POTENTIAL FOR WASTEWATER MANAGEMNET USING ENERGY CROPS

In most countries within Europe there are numerous small rural Waste Water Treatment Works (WWTWs) often serving a small number of people equivalents (PEs). It is usually impractical and expensive to upgrade such WWTWs and yet they are often delivering potentially highly polluting effluent into streams and rivers. Short Rotation Coppice (SRC) willow, grown as an energy source, may be an ideal crop for the bioremediation of a variety of effluents and wastewater streams. As part of an EU funded (INTERREG IVA) project called ANSWER (Agricultural Need for Sustainable Willow Effluent Recycling) four Proof of Concept irrigation schemes were established ranging in size from 5 to 15 ha. One of the larger of these at Bridgend, Co. Donegal, Republic of Ireland was planted in spring 2013 and has been irrigated with municipal effluent since June 2014. Over 19,000 m3 of effluent has been applied to the willow thus preventing 617 kg N and 28.5 kg P from being discharged to a neighbouring stream. Using SRC willow for the bioremediation of effluent from small rural WWWTs offers a sustainable, cost-effective and practical solution to wastewater management in many countries. There may be also potential to use willow for the bioremediation of landfill leachates, within the footprint of the landfill site.