Friday, 15 July 2016


The Meliskerk, a steel hull cargo vessel, was built in Hamburg, 1919. She was almost the length of the Waratah, 450 ft, with gross tonnage 5919, and powered by a quadruple expansion steam engine, making 12.5 knots. The Meliskerk was initially known as the DADG76, and later the Cesario. In 1921 she was bought by the United Stoomvaartmaatschappij, Dutch Africa Line, and renamed SS Meliskerke.

January 1943, under the command of Captain Brouwer, and loaded with 11 000 tons of ammunition, tanks and three aircraft, steamed along the Wild Coast, South Africa. In an attempt to avoid enemy submarines, the Meliskerk hugged the coast. Northeast of Port St Johns, between the mouths of the Umzimvubu and Mzintlava Rivers, she struck a reef and foundered rapidly in 15 m of water.

Salvage attempts recovered 500 tons of cargo but rough seas caused ammunition to explode, disrupting further efforts. The wreck of the Meliskerk is a popular diving site and home to a unique array of marine life. 

Why is the Melliskerk visible and Waratah not - if she is there?

The suspended load, on the other hand, is the amount of sediment carried downstream within the water column by the water flow 11. Suspended loads require moving water, as the water flow creates small upward currents (turbulence) that keep the particles above the bed 13. The size of the particles that can be carried as suspended load is dependent on the flow rate11. Larger particles are more likely to fall through the upward currents to the bottom, unless the flow rate increases, increasing the turbulence at the streambed. In addition, suspended sediment will not necessarily remain suspended if the flow rate slows.

In marine environments, nearly all suspended sediment will settle. This is due to the presence of salt ions in the water. Salt ions bond to the suspended particles, encouraging them to combine with other particles in the water 15. As the collective weight increases, the sediment begins to sink to the seafloor. This is why oceans and other marine ecosystems tend to have lower turbidity levels (greater water clarity) than freshwater environments 15.

Furthermore, in a tidal zone, the constant water movement causes the bottom sediment to continually resuspend, preventing high water clarity during tidal periods16. The clarity of an estuary will depend on its salinity level, as this will assist with particle deposition .

Onshore wave and tide turbulence creates conditions as described above with sediment in suspension rather than deposited, whereas further out - say 0.5 miles - the sediment deposits on the ocean floor, no longer supported by bed turbulence. 

Melliskerk - very visible, close to shore.

Note site marked on map within zonal sediment 


Mole said...

Amazing content in this post, Andrew,love it, and what a remarkable pic of the Meliskerk.

andrew van rensburg said...

Thank you Mole.

Anonymous said...

Meliskerk was visible before blowing up because the captain deliberately beached her after striking rocks. If the Waratah had have struck St Johns Reef she would have also been highly visible above the waterline because the is only 6feet of water over the rock at low springs.

andrew van rensburg said...

My contention, if Waratah did in fact strike St Johns reef, is that it was a glancing blow and she continued for a further 0.5 miles out to sea before foundering.

Anonymous said...

Waratah would have grounded in the sand before hitting the reef
bearing in mind you said she had a draught of 28ft 8" or 8.76 metres
the sandy bottom near the reef is 5 metres deep.

andrew van rensburg said...

Thank you for your important comment. However, the furthest protrusion of the reef, as per chart (St Johns Reef - key to the mystery post) drops to a depth of 18 meters = 59 ft.. +/- tide influence.