Southern waters rated for quality

Excellent water quality spots included the Clutha River sampled at Millers Flat and Lake Dunstan (above). Photo: ODT

Otago's lakes and rivers are healthier than those of neighbouring Southland waters, new Ministry for the Environment data has revealed.

Yesterday, Minister for the Environment Nick Smith announced a range of measures in the latest attempt to improve New Zealand’s freshwater management.

The package included a target to make 90% of the country’s lakes and rivers swimmable by 2040.

Data accompanying Mr Smith’s announcement revealed 81% of Otago’s rivers (by length) and 96% of lakes (over 1.5km in perimeter) had excellent, good or fair water quality for swimming based on E.coli and toxic algal level readings.

Excellent water quality spots included the Clutha River sampled at Millers Flat and Lake Dunstan.

The Taieri River had "good" water quality at Middlemarch. However, quality dropped to "fair" when the river approached Waihola, the map showed.

Much of the Tokomairiro River was found to have "poor" water quality, as  did the Tuapeka River.

Otago Regional Council chairman Stephen Woodhead said the map reflected the fact "the vast majority" of Otago’s waterways were suitable for swimming.

However, it was important to note the maps were based on data showing the water quality of lakes and rivers at a specific time, he said.

Heavy rain and other weather conditions could change the suitability of a waterway. Land, Air Water Aotearoa offered more up-to-date information on the health of waterways.

While most of the region’s waterways were shown to be in good condition, there was still room for improvement.

"We have a water plan in place which is designed to maintain water quality where it is good and improve it where needed."

The plan meant landholders were required to meet discharge limits for pollutants such as E.coli and nitrogen by 2020.

In Southland, 68% of rivers were above average and 25% were poor. Ninety-six percent of the region’s lakes were above average.

Poor swimming spots included the Mataura River and Otapiri Stream.

Environment Southland spokeswoman Adrienne Henderson advised people to give priority to information offered on the organisation’s website.

"Our website provides recent results which better reflect the local conditions."

margot.taylor@odt.co.nz