All castle lakes used in the Series will be tested for water quality to ensure they comply with the EU Bathing Water Directives listed here:
UK compliance with Bathing Water Directive (76/160/EEC)
Meeting the mandatory water quality standards of the Bathing Water Directive (76/160/EEC) is the minimum legal requirement. Mandatory standards are given for 10 parameters: total coliforms, faecal coliforms, salmonella, enteroviruses, pH, colour, mineral oils, surface active substances (detergents), phenols and transparency. The Directive also sets the minimum frequency at which bathing waters should be sampled.
Cases of non-compliance with the physico-chemical parameters are extremely rare so compliance in the UK each year is normally determined by the extent of pollution by total and faecal coliform bacteria.
To comply with these standards, bathing waters must not exceed values of 10,000 total coliforms per 100ml and 2000 faecal coliforms per 100ml in 95% of samples.
In 2010, 97.6 per cent of bathing waters in England complied with these microbiological standards, with 10 of the 413 waters failing to meet the minimum standards of the Directive.
The table below shows percentage compliance with the mandatory standards for total and faecal coliforms in England only and in the UK over the last decade.
|England % compliance
|UK % compliance
The Bathing Water Directive also sets more stringent guideline microbiological standards that Member States must endeavour to observe.
To comply with the guideline standards, bathing waters must not exceed values of 500 total coliforms per 100ml and 100 faecal coliforms per 100ml in 80% of water quality samples, and 100 faecal streptococci per 100ml in 90% of samples taken.
In 2010, 72.6 per cent of all bathing waters in England met this tighter standard. This is the guideline standard that constitutes the water quality criterion of the international Blue Flag award scheme.