Council monitors the concentrations of indicator bacteria every week from the beginning of November until the end of March. The results of this monitoring are used to assign ‘Suitability for Recreation Grades’ (SFR Grades). The map below shows the SFR Grades for the sites currently monitored. Zooming into the map will also show the risk to your health based on the latest result as well as the most recently measured water temperature.
See more information about SFR grades
Bathing Water Quality Map
Select a location point to see details of that site.
This map is an embedded Smart Map. If you go to the original Smart Map, you will see more options, for example, you can select ‘Legend’ to find out what the colours and symbols mean.
Go to Bathing Water Quality Smart Map
The risk of catching an infectious disease from swimming in clear, clean water is usually low. However, after rainfall contamination occurs through runoff into waterways and there is an increased chance that you may catch a gut, ear, skin or respiratory infection.
The Marlborough District Council and Nelson/Marlborough District Health Board Public Health Service advise that after rainfall, it is best not to swim in discoloured water, especially for at least the first 24 hours and preferably 36 hours to minimise the risk of exposure to harmful bacteria. Further reduce your risk by:
- Avoiding areas where stormwater outlets discharge to watercourses.
- Avoiding areas with high runoff from intensive agriculture.
- A cost effective approach to measuring the concentration of microorganisms that could affect the health of swimmers is the use of indicator bacteria.
- The SFR Grade gives an overall measure of the recreational water quality of a site.
- The Council uses the ‘bathewatch’ software provided by Ministry for the Environment to assign SFR Grades.
- The MAC is calculated as the upper 95th percentile of indicator bacteria concentrations over five consecutive summer seasons.