Collision Course: the Dangers of Out-of-Date Nautical Charts
Recent Paris MoU data reveals that 7% of all ships detained were for inadequate nautical publications. Julian Macqueen highlights the dangers of using older maps as questions are raised over the accuracyof the chart data.
Julian Macqueen – Wednesday 10 February 2010
KNOWING where you are going requires a map but if that map is out of date, you could get lost. Not such a problem if it results in a longer car journey or an extended country walk. However, if a ship is the chosen mode of transport the consequences could be far more dramatic. And it would seem that the incidence of incorrect charts is on the rise.
The Paris Memorandum of Understanding on Port State Control collates information from ship inspections and detained vessels. Its December release figures for detained ships show that 3% of the causes for detention given were identified as charts. The proportion then rises to 7% if the category of nautical publications is added.
Indeed, in its 2008 annual report PSC identified a growth in deficiencies in a number of operational areas compared with 2007. One of those areas is safety of navigation. “During the campaign [on safety of navigation], 1,872 safety of navigation related deficiencies were recorded,” said the report.
It added: “81 inspections resulted in a detention where one or more Solas Chapter V detainable deficiencies were found.”
Worryingly, the most commonly found detainable deficiencies were related charts, nautical publications and the recording of voyage data.
The dangers of using out of date nautical charts have been brought home by a protection and indemnity club. The London P&I Club raised the issue in its January StopLoss Bulletin. One incident cited by the club involved a ship hitting a hazardous wreck that had not been recorded by the chart in use. The club’s investigator found that a chart correction showing the wreck had been issued three years previously.
In another incident, a submarine cable was damaged by a ship’s anchor. In this case, it was assumed the anchor had been dragged along the sea floor before coming into contact with the cable. In fact, the ship, unaware of its existence as it had been using an old edition of the chart, had dropped anchor directly above it. Apparently, the second officer had not checked whether or not he had the chart’s most recent edition.
But the problem of inaccurate charts does not stop at the ship’s bridge or with the seafarer tasked to make sure the charts onboard are up to date.
Concerns have been raised from other quarters in the maritime industry over the quality of the data upon which the charts are based. Maritime trade union Nautilus International has said that there is more to the problem than slack updating.
“In the UK, we are not confident that the quality of the nautical charts on offer is any worse or any better than those available in other parts of the world. And as we migrate towards a more electronic media, it becomes even more of a concern,” said a spokesman for the Anglo-Dutch trade union.
While it is possible the chart onboard a ship is out of date through not being updated, it is also conceivable that the original data fed into the chart is inaccurate. A case in point involved the jack up barge Octopus .
A 2007 report by the Marine Accident Investigation Bureau into this incident, which took place off the Scottish coast, found that the cause of the accident was attributable to out-of-date charts. The barge was being towed by a tug to act as a platform for the installation of a tidal turbine. However, due to strong tidal streams, the vessels changed course to a route not usually used by deep draught vessels. The jack up barge was subsequently grounded on an uncharted sandbank.
According to the area’s applicable Admiralty chart, the draught should have been above 20 m. But the barge, with legs extended to 13m, found itself stuck on the sandbank which had a depth of 7.1m. The source data for the map was found to be over 150 years old.
Responsibility for chart surveys in UK waters lies with the Maritime Coast Guard Agency.
The agency has £5.5m ($8.6m) allocated each year to achieve the hydro-mapping of the UK’s coastal waters. The funds would be enough to survey a sea area of around 10,000 sq km. But this figure should be set against a total area of 720,000 sq km of sea area.
In this situation, the agency will prioritise which parts of the seabed are in urgent need of surveying and which are not. Essentially, it is an approach based on risk. Shipping lanes in continual use by the same ship types tend to be left alone. But where there have been changes, for example, if the location of a windfarm has introduced a new edition to an accepted route or where ships’ draughts have increased, these areas will be prioritised. “We are fairly good at working out the high risk areas,” said an MCA spokesman. In the case of the Octopus , the barge had deviated from the known passage, and it was on this passage that the accident occurred.
Nevertheless, it remains the case that the base data of some surveys remains hundreds of years old.
Last year, a government initiative to move nautical mapping in the UK a step forward produced a pan-government memorandum of understanding on the sharing of hydrographic data with the MCA in the driving seat. “The aim of this approach is for the MCA to continue bringing government organisations together to encourage joint hydrographic projects and realise the financial benefits of co-funding such work,” explained the MCA in a pamphlet on the subject.
Along with the MCA, other organisations that have signed up to the MoU include the Department for the Environment, Food and Rural Affairs, the Joint Nature Conservation Committee and the British Geological Survey. One aim of the memorandum, for example, would be to make sure that different organisations are not duplicating each other’s work.
The agency has put forward a proposal to author a unified UK hydrographic survey specification partnership with the UK Hydrographic Office. In addition, its annual meeting — now called the Civil Hydrography Annual Seminar — is to provide a forum for data gathering and to foster co-operative arrangements.
The issue of keeping electronic charts updated is one part of the picture. A spokeswoman for the UK Hydrographic Office, which issues the charts, said that it recommends that nautical charts are updated regularly. The charts are searchable online and if a vessel is unable to do this at sea, it can be done before it leaves port.
There is also the point that updating nautical charts, while important, is not the most engrossing of tasks. Those are the jobs that tend to be put off for another day.
Another human aspect of the move to electronic charts is readability. Some argue that it is easier to read and note the age of the source data on paper charts. “It is harder to see the provenance of the underlying data in an electronic chart,” said one cartographer. What he is referring to is layering. That is, the facility to switch between various layers of information electronically. Data could be switched off and ‘forgotten’ by the seafarer in charge.
Then there is the question of different systems. Electronic charts are here to stay. By 2012, electronic chart display and information systems will start to become mandatory and be on board all Safety of Life at Sea Convention vessels by 2018.
Former seafarer Captain Trevor Hall, who is a director of AtoBviaC, a company which supplies accurate distances information to the industry based on electronic charts, has long experience of electronic navigational aids. He also has strong opinions on the subject. Capt Hall recognises that the Admiralty Raster Chart Service offers greater ease of visibility to the seafarer but acknowledges that their coverage is less than comprehensive. But having a good system in place is crucial.
“Compared with the cost of an accident, buying the charts, and the equipment to run them, is minimal,” said Capt Hall.
Another problem, which he feels is endemic, is the lack of proper training in using electronic navigational aids and equipment. This — the human element — is far more serious. “The user interface is different for different systems. If a system is not set up right, or people are not properly trained, you are in trouble.” That trouble can be substantial.
In 1992, the cruiseship Queen Elizabeth 2 was grounded in US waters on a shoal shown on charts to be at 39 ft but where the true depth was 30 ft. In 2008, the ro-ro passenger ferry Pride of Canterbury grounded on a charted wreck. According to the MAIB report, the ship’s officer was navigating by eye and with reference to an electronic chart system but “he was untrained in the use and limitations of the system”.
In the same year, a report into the grounding of CFL Performer found that the depth sounder was switched off on the electronic chart display and information systems display screen.