Evidence of recent pollution

This parameter is part of the newly defined UK National Protocol as part of CaSTCo. This description is preliminary and will be updated shortly.

This section covers a number of important visual indicators that pollution has occurred or there might be an ongoing threat. These indicators can span a range of ‘severity levels’ – e.g. small amounts of foam, surface scum or litter may not be a major cause for concern. Bulky waste items, sewage fungus or dead fish however would be more concerning.