Water Quality Guidelines

Results from weekly sampling are compared to the Ministry for the Environment (MfE) and Ministry of Health (MoH) Microbiological Water Quality Guidelines.

Freshwater samples are graded according to the number of E. coli bacteria present, coastal samples according to the number of enterococci bacteria present.

At the end of the sampling season, each site is also given an overall score based on the number of samples that complied with the guidelines during the monitoring period.

Results are colour-coded based on whether the water sampled is unsafe, possibly unsafe (caution) or safe to swim in.

Freshwater Sites

Coastal Sites
UNSAFE >550 E.Coli/100ml UNSAFE >280 Ent/100ml
CAUTION 260-550 E.Coli/100ml CAUTION 140-280 Ent/100ml
SAFE <260 E.Coli/100ml SAFE <140 Ent/100ml