Abstract: A treatment station for a water drainage conduit has a chamber with an inlet and outlet in fluid communication with upstream and downstream sections of the conduit and a sediment collection portion. Water enters the chamber via the inlet, collecting in the sediment collection portion until it reaches a level in the chamber such that it flows out of the outlet. A filter is mountable above the sediment collection portion for the upwards-flowing filtration of water passing through the chamber to remove organic contaminants. Access means are provided for removal and replacement of the filter and removal of solid material deposited in the sediment collection portion. The treatment station may also have by pass means which operate where the flow of water exceeds a rate which can flow through the filter and preliminary sediment collection chamber for collecting large quantities of sediment. Uses of the treatment station are also described.