Although shipowners are up in arms about shallower berths at the Port of Durban continually cutting into their vessels’ potentialpayloads, the Durban harbour master says plans are afoot for more dredger horsepower to tackle the problem head-on this year. TNPA this week received Transnet approval to build a new grab hopper dredger dedicated to the port which should be delivered at the end of 2016. Until this is delivered the Port of Durban will lease an appropriate tool. An official request for proposal is due to be issued shortly. The port, however, must be gaining a reputation amongst international seafarers as a bit of a backwater harbour – with diminishing berth depths (draughts) continually getting worse at the three main piers. TNPA says it is not maintenance dredging that is the issue.
“The dredging services division has to treat the symptoms of the problem of much bigger vessels now visiting the port and the resulting ships’ propulsion and bow thruster effects displacing material and scour at the berths. This means dredging time is doubled because you now have to dredge this scour and place it on the quayside so that it can be reinstated, as well as address the damage it causes to equipment,” said port manager, Moshe Motlohi. At the last FTW count there were six container berths (105, 107, 108, 200, 204 and 205) all working with reduced draughts – of 11.7m in four cases (105, 107, 200 and 204) 11.8m in one (108) and 11.9m in one (205). This is compared to all their original permissible draughts of 12.2m, against a total draught of 12.8m. And now, just joining this lengthening list of Transnet National Ports Authority (TNPA) berths with diminishing draughts are: Maydon Wharf Berths 10 and 11 and BCA 4. The reason, said an FTW commentator, was: “Because they’re only dredging at 107, 108 (Pier 1 container terminal) and widening the harbour.” MW10 drops from a permissible draught of 9 to 8.5m. MW 11 drops from 10m to 9.7m. BCA 4, meantime, drops from 10m to 9.6m. Surveys show the Impisi plough tug was effective at MW 9 but TNPA was unable to complete dredging work during the short 1.5 days occupation it was allowed. TNPA’s Dredging Services division says it has also been prohibited from dredging BCA because of contaminated coal found there. Motlohi says high spots are coal deposits and TNPA does not have the authority to dredge or dump coal in the dump site. This is costing the shipping lines rather a large amount of moolah as they have to sail in up on their marks. And the more of the Plimsoll line that is showing, the less the vessel’s payload.
On the container side, one shipowner’s agent worked out that, as a very approximate average, this would be costing around 1 000 TEUs per voyage (500 boxes off, 500 on). And, for the bulk or breakbulk vessels using Maydon Wharf, another line executive thumbsucked “about 20-25 000 tonnes” lost for a vessel lightloaded. And, as Peter Besnard, CEO of the SA Association of Ship Operators and Agents (Saasoa) told FTW earlier this year, shallower berths have meant that limitations have had to be imposed, bringing about a marked drop in vessel liftings and throughput through the Port of Durban. According to Besnard, this is a worrying trend that is sure to drive up the cost of doing business. But, Besnard told FTW, at a meeting last week the Durban harbour master, Captain Alex Miya, convinced the Saasoa members in attendance that he was extremely aware of the problems. And, talking to FTW after this meeting, Miya said that dredging services should see some relief through the leased dredger and the dedicated grab hopper dredger expected next year. Another big step up in dredging power is due in December when TNPA’s new suction dredger (“A big one,” said Miya) is due to arrive in SA. While the new Ilembe will not be used to dredge the DCT berths, it will help address larger areas such as the entrance channels more effectively. And the problem, Miya said, is mostly a result of larger ships now using the harbour. The additional scouring of the harbour bottom by these larger ships’ props – building up sand and rocks alongside the berths – is going to require anew dredging programme, he told FTW. “We’ll have to increase our frequency even more. We used to do it every 3-6 months. Under these conditions, berths requiring dredging every 3-6 months now need dredging every week or 2.” Meantime, TNPA is sending out a weekly dredging update to stakeholders.