The Department of Water and Sanitation (DWS) has given the City of Cape Town permission to construct an emergency spillway on the fourth and remaining farm dam reported to be on the verge of collapse to lower the risk of its collapse.
This follows the failure of three farm dams, located in Riverlands, that breached, resulting in flooding that caused severe property and infrastructure damage to the affected area, leading to hundreds of people being provided with humanitarian assistance.
The department’s Head of Communication, Dr Mandla Mathebula, said the three failed dams did not have sufficient spillways and had filled beyond the safe level, resulting in overtopping due to high rainfall and associated run off, causing them to fail in series.
“The fourth dam, which is the highest dam in the valley, also has no spillway and it has been discovered that it has some structural damage. The dams are owned by the Western Cape Provincial Government and serve local farmers.
“To reduce the risk of potential failure, the DWS Dam Safey Office has granted permission for the construction of an emergency spillway on the fourth dam,” Mathebula said.
Mathebula said construction has started under the supervision of an approved professional person and will ensure that the dam is able to manage the anticipated floods due to the predicted rainfall, which will last until Tuesday.
“The existing outlet pipe of the dam will also be kept fully open to allow the dam levels to drop to safe capacity or even empty if required,” Mathebula said.
According to the preliminary report by the department’s engineers who are on site, the dams failed last week Wednesday at approximately 3am. The town of Riverlands, approximately two kilometres downstream, was partially flooded.
Due to the dams storing the bulk of the catchment runoff and not having any spillways to discharge any water in rainy seasons, the river dried up downstream.
Mathebula noted that most of the affected houses, including the railway line, subsistence farming smallholdings, schools, roads, and other structures, were constructed in the original river flood zones.
He said the department will conduct an investigation into the causes of the dam failures and depending on the results of the investigation, DWS may implement regulatory actions to ensure accountability.
“DWS is doing its best to assist the City of Cape Town during this difficult period to ensure that the situation is normalised. The DWS has dispatched its engineers from the Western Cape Regional Office to provide expert advice to stabilise and rehabilitate the situation.
“A local Joint Operations Committee has been established, represented by a variety of municipalities, disaster management teams, DWS, Gift for Givers, SPCA (Society for the Prevention of Cruelty to Animals), social and humanitarian organisations, amongst others,’” Mathebula said.
The department has assured the communities around the affected area that all hands are on deck to resolve the problem. It encouraged community members to cooperate during this period to ensure speedy work on site.
