File picture: Bongani Mbatha /African News Agency (ANA)

Cape Town – SANParks has closed two of its popular hiking trails on the Garden Route after the SA Weather Service issued a warning of a predicted 50 to 80mm of rain from 1pm today into the late morning tomorrow.

The areas to be affected by the warning of localised flooding include Mossel Bay, George and Knysna.

As a precautionary measure, SANParks has closed the Half Collared Kingfisher and the Brownhooded trails until after the rain.

The SANParks marine ranger in Wilderness, Jonathan Britton, has confirmed preparation channels are in place at both Swartvlei and the Touw River, two of the Garden Route National Park’s open/close estuaries.   

"This significantly shortens the time required to open a channel through the sandbar. A channel typically takes 8-10 hours to dig. With the preparation work in place, it takes about 30-45 minutes to open the estuary mouth," said Britton.

Residents will also keep a lookout on an excavator in Swartvlei and also in Touw River this afternoon. Driver operators and SANParks rangers will be monitoring water levels throughout. 

Rangers and volunteers will also be watching the four live weather stations closely, which include Buffelskop, Touw River, Corneliskop and Farleigh in the catchment areas. 

Residents can view information about live rainfall data which informs decision-making from www.iweathar.co.za. 

"Tides, swell direction and swell size are also constantly monitored as these are important factors that must also be considered during breaching," said Britton.  

Water levels for Swartvlei are currently at 1.71m and those for Touw River at 1.72m. The method used for the opening and closing of estuary mouths, also known as "periodic artificial breaching", results in an exchange between lake and marine water.

"Breaching of the Swartvlei system occurs when water levels reach 2m above mean sea level and between 2.1 to 2.4m for the Touw River estuary. 

"The real-time rainfall also informs us when it is required to open the mouths before the prescribed breaching heights," said Britton.

Cape Times