CapeNature artificially opened the Bot Estuary mouth in accordance with the approved Estuary Management Plan and Mouth Maintenance Management Plan, which provide for artificial opening when specific environmental triggers and conditions are met.

A Breaching Committee meeting was held the previous week to assess the prevailing conditions. While the A Breaching Committee meeting was held the previous week to assess the prevailing conditions.

While the water level was approximately 2.4, just below the 2.5 trigger, other factors also needed to be considered. Salinity was around 9, below the 10 threshold, which increased the risk of fish mortality should further freshwater enter the system without an opportunity for exchange with the marine environment.

The Klein Estuary at Grotto Beach, Hermanus, was also open, and the need for marine species to move between the Klein and Bot estuaries was another factor in the decision to open the Bot Estuary.

CapeNature’s Pierre de Villiers, Senior Manager for Marine and Coasts Operations, explained that the need to restore connectivity between the estuary and the sea, allowing the movement of fish and other aquatic species, was also considered.

He said the favourable weather window during last week provided suitable conditions to undertake the opening.

He said the berm will be breached at its lowest point, opposite the historic channel. The last artificial opening took place in 2025, when the levels and triggers were also reached, after which the mouth subsequently closed naturally as water levels declined. The Klein Estuary also closed but opened naturally this year, while the Bot requires an artificial opening.

The estuarine system itself has also been influenced by historical human intervention and changes to waterways connecting the estuary and the marine environment.

The decision is guided by the approved management framework. The Estuary Management Plan is approved by the Western Cape Provincial Minister of Local Government, Environmental Affairs and Development Planning, MEC Anton Bredell, and reviewed every five years, while the Mouth Maintenance Management Plan is approved by DFFE (Department of Forestry, Fisheries and the Environment) and is also reviewed every five years.

The current plan runs until 2027. Comments and proposed changes received during the public comment period will be considered as part of the next review. Environmental conditions and the ecological functioning of the estuarine system are also taken into consideration.

CapeNature, Overstrand Municipality Environmental Management and Conservation, members of Law Enforcement, and the municipal operational team assisting with machinery were on the ground during Friday’s operation. Operations continued into the night. The necessary monitoring for illegal activity also took place over the weekend.