E.coli found in rivers

Bathers are urged to avoid swimming at some Southland rivers after high levels of E.coli and faecal coliforms were detected.

Six sites, including two along the Mataura River, returned high samples of the pathogens in the latest round of Environment Southland testing.

The sites affected are the Waikaia River at Waikaia, The Mataura River at Riversdale, The Mataura River at Gore, Toetoes Harbour at Fortrose, New River Estuary at Whalers Bay, and the Oreti River at Wallacetown.

The Oreti River at Winton Bridge also returned a medium risk sample. Environment Southland coastal scientist Nick Ward said the elevated readings were because of high rainfall in the area over the past few weeks.

While it did not necessarily mean swimmers would definitely get sick, the risk was much higher when levels were elevated, he said.

It was difficult to predict when levels would return to low risk, he said.

''Our advice is to avoid swimming after heavy rainfall. Let the system clear."

Environment Southland uses a traffic light approach to inform the public whether the water quality of a site is suitable for swimming and other water-based recreational activity.

In marine sites, two consecutive samples with enterococci levels greater than 280 per 100ml of water constitutes a significant health risk, while in fresh water one single sample of E.coli levels greater than 550 per 100ml of water is considered a high heath risk.

The Southland Times