2. Riverfly Monitoring on the Middle Lea

Themes: Water quality; Public engagement


  • Reduce chemical pollution
  • Improve public engagement with the river

Project description

This project will establish a new Riverfly Monitoring Group along the Middle Lea.

 Riverfly monitoring is a national scheme whereby local volunteers are trained in how to sample for an identify a range of freshwater invertebrates.  Every month, pairs of volunteers will monitor the same site on their local river, building up a picture of the river's health and generating a score for the river each month.  If this score drops below a certain 'trigger level', it indicates there has been a pollution event and the Environment Agency will come and investigate.

Riverfly Monitoring is often described as a 'neighbourhood watch scheme for rivers'.

On the Middle Lea, the next steps in the riverfly monitoring scheme will be to work with the Environment Agency to agree up on which areas will be established as sampling sites. Then, monthly sampling can take place to determine which invertebrates are present in the river, and in what quantitites. 

For more information please click here.

Project lead: Chilterns Herts and Middlesex Riverfly Hub
Project partners: Local landowners and volunteers
Funding source: Affinity Water, Natural England, Colne Angling Consortium
Project start: 2014
Project end: Ongoing
Contact for more information: This email address is being protected from spambots. You need JavaScript enabled to view it.
Riverfly Monitoring in progress

Design by LTD Design Consultants and build by Garganey Consulting.