An environmental scheme that will improve the quality of the River Medway is reaching its final stages.

We have invested £4.2 million to upgrade Ham Hill Wastewater Treatment Works, in Snodland, Kent.

Work has included a new pumping station and two 22-metre diameter tanks, which wastewater trickles through during the final treatment stage.

The tanks contain millions of bugs which break down contaminants in the wastewater, adding an extra – and completely natural – stage of treatment.

Two one-metre diameter snail traps have also been fitted. These will be to prevent small snails - which can thrive in the wastewater – blocking the filters.

Construction at the site is now complete and testing of the new equipment is taking place.

About 12 million litres of wastewater flow through Ham Hill treatment works each day in dry weather, rising to 30 million litres per day in wet weather.

The new scheme will also ensure the site can support the area’s predicted population growth – it currently serves a population of 42,000, a figure expected to rise to 46,000 by 2020.

Construction, which started in December 2010, was carried out by contractor 4Delivery.