According to Corsan Aegea, around 170 residents were removed from their homes and are staying in family homes and hotels.

"There is a risk of collapse of this structure and yes, there was a risk and there is a risk to the lives of people in these places", says Marcelo Almeida de Souza, Civil Defense coordinator.

According to him, the law determines that an action plan must be planned for an extension of up to 10 kilometers from the dam outlet.

The consequences of the risk of rupture also changed the municipality’s routine. Classes at a school located in the risk area were suspended and a road had to be closed.

The company states that dam safety experts are in São Marcos carrying out a "detailed assessment of the Arroio São Luiz Dam, after the activation of the Emergency Action Plan (PAE) this Wednesday (23)".

The technical diagnosis must be completed by Friday (25) and will define the necessary maintenance and contingency measures in the structure.

To try to prevent collapse, pumps were installed with the aim of increasing the flow and lowering the reservoir level more quickly. A crisis cabinet meeting this Thursday morning should update information to assess whether the security level can be reduced.

"Pumps are being installed to accelerate the reduction of the reservoir's water level and reduce the pressure exerted on the dam", highlights Corsan.

In the early afternoon of Wednesday, the estimated volume of the reservoir was approximately 138 thousand cubic meters. By 10:17 p.m., it had been reduced to around 135,000 cubic meters. With the pumps in operation, the water removal capacity must be accelerated.

The alert was issued due to the high volume of rain recorded this week. In just 24 hours, it rained more than expected for the entire month of September in the municipality. There were 174 millimeters of rain in one day, compared to a historical average of 163 mm, according to Climatempo Meteorologia.

"After the rains, we intensified inspections of the structures, identified cracks in the dam and, in compliance with the Action and Emergency Plan, we activated all responsible areas, effectively considering ensuring the safety of people located below the dam", says Corsan Aegea Operations Director, Maraisa Mendonça.

Note from the State Civil Defense: "On the afternoon of this Wednesday (23), the State Civil Defense was informed by Corsan about a possible rupture of the Arroio São Luiz dam, located in the municipality of São Marcos, after identifying damage to the dam structure. The preventive evacuation of around 60 buildings in potentially affected areas has already begun, including a school. Civil Defense RS, through the 9th Regional Coordination, is monitoring the situation on site, providing support to the municipal teams, Corsan and other response forces. A Cell Broadcast alert was sent to the region at 3:53 pm, advising the population to prepare for an evacuation. Corsan's technical teams identified leaking cracks in parts of the dam's structure this Wednesday. Disasters (GIGED) installed a Local Incident Office in the municipality."

Note from Corsan: "Dam safety experts hired by Corsan are in São Marcos carrying out a detailed assessment of the Arroio São Luiz Dam, after the Emergency Action Plan (PAE) was activated this Wednesday (23). The technical diagnosis is expected to be completed by Friday and will define the necessary maintenance and contingency measures in the structure. At the same time, pumps are being installed to accelerate the reduction of the reservoir's water level and reduce the pressure exerted on the dam. dam Corsan works together with the Civil Defense and the City Hall. As a preventive measure, around 170 residents of the risk area were removed from their homes and are accommodated in family homes and hotels in São Marcos and the region, with accommodation paid for by the Company. At this time, it is not yet possible to establish a date for the release of the area. The PAE was activated immediately after the identification of cracks in the spillway and in parts of the dam's buttress. The change was detected during intensified monitoring due to the high volume of rain recorded in the region in recent days, which caused an increase in the water level in the reservoir."