School children open innovative reed bed
As part of our ongoing commitment to the environment and running a sustainable and profitable business, SWH Group has developed an innovative biological wetland treatment system, designed to treat waste water from roadside gullies, vehicle wash water and site run-off.
Once treated, the water can be recycled for washing gritter lorries and re-filling gully tankers.
Constructed at our headquarters in Rockbeare, the reed bed was officially opened on 23 July 2014 by students of Southbrook School, Exeter.
How it works
The system is a series of six cells each planted with reeds which have been specially cultivated to break down waste and contaminants from gully water. When roadside gullies are cleaned, the waste is collected and transported to our site. This waste contains sand, silt, grit, gravel, leaves, twigs, traces of oil and salt in the winter months. These contaminants mean that the water cannot be recycled until it has been treated.
The water is drained out and any solid waste is dried before being taken to a specialist facility for treatment before being re-used. The water is then filtered through a silt trap and an oil interceptor which removes any hydrocarbons before entering the first of six reed bed cells.
The reeds in these cells thrive on the impurities found in this water so take them up. As the contaminants are broken down by natural enzymes and absorbed by the reeds, good bacteria growth is encouraged which introduces natural micro-organisms to the system. Each cell has been planted with different reeds to ensure that every variety of present contaminant is absorbed.
By the time the water reaches the final cell, most of the impurities have been removed. Floating islands planted with reeds take up any residual contaminants and aerators increase the oxygen levels of the water.
Once the water completes its journey through each of the cells, it can be used for washing down vehicles, cleaning gully waste bays and refilling gully emptiers. The treatment process is carefully monitored under and Environmental Permit and water samples are regularly tested at the EA Lab in Dawlish.
What are the benefits?
Before the reed bed system was used, all gully waste (approximately 2000 tonnes per year) was taken to a specialist treatment facility and the solids ended up in a landfill site. Now, almost all gully waste is recycled in this way. Not only does this present a significant cost saving for us, but it also reduces the environmental impact of disposing of waste to landfill. Our carbon footprint is also reduced as we do not need to use large vehicles to transport the waste for disposal.
Our reed bed acts as a carbon sink and has become a new habitat for a variety of creatures. In its first year, the reed bed attracted frogs, dragonflies, nesting moorhens and even a kingfisher. Not to mention a wealth of fish which thrive in the final two cells.
The benefits of our reed bed system have been recognised by national organisations and the project was a runner up in the Devon Environmental Business Initiative Awards 2014 and finalist in the British Quality Foundation Awards 2015, as part of the Sustainable Future category.