Recreational water quality - is it safe to swim?

We have a large number of popular rivers and beaches in Kāpiti. This page outlines the water quality results for rivers and beaches in our district, and also provides guidance for swimming this summer.

How we monitor water quality

We regularly monitor our beaches and rivers in partnership with Greater Wellington Regional Council. The cleanliness of the water is generally safe for swimming and other water-based recreational activities.

​Monitoring results are posted on the Greater Wellington website and their interactive map is the best way to check if the water quality at your favourite swimming spot is safe to swim.

2017/18 summer advice for swimmers

Over the past few weeks, our test results have shown fluctuating levels of bacteria, which at times have been higher than usual.

We haven’t had enough heavy or constant rain to flush out the streams and stormwater channels of rotted vegetation, and other debris which contains bacteria.

This means there’s an increased risk of getting sick with things like tummy bugs if you swim near stream and river mouths at the beach, particularly for the very young, old or vulnerable groups.

Our current advice is to still steer clear of river and stream mouths at the beach, and anywhere that has a warning in place – see GW interactive map, and anywhere where the water looks murky or there’s a lot of debris.

Advice for swimmers:

  • Be aware of the increased risk, particularly for vulnerable groups.
  • Wait two days after rain before you swim again - heavy rain flushes contaminants from urban and rural land into our waterways and we strongly advise you not to swim for at least two days (48hrs) after heavy or prolonged rainfall – even if a site generally has good water quality.
  • If you do choose to go against this advice and swim at the beach after rain, avoid putting your head under and supervise toddlers to ensure they do not swallow water.
  • Check GW’s interactive map for warnings before you head out. This gives you a general indication and of the water quality in different areas. You can select each site for full updated results.
  • Avoid swimming in streams - as a general rule of thumb, we don’t recommend swimming in streams or where streams and rivers come out at the beach, especially during hot summer months. Bacteria levels in our streams are constantly changing and at times they can often be high enough to cause illness if you come in contact with them.
  • Signage will only go up if a red/action trigger level is reached  – if test results show that the water quality has reached ‘red/action’ trigger level, then the water poses an unacceptable health risk from swimming.

More information about where and what we monitor for, and detailed recreational water info, visit

Toxic algae (cyanobacteria) in rivers and streams

If toxic algae reaches harmful levels for humans in any of our monitored recreational water sites, we’ll release public notifications to let everyone know.  

It’s normal to expect some degree of blue green algae in the Waikanae River (from SH1 to the river mouth) and in the Ōtaki River during warmer months and sometimes even during mild winters. 

There’s always a risk of harm to your dog if you let it swim or scavenge in the lower reaches of our rivers and streams, because algal blooms and dislodged algal mats can occur along the river at any time. 
For more information on toxic algae click here