forestry

Forest harvesting can cause severe disruptions to the hydrologic cycle. Clearcut areas are often subject to localized flooding due to reductions in evapotranspiration caused by removal of trees. Roads and other infrastructure needed to support forest harvesting can also be significant sources of sediment to surface waters. However, negative effects can be minimized when forest harvesting is performed in a water-sensitive manner and measures are taken to maintain the natural hydrological functioning of the landscape.

Appropriately designed roads and stream crossings can minimize the likelihood of erosion and sediment production that can be associated with forestry activities including final harvest. Poorly designed or built roads and stream crossings can cause some of the most negative effects of forestry on the landscape. Well-designed roads follow the contours of the landscape. Roads which run up and down (instead of across) hills can act as channels which focus runoff and can lead to increased erosion. Properly designed stream crossings permit the free movement of fish and aquatic invertebrates and will not restrict peak flows. Ensuring that stream crossings do not restrict peak flows will help to reduce localized flooding and can ultimately be more cost effective as they will not need to be rebuilt following high flow events - Based on Stella definitions, adapted by NWRM project experts and validated by the European Commission