The boom will collect rubbish in one place
Desperate measures to prevent a rising tide of rubbish damaging an environmental preservation area are being introduced.
Cardiff Bay's new wetlands reserve has been plagued with tonnes of debris since it was created three years ago.
Now the city's harbour authority have built a floating boom to deal with the problem.
The 450-metre boom floats on the water's surface, blocking debris from entering the bay and gathering it all in one place.
In 2002, about 1,500 tonnes of rubbish had to be cleared from the water.
About 1,500 tonnes of debris had to be removed last year
David Lowe, Cardiff Harbour Authority.
"During periods of high rainfall, the water level rises and rubbish from both rivers is brought into the bay area," said David Lowe from Cardiff Harbour Authority.
"When the water level goes down again, the rubbish is left behind," he added.
The 500-acre lake and small wetland conservation area were created by the construction of a £200m barrage in the
regeneration of the Cardiff docklands.
Completed in April 2000, the barrage was built where the Taff and Ely rivers meet, creating the largest freshwater lake in Europe by separating the outflow of the two rivers from the sea.
But the barrage also prevents litter from being washed out into the Bristol Channel, so it builds up in the environmentally sensitive wetlands.
A specially-designed boat has been used regularly to sweep the lake to scoop up floating rubbish.
Now, piles are being driven into the bed of the Bay to give the new boom stability and allow it to move with the water levels.
The harbour authority is currently spending up to £200,000 on the third phase of the wetlands, making public access easier and the reserve more user-friendly.
Booms are already in use on the River Taff to collect debris from entering the ay.