Issues Within The Boyne Catchment
The river Boyne provides a wonderful service to the community. It provides us with a place to enjoy nature and to take part in activities centred around the river. However, it also provides another valuable service. It takes significant amounts of human created pollutants and waste and removes them for us. It has a natural capacity to do this, but it is reaching the limits of it’s ability to clean up after us.
Water Framework Directive
Under the Water Framework Directive Ireland has agreed to ensure that all it’s waters will be in High and good ecological status by 2027. As things stand, Ireland is falling very short of this target and the Boyne catchment is no exception with many water bodies failing to achieve an adequate ecological status in the past 5 years. The 3rd cycle of the river basin management plan has identified that within the Boyne catchment only 65 waterbodies are in good or high status and 79 in moderate & poor status.
Waterbody Status Breakdown
This table illustrates the change in status between Cycle 2 (assessment based largely on 2010-2015 WFD Monitoring data) and Cycle 3 (assessment largely based on 2013-2018 WFD monitoring data).
Over this period 20 (14%) waterbodies have improved in status, 101 (70%) waterbodies have remained unchanged and 23 (16%) waterbodies have declined in status.
There is an overall decline in the status of three waterbodies across the catchment since the Cycle 2 assessment.
The significant pressure affecting the greatest number of waterbodies in the Boyne Catchment is agriculture, followed by hydromorphological pressures, domestic waste water, peat, urban waste water, urban run-off, industry and mines & quarries. Impacts on waterbodies related to agriculture include phosphorus loss to surface waters from, for example, direct discharges; or runoff from yards, roadways or other compacted surfaces, or runoff from poorly draining soils. Sediment associated with agricultural activities, including land drainage works, bank erosion from animal access or stream crossings, has also been noted as an issue in this catchment. Organic pollution associated with run-off from farmyards in particular, has also been identified throughout the catchment.
Agriculture
Significant issues arise from unsuitable domestic wastewater treatment systems, especially when they are poorly sited on areas with high pollution impact potential/poorly draining soils or discharging directly into the water bodies. This results in enrichment and organic contamination. Furthermore, some of these locations are located on areas of high susceptibility to phosphate transport via near surface pathways.
Domestic Wastewater Discharge
This refers to discharge from municipal wastewater treatment plants that discharge into the catchment. Urban wastewater agglomerations have been identified as a significant pressure in eight ‘At Risk’ river waterbodies in the Boyne catchment, as well as Ramor lake and the Boyne Estuary.
Urban Wastewater Discharge
This refers to man made changes to the natural course of a river. For example, hydromorphology can include locks and weirs, dams, canalisation, land drainage. The Boyne has been highly modified through out the past 5000 years, but the most notable and detrimental changes occurred because of the arterial drainage scheme. Channelisation is the dominant hydromorphology subcategory in the catchment with 34 river waterbodies within the catchment subject to extensive modification mainly due to drainage schemes. These hydromorphologic issue can disrupt the migration and spawning of fish and aquatic species, such as salmon, eels and otters. Hydromorphologic issues can also cause waterbody water temperatures to increase during periods of severe drought and can increase water flow intensity during floods. These can all have significant impacts on the habitats within the catchment.
Hydromorphology
