Surface water status indicator
The Water Framework Directive (WFD) is an important mechanism for assessing and managing the water environment in the EU, through a 6 yearly cycle of planning and implementing measures to protect and improve the water environment. This indicator shows the percentage of surface water bodies in each status class and the change in the percentage of water bodies in the UK awarded a good or high surface water status class under the WFD. Around 10,000 water body assessments are included each year of the indicator; including rivers, canals, lakes, estuaries and coastal waters.
There has been a small decrease in the overall number of surface water bodies in the UK awarded high or good status between 2012 and 2017. In 2017, 35% of surface water bodies were assessed under the Water Framework Directive (WFD) as being in high or good status compared with 36% in 2012; the indicator is assessed as declining in the short term.
UK surface water bodies
Status classification of UK surface water bodies under the Water Framework Directive, 2009 to 2017.
- (WFD) in England, Wales, Scotland and Northern Ireland. Includes rivers, canals (Northern Ireland does not report on canals), lakes, estuaries and coastal water bodies.
- A water body is a management unit, as defined by the relevant authorities.
- Water bodies that are heavily modified or artificial (HMAWBs) are included in this indicator alongside natural water bodies. HMAWBs are classified as good, moderate, poor or bad ‘ecological potential’. Results have been combined; for example, the number of water bodies with a high status class has been added to the number of HMAWBs with high ecological potential.
- The results published each year relate to data reported in that year under the WFD; data reported in a given year relates to data collected over the previous year. From 2016, England, Wales and Northern Ireland have moved to a triennial reporting system. Wales and Northern Ireland reported in 2015 and will report next in late 2018; England reported in 2016 and will report next in 2019. Classifications are valid until they are next assessed; therefore, for years where a country does not report, their latest available data are carried forward.
- The percentage of water bodies in each status class has been calculated based on the total number of water bodies assessed in each year.
- The number of water body assessments included varies slightly from year to year: 10,835 water body assessments were included in 2009; 10,763 were included in 2010; 10,783 in 2011; 10,705 in 2012; 10,764 in 2013; 10,799 in 2014; 9,297 in 2015 and 2016; and 9,298 in 2017. These figures have been revised since the 2016 publication.
- The reductions in the number of assessments made in 2015 were due to England, Wales and Northern Ireland adopting the monitoring and classification standards laid down in cycle 2 of the WFD. This means that data from 2014 onwards (when Scotland adopted the cycle 2 monitoring and classification standards) are not directly comparable to those in earlier years.
Source: Department of the Environment Northern Ireland, Environment Agency, Natural Resources Wales, Scottish Environment Protection Agency.
Assessment of change in status of UK surface water bodies
|Long term||Short term||Latest year|
|Percentage of UK surface water bodies in 'High' or 'Good' ecological status||
|No change (2017)|
The WFD specifies the quality elements that can be used to assess the surface water status of a water body. Quality elements can be biological (e.g. fish, invertebrates and plants), chemical (e.g. heavy metals, pesticides and nutrients) or indicators of the condition of the habitats and water flows and levels (e.g. presence of barriers to fish migration and modelled lake level data). Classifications indicate where the quality of the environment is good, where it may need improvement and what may need to be improved. They can also be used, over the years, to plan improvements, show trends and monitor progress.
The ecological status of UK surface water bodies is a measure that looks at both the biological and habitat condition status of a water body. Some small differences exist in the way the administrations and environment agencies implement the methods and tools for assessing water body status.
The introduction of new WFD monitoring data and classification standards (including a new baseline adopting all of the new standards, tools, designations and water body boundaries) in 2014 has led to a step change in the number of water bodies assessed as being in each status class in following years. It also led to a reduction in the total number of water bodies being assessed because under the new WFD guidance, water bodies below the 10km2 catchment area no longer need to be included. The formal reporting of new standards in cycle 2 of the WFD has used the second cycle plans published in 2015. The introduction of reporting the cycle 2 standards has differed amongst the UK countries (see background section for more detail).
Last updated: July 2018
Latest data available: 2017