Bathing Water Quality

Since 2013, Nelson City Council has invested significantly into research, monitoring, infrastructure and community engagement to meet environmental water quality and river health targets. Water quality is measured at key coastal and river swimming sites throughout the summer with results published on the LAWA Can I Swim Here module.- Here you can see what the current ‘grade’ is for your local swimming hole.

What are we testing for?

Periphytons (mix of algae, fungi, and bacteria) including Cyanobacteria is monitored/surveyed at a number of known hotspots and E.coli is measured in some of the popular swimming spots

E.coli

E. coli (short for Escherichia coli) and enterococci are a type of bacteria commonly found in the guts of warm-blooded mammals (including people) and birds. When E.coli or enterococci are found in high levels at swimming spots, it can be harmful to humans if ingested. Our summer recreation bathing monitoring program, measures E.coli at popular river swimming holes and enterococci at coastal sites weekly between December and March. Learn more about E.coli here.

Cyanobacteria (Toxic Algae)

Toxic algae (also known as Cyanobacteria) is naturally present in many New Zealand waterways. It's found in ‘clean’ rivers but can grow when river flows are low and stable, and temperatures are consistently warm. Council routinely monitors its level and informs the community when action needs to be taken. Learn more about Toxic Algae section and how this impacts our swimming spots.

Key results for recreational bathing water quality

Nelson’s beach monitoring sites at Tahunanui Beach and Cable Bay have retained Good recreation grades, with Nelson Haven (Atawhai) and Monaco (Wharf) attaining Fair grades.

Occasional exceedances (levels were above the national guidelines at the time of monitoring) have been associated with rainfall events and high spring tides re-suspending washed up debris from the beach.

The Maitai River bathing holes between Maitai Camp and Girlies Hole continue to have Fair-Good grades, with few exceedances over the last five years.

The Wakapuaka River at Paremata Flats remains at Very Poor, due to contamination from sources including livestock, feral animals, and wildfowl upstream of the sampling site.

People are advised not to swim at sites with Poor grades, which are generally unsuitable for swimming, as indicated by historical water quality results.