Roadside infiltration beds

Roadside infiltration beds clean and filtrate contaminated road water.
The beds are often constructed using topsoil, which is a mixture of chalk, sand and compost. The soil is able to retain phosphorus, heavy metals and other anthropogenic substances in surface runoff from roads, before the water seeps down into the groundwater.
In the lower part of the roadside infiltration bed, an infiltration well can be established which be activated when the infiltration bed is full. An infiltration well has an advantage over a dry well, because it can be installed in a small area through drilling, without major excavation work.
Roadside infiltration beds are a good choice in places where there is not enough space for the infiltration beds in the verge and they must be incorporated in the roadway itself. Furthermore, roadside infiltration beds help reduce speed and they add a "green element" to the asphalt. For example, infiltration beds can be located where chicanes have already been established.