Port of Rotterdam Authority’s knotweed depot a great success

The knotweed depot in the port of Rotterdam, built four years ago, appears to have been a great success. With the help of 7,500 HGV’s, 125,000 tonnes of knotweed including soil and roots were deposited in a specially constructed ten-metre-high storage site on the Colorado Road on the Maasvlakte. By wrapping the knotweed in a special cloth, the Port of Rotterdam Authority hoped to choke the native Japanese plant. The depot has now been opened, and research shows that the experiment was a success. The Asian knotweed has been eradicated, the land can be reused, and the location let.

Four years ago, the port of Rotterdam had severe problems with knotweed. Due to its extremely strong root system, the plant can cause damage to buildings and roads and is a threat to biodiversity. To eradicate the plant, Iv has since been conducting research and testing control methods on behalf of the Port of Rotterdam Authority in consultation with Wageningen University and Bureau Stadsnatuur. And with success: knotweed is becoming increasingly less common in the port of Rotterdam. Five years ago, the Port Authority had 7.9 hectares of knotweed, which has now been reduced to around 1 hectare! When it comes to knotweed, the port currently has the most to fear from the immediate vicinity; too little is being done to eradicate knotweed permanently.

Engineering company Iv and Bureau Stadsnatuur are still active on behalf of the Port Authority at various locations in the Rotterdam port area, using various control methods. Despite the success of the knotweed depot, the work is far from over for both parties. Practical tests are being conducted at other locations using other methods, as the same working method cannot be applied universally. The varying control methods range from spraying the plant with salt water to allowing bacteria in the soil to break it down in oxygen-free conditions. The ultimate goal is to achieve a knotweed-free port area and provide port authorities with various control methods that can be used effectively at different locations.