Otago has some of the best water quality in New Zealand, and we want to keep it that way.

We have an extensive network of water quality monitoring sites around the region. This network helps us track the health of our waterways over both the short and long term. 

Otago's lakes and rivers are feeling the pressure of a growing population and land-use changes. If water quality deteriorates, it affects fish and other aquatic life, drinking water supplies and how we use water for recreation like swimming and fishing. 

Demand for freshwater is increasing and despite the large water volumes in some parts of Otago, other parts are among the driest in New Zealand. So, we need to manage Otago's freshwater carefully. 

State of Environment water quality

The ORC runs a long-term State of Environment (SoE) monitoring programme to measure water quality in lakes, rivers, and streams throughout Otago.  

We monitor eight lakes and over 100 rivers sites each month, measuring attributes set out in the National Policy Statement Freshwater Management to give a broad picture of the state of the waterbody. We also assess trends based on long-term water quality records.

Recreational water quality

During the summer (December to March) ORC monitors recreational water quality at 25 popular swimming spots around Otago (rivers, lakes, and beaches). The Dunedin City Council also monitor eight Dunedin beaches (Lawyers Head, Middle Beach, Sandfly Bay, Smaills Beach, St Kilda Beach, Tomahawk Beach (East and West) and St Clair. You can find the results of this weekly monitoring on the LAWA website.  

The quality of water for swimming is determined by measuring “faecal indicator bacteria” – this indicates the levels of disease-causing organisms in the water. 

We also monitor for some toxic algae (cyanobacteria), at 11 sites (5 river sites, 6 lake sites). Cyanobacteria can become a problem in lakes and rivers when large amounts are present (known as toxic algal blooms). Some cyanobacteria species are known to produce toxins which can be harmful to human and animal health. 

For each monitored site LAWA shows the most recent water quality result and the long-term grade-based results from the last five years. You can use this information to decide where and when to swim. 


How are we protecting our waterways?

We’re proposing new rules and regulations to protect Otago’s waterways for future generations. Some will be region-wide, while others will apply to specific parts of Otago. Our planning aligns with Te Mana o te Wai, a national policy framework recognising that the health and wellbeing of our waterways is of vital importance for our ecosystems and communities and must be protected as a priority. When we protect the health of freshwater, the health and wellbeing of the wider environment and communities is ensured.  

Page last updated 7 July 2024.