SOUTHAMPTON'S container port is set to almost double in capacity, bringing an avalanche of more than 600 new jobs, the Daily Echo can reveal.

In one of the most important business developments in the history of the docks, the port will see an investment of hundreds of millions of pounds to increase capacity by 85 per cent.

The move equals the scale of the controversial Dibden Bay proposals but using only existing port land in the Western Docks.

Port bosses say the plans "kick Dibden Bay into the long grass" but emphasise that the development remains a long-term goal.

In an announcement later today, they will explain how they plan to increase the number of containers handled to 3.7 million every year - level with Britain's biggest container port, Felixstowe.

Fears dismissed The next generation of 400m-long container ships, which can carry as many as 12,000 containers, will become a familiar sight on Southampton Water once the work is completed in 2010.

After the £600m Dibden Bay plan was rejected on environmental grounds, port owner Associated British Ports is emphasising the sustainability of its proposals.

Fears that the increase in container numbers would see as many as 6,000 extra lorries each day - four every minute - were dismissed by ABP. Instead the port giant, which was taken over by a consortium of foreign financiers in a £2.8 billion deal earlier this year, aims to send many of them out of the city by water on small feeder ships.

Bosses hope that the massive expansion will also persuade the government to upgrade the railway from the port, which has bridges too small to fit the latest generation of containers.

Technological advances mean that containers can be stacked higher so the port can fit more on to a similar footprint of land.

The plans follow a major business win from rival Thamesport, which saw Southampton sign a deal to receive 250,000 extra containers annually and raised the prospect of the container port being full to capacity within a few years.

When complete, Southampton will move up from being Britain's second-largest container port to be level with Felixstowe, which has claimed top place for many years. However, even at 3.7 million containers it will still be dwarfed by foreign trade giants such as Singapore, which handles a massive 22.28 million containers annually.

The exact scale of the investment from ABP is unclear but Southampton port director Doug Morrison said that it would be "in the hundreds of millions rather than tens of millions".

The number of new jobs to be created is also not known but if recruitment followed the level of business expansion, the final figure could be as high as 680, with many thousands of other new jobs created in businesses dependent on the port.

Containers and the ships that carry them are the lifebood of the global economy and Southampton is set to become one of the main arteries for this international trade.

Everything from electrical goods and food to trainers and toys arrive in stores up and down the land after making their way through Southampton from all over the world.

Southampton handles seven per cent of UK seaborne trade, bringing more than £2 billion of business to the local economy and directly supporting 12,000 jobs in the region. Half of all UK trade with the Far East comes through the city.

Job security Mike Gibbons, the Transport and General Workers' Union convenor at the docks, welcomed the news: "It gives job security and a future for everybody, not only those who work here but everyone connected with it.

"The whole region will benefit. It is great news for Southampton and it ticks all the boxes, including sustainability because it's on existing port land.

"It will also give us a big increase in the number of jobs when it comes to fruition."

ABP chief executive Bo Lerenius said: "Having learned much from our recent successful developments on the Humber and from the protracted Dibden Terminal application process, we believe our current strategy for South-ampton represents one of the most sustainable container expansion plans currently being considered in the UK."

However, environmentalists warned that the scheme, which requires significant dredging, would not be without an ecological cost.

Jolyon Chesworth, marine conservation manager for Wildlife Trusts in the south east, said: "Dredging is a very big problem. You are removing large amounts of sediment so any of the plants and animals that live on it or in it will be removed. They can't discriminate."