The Green Party yesterday criticised the need for signage warning of health risks going up on the Taieri River at Waipiata after high levels of E.coli were recorded there.
''More intensive farming and weak rules increases the risk of more faecal contamination of our rivers, making them unsafe for swimming, as is happening in Otago's upper Taieri River,'' Green Party water spokeswoman Eugenie Sage said.
The Government was seeking feedback on proposed base lines for water quality and its changes to the National Policy Statement for Freshwater Management.
''The Taieri River is another example of why the Government needs to strengthen its proposed national bottom line so that our rivers are clean and safe for swimming,'' Ms Sage said.
It should be compulsory that regional councils manage land use so people could swim in the country's rivers.
Otago Regional Council engineering, hazards and science director Gavin Palmer said the council already had strong water quality rules and Water Plan 6A (water quality) proposed an E.coli level much lower than the proposed national standard.
Under 6A, the E.coli standard was set at 550 colony-forming units (cfu) per 100ml, while the national standard was less than 1000 colony-forming unit (cfu) per 100ml.
That standard had been agreed to through consultation and mediation with the Otago community, he said.
''The standard is much more stringent than what the Government is proposing.''
As for putting up signage warning of the contamination, it was the council's responsibility to advise the public so they could make an informed decision about swimming or using the waterway, Dr Palmer said.
No conclusions could be made about what was causing the contamination. Council staff had been unable to find the cause and there was no consistent trend in terms of the sample results so far.
''Weather could be an influence but it could be one of many factors. We're determined to get a better understanding of what is causing it,'' Dr Palmer said.
