Environmental groups are upset that rivers deemed to be ‘‘excellent for swimming’’ under new water quality standards could still make swimmers sick.
The Government announced a target yesterday of raising the proportion of ‘‘swimmable’’ rivers in New Zealand to 90% by 2040, at a cost of $2 billion to central and local government and farmers.
At present, 72% of rivers, streams and lakes were considered suitable for swimming.
Until now, the bottom line for water quality has been safe for wading and boating, not ‘‘full immersion’’ or swimming.
Environment Minister Nick Smith said the ‘‘ambitious’’ target would return New Zealand’s waterways to a standard ‘‘not seen in 50 years’’.
‘‘It will make us a world leader in water quality standards for swimming.’’
But Green Party water spokeswoman Catherine Delahunty said a river with a grade of ‘‘excellent’’ could be ‘‘so polluted that one person in 20 gets sick from a waterborne disease’’.
The new National Policy Statement for freshwater said a river was ‘‘excellent for swimming’’ if it only exceeded the threshold for faecal contamination less than 5% of the time.
‘‘The estimated risk of campylobacter infection is less than 50 cases in every 1000 exposures,’’ the statement said.
Ms Delahunty said the standard had been redefined to allow twice as much faecal contamination in rivers deemed ‘‘swimmable’’, but this claim was strongly rejected by Dr Smith.
The new water quality guideline is based on the level of E. coli bacteria in the water, which is set at 540 per 100ml.
Dr Smith said the approach aligned closely with the way European countries and the US assessed suitability for swimming.
But clean water activists said the Government had increased the E. coli setting from 260 per 100ml.
‘‘It’s a policy that will make pollution of rivers worse,’’ Choose Clean Water NZ spokeswoman Marnie Prickett said.
Land and Water Forum’s science director Ken Taylor said the change to water quality standards was more subtle.
He said the standards would put pressure on councils to clean up the very dirtiest rivers, but it would not put pressure on councils to maintain rivers that were already clean or to improve them to a pristine condition.
Mr Taylor said the Government’s policy was ‘‘reasonably positive’’ overall and ‘‘a step in the right direction’’.
For the first time, it has set a deadline for all livestock to be excluded from rivers.
The exclusion of stock had to be completed by 2030.
Lobby group Federated Farmers was not immediately critical of the proposals and said they were a ‘‘useful next step for freshwater in New Zealand’’.
