Via stuff.co.nz, 24-09-2011
A new OECD report will rate New Zealand’s water quality as relatively good but one of the authors is warning that while standards in other countries are improving, the opposite is happening here.
OECD economist Kevin Parris has also warned that agricultural expansion has left New Zealand facing a “time bomb” on water quality, which means the problems could worsen before they improve.
Environment Minister Nick Smith largely agreed with Dr Parris’ assessment, and said that although the Government had taken the first steps toward improvements, there was still a long path ahead to solve freshwater issues.
Dr Parris gave a presentation yesterday at an international conference on water pollution in Rotorua, and afterwards told The Dominion Post he was optimistic about New Zealand.
“But it can be that the situation gets worse before it gets better.”
He commended schemes such as the nutrient trading scheme at Lake Taupo, which had reduced nutrient flows into the lake, saying it was given a “very big tick” in the OECD report, to be produced early next year.
The Government’s national policy statement on fresh water was also promising, but Dr Parris said the Government might have to consider eventually whether it would provide some financial injections to help farmers with the work they were being asked to do.
The OECD report looked at nutrient balances by considering all the nitrogen and phosphorus going into systems and calculating how much was used to grow crops and pasture.
In most situations there was a surplus, which placed stress on the water, soil and air.
New Zealand’s nutrient balance was below many countries in the OECD.
“The difference is you’re increasing while a lot of countries are decreasing. The main reason is because the agricultural sector is expanding. That puts pressure on the water system.”
In 2000, the average for New Zealand was around 35 kilograms of nitrogen per hectare; by 2008 it was about 45kg/ha. The 2000 average for the 34 OECD countries was 80kg/ha, but dropped to 65kg/ha in 2008.
Dr Parris warned of a “time bomb” from agricultural expansion: nitrogen and phosphorus could sit in soil for up to 40 years before appearing in the water.
Dr Smith agreed that New Zealand’s fresh-water quality was relatively good, but that intensive agriculture was one factor that still presented challenges.
He said the Government had taken a collaborative approach, and had budgeted to spend $96 million from 2009 to 2014 on freshwater clean-ups. The Government was prepared to be part of funding solutions for cleaning up historical problems, but some funding would need to come from industry, Dr Smith said.