Innovative Reed Beds Treat Heavier Loads in Smaller Footprints - Tori Sellers

Reed beds - a type of constructed wetland - have been used in municipal wastewater systems since the 1980s. But innovations are now widening their application to treat high-strength, industrial wastewaters such as landfill leachate, dairy waste, hydrocarbon contaminated groundwater and contaminated run-off.

Earlier generation passive reed beds had a limit to the efficacy of natural biological, chemical and physical forces to remove pollutants from different types of wastewater.

But that’s all changed as wetland technology’s taken a ‘quantum leap’ with Forced Bed Aeration™ (FBA™), according to Tori Sellers from ARM. FBA™ involves laying a network of pipes below the gravel matrix which bubbles air through the system increasing the oxygen availability providing greater treatment capability.

This relatively simple innovation means a sustainable technology is now available to a wide range of applications previously deemed unsuitable. Particularly difficult effluent loads can now be treated and often in small plots.

Just in time
“Changes in legislation are putting greater demands on the treatment of wastewater,” says ARM’s Tori Sellers. “Wastewater treatment systems are having to adapt to meet stricter water quality requirements.

“Reed beds have been used to successfully treat wastewater since the 1980s. Many water companies use them - Severn Trent is the largest using them at 370 sites to treat sewage and stormwater.

Southern Water has the largest reed bed treating sewage in the UK and Thames Water the second at Berkhamsted.

“But it’s over the past decade that reeds bed treatment systems have come into their own because they offer sustainability– with low energy requirements, minimal maintenance, and create habitat.

“Different environments call for different systems based on specific treatment requirements. Though they all work on the same basic principles, they are designed to cope with higher volumes or more concentrated effluents.

“We have successfully installed and operated them in a myriad of applications ranging from runoff from airports and distribution centres to the treatment of vegetable washing effluent and sewage.”