Swimming & shellfish

Environment  Southland monitors popular sites for swimming or gathering shellfish. We check these spots for bacteria that might make you sick.

We put our results on our online map, Beacon, but there are other things you need to think about too that might affect the water quality at the site you are headed to.

Using our SMART tips, you can choose a good place to swim or gather shellfish. Making a decision about where to go is all about combining the information that Environment Southland provides, along with your own observations and checks. It's easy to use our maps and SMART tips, and you can find out more about our recreational water quality monitoring here

SMART tips

Use these SMART tips to check out water quality when planning activities:


Popular sites for swimming are listed on the LAWA (Land Air Water Aotearoa) website, and Environment Southland's online mapping service Beacon, which also includes popular shellfish gathering spots. Its here that you can see the results of our monitoring.

Remember: It's important to also check for flood warnings at the spot you plan to visit using Environment Southland's water level map, which will tell you if there is a flood warning.


Swimming sites: Over summer (Dec – March) we test these swimming sites weekly for harmful bacteria. We use a traffic light system show if a site is OK for swimming. If the spot on the map is green, it's OK to swim once you have checked the additional factors and risks. If it's orange or red, it's unsafe, and you need to stay out of the water at this site.

The Beacon map for swimming displays the last four sample results for each so you can get a good idea of the recent history of water quality there.

Shellfish sites: For shellfish, we test for harmful bacteria in the water every month throughout the year at known collection sites. We use a pass/fail overall grade determine if a site is OK to gather shellfish. If the spot on the map is green, it's OK to gather shellfish once you have checked the additional factors and risks. If it's red, it's not safe to gather shellfish.

Additional factors:

Because our samples are taken weekly and water quality can change, you need to consider these additional factors before heading out to swim of gather shellfish:.

  • Heavy rain can wash contaminants or runoff  containing more illness-causing bacteria into our waterways. We recommend no swimming or gathering shellfish for at least 5 days after heavy rainfall. See Environment Southland's rainfall info here.
  • Avoid swimming near stormwater outlets.


When at the site, look around and weigh up any risks you can see before you swim or gather shellfish.

  • Check for submerged objects, swift water or strong currents.
  • Stand in knee-deep water, if you can't see your toes, the water may be unsafe to swim in.
  • If you see signs stock have been in the water or there are visible signs of contamination, keep out of the water and report this to Environment Southland.

Toxic algae:

Check your swimming spot for any excessive green/brown slime on rocks or in the water, or dark brown/black mats at the waters edge – it could be toxic. Stay out of the water and keep dogs away from the slime, and report the location to Environment Southland. Keep up to date with toxic algae alerts via our system on Beacon.

Page reviewed: 13 Dec 2017 4:18pm