Review of Sensitive Areas


The enrichment of waters by nutrients, or eutrophication, is one of the major issues for water quality in Northern Ireland, particularly in relation to freshwaters. Department of Agriculture, Environment and Rural Affairs (DAERA) is committed to a cross-sectoral approach, taking action across all sectors contributing to the problem.

Legislative background

There are three European Directives that deal with nutrient discharges into waterways:

  • the Urban Waste Water Treatment Directive (UWWTD) (91/271/EEC) 
  • the Nitrates Directive (ND) (91/676/EEC)
  • the Water Framework Directive (WFD) (2000/60/EC).

Reviews are carried out under the UWWTD and deal primarily with the management actions required by Northern Ireland Water (NIW) to protect waterways of Northern Ireland.  

Urban Waste Water Treatment Directive (UWWTD)

Council Directive 91/271/EEC deals primarily with the management actions required by Northern Ireland Water (NIW) to protect waterways from domestic sewage, industrial waste and surface water run-off, known as the EC Urban Waste Water Treatment Directive. It was adopted on May 21st, 1991. The Directive was initially transposed into Northern Ireland legislation by the Urban Waste Water Treatment Regulations (Northern Ireland) 1995 S.R. No. 12 (as amended by S.R. 2003 No. 278) and later by the Urban Waste Water Treatment Regulations (Northern Ireland) 2007 S. R. No 187.

The Directive sets minimum standards and deadlines for the provision of sewerage systems, and treatment of sewage according to the population served by sewage treatment works, and the sensitivity of receiving waters to their discharges.

If discharges from qualifying Waste Water Treatment Works (WWTWs) – which are those serving a population equivalent (p.e.) of greater than 10,000 - either directly or indirectly are found to cause (or may cause) eutrophication, or result in excess nitrate levels (i.e. >50 mg of nitrate per litre) in drinking water supplies, the receiving water bodies are identified as sensitive, and a further level of treatment than secondary is required to protect these areas within seven years of the identification. This more stringent treatment involves reducing the levels of nitrogen and/or phosphorus discharging from the works to meet the standards set in the Directive.  There is also a requirement to identify sensitive areas where further treatment than secondary or equivalent is necessary to fulfill other EC Directives e.g. Bathing Waters and Shellfish Waters

Nitrates Directive

Council Directive 91/676/EEC covers the protection of waters caused by nitrates from agricultural sources - the EC Nitrates Directive - and was adopted by the Commission on December 19th, 1991. The Directive was transposed into Northern Ireland legislation by the Protection of Water Against Agricultural Nitrate Pollution Regulations (Northern Ireland) 1996 S.R. No. 217 (as amended by S.R. 1997 No. 256 and S.R. 1999 No. 3) and the Action Programme for Nitrate Vulnerable Zones Regulations (Northern Ireland) 1999 S.R. No. 156.

The Nitrates Directive is focused on both the control of discharges of nitrates from agricultural activity.

Given the level of nutrient enrichment in our waters, and the extent of the agricultural contribution to the elevated nutrient concentrations, The Department of Agriculture, Environment and Rural Affairs (DAERA) have agreed to adopt a "total territory" approach to the implementation of the Nitrates Directive where an Action programme under the ND applies to all farms across Northern Ireland. The action programmes require farmers to observe rules to reduce nitrogen and phosphorus pollution, with measures on storing manure and periods when spreading manure and manufactured fertilizer to land is not allowed.  The first action programme was introduced in Northern Ireland in January 2007.  The Nitrates Action Programme Regulations (Northern Ireland) 2014 revoke and replace the Nitrates Action Programme Regulations (Northern Ireland) 2010, the Nitrates Action Programme (Amendment) Regulations (Northern Ireland) 2011 and the Nitrates Action Programme (Amendment) Regulations (Northern Ireland) 2012. They also revoke provisions within the Control of Pollution (Silage, Slurry and Agricultural Fuel Oil) Regulations (Northern Ireland) 2003. There is currently a review underway of the Nitrates Action Programme Regulations (NI) 2014. The proposed amendments reflect the new values for the Nitrogen and Phosphorus contents of poultry litter as a result of further research which was carried out.  This together with other controls such as the Phosphorus (Use in Agriculture) Regulations Northern Ireland 2014 is designed to reduce nutrients from agriculture that contribute to eutrophication.  

The goals of both Directives are complementary and aimed at reducing nutrient inputs into waters from the urban and agricultural sectors.

The Water Framework Directive

Although the term eutrophication is not explicitly defined in the WFD itself there is a requirement to classify each water body in terms of its ecological status as high, good, moderate, poor or bad.  This is determined by combining assessments results for biological (biomass/abundance of plants/algae) and physiochemical quality elements (nutrients, dissolved oxygen), with the quality element most severely affected by human activity determining the overall ecological status.  To achieve good status the biological elements must show only slight signs of disturbance caused by human activity – or undesirable disturbance.

