Cessnock Water quality goes downhill

A recent invertebrate sample in the lower Cessnock Water, close to Hurlford, found that water quality has deteriorated markedly since the last sample taken by Ayrshire Rivers Trust in Aug 2005. Then the sample scored A1, the highest score in the Trust's scoring system, with a range of mayflies, caddis larvae, stoneflies, shrimps etc present. The picture shows an image of a flattened mayfly which were common at the site in 2005 but absent in 2009. 

The Sept 2009 sample scored D2, one of the lowest scores possible, with only pollution tolerant species present. Shrimps, which can tolerate low levels of pollution were completely absent from the sample. 

The reasons for the poor score are not yet clear although the most likely source is effluent run-off from one of the many farms in the catchment. The findings have been reported to SEPA.

Invertebrate sampling is one of the most tried and tested methods of monitoring water quality and is an excellent way of assessing the long-term health of any watercourse.