Wherever rainfall lands, it starts to flow into and through the landscape. The more we pave over the soil, converting open land into urban space, the greater the potential for flooding and pollution. The same thing happens to a lesser degree, but on a broader scale, as we drain farmland and remove space for water to rest and soak into the soil. Following are some of the solutions for repair of the hydrological cycle in our own sites, farms or river catchments.
FH Wetland Systems offers SUDS and buffer zone design and consultancy as well as plant supply and maintenance advice.
Prevention of water pollution is vital for any farm, as it is for any business. While landspreading is a legally acceptable way to spread liquid slurry, runoff from fields can be high in nutrients and can degrade local river and stream water quality. Soil and silt can readily wash into watercourses from ploughed fields while the use of fertilisers and biocides can also cause runoff pollution. To help address these potential pollution sources, local watercourses can be protected by careful use of farm scale buffer zones.
Buffer zones can help to improve water quality for fish and wildlife, as well as providing a significant measure of insurance against potential pollution incidents. Field scale buffer zones can be planted with trees for a biofuel crop; with wetland plants for filtration in unused boggy corners; or can be made into planted drains and ponds for collecting field runoff and providing storage and settlement below steeply sloping fields where soil would otherwise wash directly to the adjacent stream. Even simply widening, damming and planting farm drains can help to maximise the retention of soil and contaminants. Every small positive measure improves the overall water quality in the area.
While it is important not to cause harm to water quality or habitats, farm scale buffer zones typically fall outside of the realm of planning permissions and licencing, so can be introduced quickly and easily as a way to protect water quality on your farm without undue paperwork.
See the constructed wetland information for farm scale Integrated Constructed Wetlands for soiled yard runoff management. Note that good guidance is already available from the Department of Agriculture on these systems. In summary an ICW will need planning permission and a discharge licence and will need to be sized at twice the total yard area, including roof surfaces.
In Denmark, willow filters are used for uptake of farm runoff. This has not yet been adequately trialled in Ireland, but there is great potential in combining the high nutrient concentrations in yard runoff and the high nutrient requirements for willow growth if the willows can be used as a biomass crop as one of many products from diverse productive farms.
Farm scale composting
While adequate storage of slurry and silage effluent returns valuable nutrients to the land, a more constructive method of managing wastes is via farm-scale composting. In this way nutrient contents are maximised and bound into a healthy humic structure so that they don't run off the fields, wasting valuable nutrients and polluting waterways.
All the measures described on this page can provide beneficial habitats to wildlife, but other specific habitat creation measures can also be employed to help further support nature on your farm. See our Creating Spaces for Nature page or download our Farm Ponds notes prepared as part of the BurrenBeo Hare's Corner project.
Building soil carbon
Regenerative agriculture techniques such as holistic planned grazing, keyline ploughing, agroforestry, silvopasture and other methods can help to build topsoil and soil carbon. These have multiple benefits for water retention, drought resilience, flood control, crop and livestock health, carbon sequestration, climate resilience, biodiversity and cost savings. We can direct you to good sources of information on a site specific basis to help you explore carbon farming on your land.