The Hogsmill Community Newsletter summarises the results of River Monitoring Initiative (RMI) sampling on the Hogsmill, together with other pollution monitoring and river-related activities and events.
The RMI is a national scheme for monitoring the health of rivers. Volunteers undertake regular surveys using a standard net sampling technique to count the number of certain “water quality sensitive” invertebrates.
An overall “score” is then calculated. A sharp fall or a drop below a “trigger” level could indicate pollution. This can then be reported to the Environment Agency (EA) to enable further investigation.