State of the Park

Llyn Mymbyr, Snowdonia

alt=View from Snowdon Summit

Water Quality

WFD Classification

The way that waterbodies are assessed has changed significantly as a result of the introduction of the WFD. Previously, the General Quality Assessment (GQA) scheme was used to assess river water quality in terms of chemistry, biology and nutrients. The WFD classification looks at over 30 different measures, grouped under two main headings:

  • ecological status (this includes biology as well as other factors such as phosphorus and pH) and
  • chemical status (‘priority substances’ e.g. mercury).

In addition to rivers the WFD also covers estuaries, coastal waters, groundwater and lakes. As a consequence NRW have had to update existing assessment techniques and develop new ones for those indicators not previously assessed.

River Basin Management Plans

Under the Water Framework Directive, Natural Resources Wales is required to produce River Basin Management Plans (RBMP) that describe the pressures facing the water environment in each of Wales’s three river basin districts6 on a series of six-year planning cycles. The second tranche of RBMPs is to be published in December 2015.

Each plan outlines the actions needed to improve the water environment. They also list the benefits that can be achieved and those best placed to deliver them. The Snowdonia National Park lies partly in the Western Wales RBD and partly in the Dee RBD.

View the status of water bodies in Snowdonia

Status of catchments in Snowdonia

The status of water bodies in Snowdonia can be viewed at: Water Watch Wales

Water Quality Map

(© SNPA 2016)

Key to Map

 Bad
 Good
 High
 Moderate
 Not yet assessed
 Poor
 Removed coastal water body

Reasons for Failure for Water Bodies in Snowdonia

NRW use reasons for failure (RFF) information to identify the main factors and issues impacting on Wales’ water environment. Some failures may be caused by upstream issues (e.g. over-abstraction or regulation of flow) or downstream (e.g. obstructions such as weirs and dams can prevent fish migration). These issues occur across catchments and water bodies.

The main reasons for failure that Local Authorities should be able to address have been identified:

  • Artificial barriers to fish migration
  • Abandoned mines & contaminated land
  • Sewage discharges
  • Flood protection & land drainage
  • Urban & transport development

The table below shows all of the reasons for failure that NRW have identified for water bodies in the Snowdonia National Park. In many cases water bodies fail for multiple reasons.

Reason for FailureNumber of times RFF identified
  Abandoned mines and contaminated land33
  Acidification27
  Agricultural pollution9
  Barriers to fish migration10
  Flood protection and land drainage5
  Forestry15
  Industrial discharges33
  Natural conditions3
  Septic tanks19
  Sewage discharges1
  Surface water abstraction3
  Urban and Transport development1
  Other1
  Unknown5

In order to achieve Good status many different co-deliverers need to take action utilising, where possible, existing mechanisms and measures to deliver cost-effective sustainable improvements to the waterbody in question.

6 A ‘river basin district’ is a group of catchments that contains a collection of rivers, lakes, groundwater reserves and coastal waters.