New evidence of the historic challenges to shipping on the southwest rim of Algoa Bay have emerged during a fascinating new municipal project assessment.
Marine archaeologist Vanessa Maitland, 49, has discovered material from at least two wrecks from the 1800s in a narrow site – just 100m long and 1.5km deep – at Cape Recife.
She said on Wednesday that the debris was lying just 5-7m down on a rocky sea floor.
“There’s tons of stuff. Some of it’s so encrusted with sand and shell concretions and overgrown by soft corals, sponges and seaweed, it looks like part of a reef.
“Some of it’s rolling around on the seabed.”
Her discovery came during an environmental and heritage impact assessment triggered by the future possible upgrade of the Cape Recife Waste Water Treatment Works, planned by the municipality.
Municipal engineer Matthew Hills said that if the upgrade went ahead it might include the need for a new outlet pipe to replace the present one that entered the sea on the east side of the cape opposite the treatment works.
Although the new pipe would be in the same area, the municipality wanted to avoid damaging the area’s environmental and cultural heritage and so the aim was to choose the best alignment, he said.
While it was known that a number of ships had foundered at Cape Recife, precise data needed to obtained.
Maitland and her brother Anthony, who works for her company Cape Town-based Kraken, plus local diver Chris Hookins started by deploying a magnetometer over the site.
Towed behind their boat, the device picked up the slightest variations in the Earth’s magnetic field, she said.
These were produced by various anomalies – including the presence of iron, which was introduced to ship building from the early 1800s.
“Data from the magnetometer and a GPS [global positioning system] was captured by a computer on board our boat, allowing for post-processing.
“Once I had analysed the data I was able to pinpoint the anomalies most likely to be wreck material.”

Out on the water again, they dropped anchor about 750m from shore on the two best spots, descended with scuba equipment and searched the area thoroughly.
They soon identified various wreck debris, she said.
“There was some wood, brass fastenings and loads of iron ribs, spars and plates as well as masts, and even an anchor.
“Shipbuilders only started using welding after WW2 so before that they used rivets.
“All the iron we found had rivets so we knew it was older than the 60-year heritage minimum in terms of the National Resources Act.”
Maitland and her team identified two different wrecks.
“Further investigation is needed but I believe the smaller one could be the 308-ton English iron barque L’imperatrice Eugenie which was carrying a load of wool and which went down on February 6 in 1867.”
Maitland said she believed the other, much bigger, wreck could be the 1,662-ton coal carrier Port Douglas which sank in the area in 1897.
While both these vessels hit reefs on the west side of the cape, Warren Morris’s Bay of Lost Cargoes quoted reports in the Eastern Province Herald indicating that they limped further towards the harbour before finally sinking, she said.
“Cape Recife is a real wreck trap. We know that more than 20 ships went down on the west and east side of the cape.
“These two wrecks tell a little part of that story.”..