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Shellfish production area assessments

How we assess shellfish production areas.
Last updated

We assess and classify a production or relaying area in line with EC Regulation 2019/627, Article 56.

A shellfish production area or relaying area cannot be classified until an assessment of the sources of pollution has been carried out. Humans and animals can be a source of contamination for the production or relaying area.

Examinations must be taken at different times of the year to show the quantities of organic pollutants released.

This can include:

  • rainfall readings
  • waste-water treatment

Circulation in the water affects how pollutants move around. We must also find out the characteristics of the circulation of pollutants in the production area using:

  • current patterns
  • bathymetry
  • tidal cycle

A sampling programme of bivalve molluscs in the production area will be based on:

  • the most accurate data from a number of samples over time
  • a geographical distribution of the sampling points
  • sampling frequency

The results of the analysis are as representative as possible for the area considered.

Sanitary surveys

Shellfish production and relay areas are affected by multiple sources of pollution. All new shellfish production and relay areas must have:

  • had assessments of the sources of pollution
  • a representative monitoring point for sampling
  • a sampling plan established

After your shellfish classification application has been accepted, we will ask our contractor to carry out a provisional assessment before a sanitary survey is completed.

We are currently considering how sanitary surveys will change in the future. During this time, provisional representative monitoring point (PRMP) assessments will be carried out for all new applications or when needed for certain amendments to sampling points.

Information assessed during a sanitary survey

The information that will be assessed is:

  • location and extent of the shellfishery
  • type of shellfishery (species, method of harvest, seasonality of harvest)
  • location, type and volume of sewage discharges
  • location of river inputs and other water courses (from OS maps/nautical charts)
  • location of harbours and marinas (from OS maps/nautical charts)
  • historical average rainfall by month
  • existing microbiological data from water quality or shellfish monitoring
  • undertaken in the same area or adjacent areas.

Provisional representative monitoring point assessment

Provisional representative monitoring point (PRMP) assessments will be carried out for all new applications or when needed for certain amendments to sampling points or areas:

  • after an application for harvesting has been verified and accepted by us, a PRMP assessment is undertaken to
  • assess pollution sources
  • identify an appropriate monitoring point
  • decide the sampling plan for the local authority to implement towards classification of the area

This does not require an on-site visit and can be carried out over several weeks.

Ten samples are required for provisional classification before any commercial harvesting can start. Each sample must be taken at least a week apart.

The sanitary survey and PRMP assessments may be used in the future by government departments or other organisations in connection with water quality investment programmes.

Survey Reports and Monitoring Assessments