The Water Framework Directive requires Member States to prevent any further deterioration in the status of water bodies, where technically feasible and not disproportionately costly, to restore water bodies to good status.   

In practice, the measures required by the UWWTD, ND and WFD are now integrated to ensure appropriate controls over all significant sources of nutrients.  WFD nutrient and ecology standards are used to identify eutrophic water bodies which can then be identified under UWWTD or ND. Sources of nutrients can then be controlled via the standards under the UWWTD, action programmes under the ND or by supplementary controls or measures under WFD.  

Full implementation of both Directives is fundamental to the achievement of the Water Framework Directive (WFD) target of Good Ecological Status for all fresh, coastal, estuarine waters by 2015. 

UWWTD Review process

Member States are required under the UWWTD to review the trophic or nutrient status of all their water bodies (coastal, estuarine and freshwaters) every four years and identify which areas meet the criteria in the Directive. Assessments for the review are carried out on the basis of scientific criteria and evidence agreed by the UK.  Once identified more stringent treatment at qualifying sewage treatment works within seven years.  

Waters may be identified as 'Sensitive (Eutrophic)' if found to contain excessive levels of nutrient waste as outlined by both the UWWT or Nitrates Directives, or likely to become eutrophic if preventative action is not taken. Areas requiring a ‘Sensitive Area (SA)’ identification under Annex IIAc of the UWWTD, (i.e. those areas where further treatment than that prescribed in Article 4 such as bathing waters or shellfish waters) are also considered.  All waters draining the catchments of the sensitive receiving water are included in the designations.   

The SA review process in Northern Ireland is undertaken by the Water Policy and Finance and Co-ordination Unit and the Northern Ireland Environment Agency (NIEA). Once an area has been identified as sensitive or potentially sensitive to eutrophication, qualifying WWTWs discharging either directly or indirectly into a Sensitive Area will be obliged to remove all phosphorus and/or nitrogen to Directive standards within seven years. The Directive also includes thereafter a requirement to review all Sensitive Areas every four years and report to the European Commission.

Designated areas

The freshwaters of Lough Erne and Lough Neagh were formally identified as SAs (Eutrophic) in 1994. Following a review in 2001, a further three areas were identified: Inner Belfast Lough, the tidal River Lagan, and the Quoile Pondage at Downpatrick.

In 2006, following the 2005 review, the number of areas identified was increased to 16 bringing the total land area of Northern Ireland draining the catchments of waters identified as sensitive areas to approximately 85%.  These designations included eight freshwater bodies and their catchments and three marine water bodies and their catchments as follows: North Strangford Lough (bounded by the co-ordinates 54o 30’ 26N 5o 02W, 54o 30’ 40’N 5o 33 05’ W), Newcastle bathing water, Ardmillan shellfish water (modified in 2009 and now known as Paddy’s Point and Reagh Bay), the River Lagan, Enler river, River Bush, Newry river, Lower Bann river, River Roe, River Faughan and Foyle River.

The 2009 review did not identify any further water bodies as Sensitive (Eutrophic).  However Ballyholme and its catchment in Co. Down was identified as sensitive under Annex IIAc due to continuing bathing water failures.  A new WWTW at Donaghadee serving Bangor, Donaghadee and the wider area was commissioned in 2007 and has both nutrient removal and bacterial reduction. Despite these improvements, Ballyholme bathing water is still vulnerable to poor water quality events in wet weather. This has been attributed to sewerage infrastructure and catchment issues.  The area has been identified under Annex IIAc in the 2009 Review to drive improvements in the sewerage infrastructure system in Bangor. Catchment Studies are ongoing to identify other pollution sources.

Although Inner Dundrum Bay was not identified as sensitive under the 2009 review, it did fail the WFD assessment on two criteria; winter nutrients (Dissolved Inorganic Nitrogen - DIN and the Macroalgal Blooming Tool - MBT). The report recommended further monitoring and assessment to be carried out. In 2012 an Interim Sensitive Area Review of Inner Dundrum Bay was conducted and identified both the Bay and its catchment area as a SA(E).  A designation was also made under Annex IIAc (shellfish water) with effect from 1st August 2014.

The 2015 review identified two further designations. The Castletown Catchment displayed characteristics symptomatic of eutrophic conditions or ‘may become eutrophic if protective action is not taken in the near future’. This catchment crosses the international border with the Republic of Ireland and discharges into the Castletown Estuary which was identified as a Sensitive Area under the UWWTD[1] on 14th June 2001. The Newry River transitional water body was also identified for designation as a Sensitive Area (Eutrophic) having shown a deterioration in both nutrient and plant status over the period of the report.

The two designations came into effect from December 2015, bringing the total existing area of land draining to water bodies which are sensitive to eutrophication to approximately 86%. The 2019 UWWTD Sensitive Area Review is currently underway.

[1] Urban Waste Water Treatment Regulations 2001, S.I. No 254 of 2001,




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