Diving the Cape Peninsula and False Bay/MV Rockeater

The dive site MV Rockeater is a recent wreck in the Smitswinkel Bay area on the Cape Peninsula side of False Bay, near Cape Town in the Western Cape province of South Africa.

Understand

See also: Diving the Cape Peninsula and False Bay#Understand

The Rockeater is a relatively bulky wreck for its length compared with the frigates Good Hope and Transvaal, and is quite a bit larger than the fishing boats Orotava and Princess Elizabeth. It extends further off the bottom, and provides a larger depth range at present than the others.

Position

• S34°16.135’ E018°28.855’ MV Rockeater wreck (Bow) 📍
• S34°16.127’ E018°28.890’ MV Rockeater wreck (Stern) 📍 The MV Rockeater is the southernmost of the 5 wrecks in Smitswinkel Bay.

This site is in a Marine Protected Area (2004). A permit is required.

Name

The MV Rockeater was built in New Orleans in 1945 as a coastal freighter for the United States navy. The ship was bought by Ocean Science and Engineering (South Africa) in 1964 to be used for marine prospecting. The ship could be positioned with an accuracy of 8 metres using on-board instrumentation and shore based transponders, and could be held in place by four anchors or positioned dynamically by using the twin propellers and thrusters.

Seabed surveys were carried out using acoustic reflection profiling to map sands and gravels over the bedrock, and an airlift could be used to suck up bottom sediments for sorting and grading. The Rockeater was also equipped with a drilling derrick to take core samples. This was cut off before the ship was scuttled and lies next to the wreck on the starboard side. After twenty years of this work the Rockeater was in poor condition and no longer seaworthy. It was planned to use the ship as a naval target, but because of fears that she might sink at her moorings in Simon’s town, it was decided to donate her to the False Bay Conservation Society. The Rockeater was towed to Smitswinkel Bay on 15 December 1972 and scuttled.

| | | | Displacement | align=right | 800 | | tonnes | | Length over all | align=right | 65 | | m | | Beam | align=right | 12 | | m | | Draft | align=right | 5 | .5 | m | | Top speed | align=right | 12 | | knots | | | Crew | align=right | 40 |

Depth

Sand bottom is at about 34 m away from the wreck, and the depth alongside varies a bit. The scour pit at the rudder is quite shallow, the bottom is at about 34.7 m at high tide, while further forward it is about 33 m. The main deck is at about 32 m, and the top of the superstructure, which is the shallowest part of the wreck, at about 26 m.

Visibility

Visibility is variable, and may be quite poor at times. On a good day it may exceed 10 m, but even then it may be dark due to poor visibility in the surface waters. On a really good day visibility can exceed 15 m all the way to the surface, but this does not happen often.

Topography

The structure of Rockeater is basically intact as far as framing goes. Hull plating is still more or less intact, but superstructure plating is heavily wasted and there are big gaps between most frames. There are many openings in the deck and superstructure. Some of the superstructure has collapsed leaving only frames along the sides.

The wreck lies upright on flat sand at about 34 m, with bows to the west. The drilling derrick lies on the sand to the north west of the superstructure, and the helicopter pad has collapsed to port. The rest of the vessel is largely intact but has lost a lot of superstructure plating. The hull lies on the bottom buried to what looks like near the working waterline. Most of the rudder is buried in the sand and it appears to be bent to port, so it is possible that the lower sides of the hull have collapsed in much the same way as on the PMB. Otherwise as the draught is reported as 5.5 m, the hull must have sunk at least 4 m into the sand, which seems improbable. There is not much of a scour pit at the rudder.

There are a large number of openings into the wreck. On the waist deck there is a big rectangular hole in the deck plating and a number of smaller hatchways with raised coamings. There are several doors into the superstructure, and large areas of superstructure sides where the plating has wasted away almost completely,leaving only frames, which must be getting unstable and will no doubt collapse during a storm some time.

There is a lot of obscure structure on the deck, which was probably part of the drilling equipment, most of which has been removed or has collapsed. In good visibility the appearance should be quite impressive.

Geology: Flat fine white sand.

Conditions

The site is exposed to swell from the south east, and to a certain extent, from the south west. Longer period swell will make conditions on the wrecks uncomfortable or hazardous due to strong surge, but short period waves will just make it uncomfortable on the boat. Visibility is less predictable, and at this time is largely a matter of luck and reports from divers who were in the area recently.

The site is usually at its best in winter but there are also occasional opportunities at other times of the year, though least often in summer, when the south east wind tends to blow much of the time.

Get in

See also: Diving the Cape Peninsula and False Bay#Boat dives

This site is only accessible by boat. It is approximately 5.1 km from Miller's Point slipway and 12.4 km from Simon's Town jetty.

See

Marine life

See also: Diving the Cape Peninsula and False Bay#The marine ecology

The wreck is too deep for much seaweed, but it is heavily encrusted with invertebrates, some of which are seldom seen anywhere else but the Smits wrecks.

Features

Recent wreck of a medium sized steel vessel in fairly intact condition.

Photography

If you have good visibility and lighting, there are opportunities for some good wide angle shots, and there are enough macro subjects of various sizes to keep the critter hunters happy. Due to the depth, use of powerful strobes set well away from the camera are recommended for all medium to wide angle work. unless you are happy to settle for monochromes in green.

Routes

No particular route is recommended. The wreck is small enough to visit quite extensively on a single dive, but there is enough to see to make it worth returning. Limited but challenging penetrations have been reported.

The Rockeater is the final waypoint of the Smits Swim, a dive tour taking in all five of the Smits wrecks on a single dive, and though you don't get to stay long on any of the others, if your air supply allows, there may be time to look around the Rockeater a bit before ascent.

Stay safe

See also: Diving the Cape Peninsula and False Bay#Stay safe

Hazards

The structure has lost a great deal of strength due to corrosion, and it may be unstable. It will most likely collapse during bad weather, but should be considered a risk in a strong surge. Scorpion fish have been seen on the wrecks, and are well camouflaged. Their spines carry a dangerous venom.

Skills

Certification appropriate to the depth is expected. Some level of training or experience in wreck diving is recommended, and penetration should only be attempted by suitably competent divers after reconnaissance and appropriate planning.

Equipment

See also: Diving the Cape Peninsula and False Bay#Equipment

Equipment appropriate for the depth should be used. Nitrox is recommended for those competent to use it. A light is strongly recommended, and penetration should not be attempted without the appropriate equipment and planning. If you are not entirely certain what this would be, you are not competent to do the penetration.

Nearby

• SAS Transvaal 📍

• MFV Orotava 📍

• Good Hope Reef 📍

• MFV Princess Elizabeth 📍

• SAS Good Hope 📍

• Smits Cliff 📍

• Smits Reef 📍

• Batsata Rock 📍

Back to the Alphabetical list of sites, or list of dive sites in the Smitswinkel Bay area

Other regional dive sites:

• Dive sites of Table Bay and approaches,

• Dive sites of the Cape Peninsula west coast

• Dive sites of False Bay offshore and approaches

• Dive sites of False Bay east coast

• Fresh water dive sites of the Cape Town Metropolitan Area