Riverfly Monitoring

Every month, local volunteers conduct Riverfly Monitoring on the Ash at several sites.  Their sampling technique involves a 3-minute kick sample of the river bed, and identification and counting of the aquatic invertebrates caught.  This gives a good indication of water quality and  can alert authorities to any recent pollution incidents. 

To find out more about Riverfly monitoring in Hertfordshire, or to get involved, please click here.