While Environment Southland’s report on water quality didn’t bode well for the water quality of the area, a new OECD report on water quality describes the overall state of New Zealand’s water as ‘good’ relative to most OECD countries. But the report does point out the quality is deteriorating, in large part because of diffuse pollution from agriculture. New Zealand’s water quality picture was recently revealed by one of the report’s authors, Kevin Parris of the OECD Trade and Agriculture Directorate, who spoke at a water pollution conference in Rotorua on Friday.
Public opinion surveys across OECD countries in recent years have consistently ranked water pollution as one of the top public environmental concerns, and pollution from agriculture in particular is of major concern, said Parris.
“We look at all the nitrogen and phosphorus going into the system, mainly from livestock manure and fertilisers and calculate how much nutrients are used to grow crops and pasture. In most situations there is a surplus of nutrients to crop and pasture requirements which places stress on the environment (soils, water and the air). In 2000, the average for New Zealand was around 35 kilograms of nitrogen per hectare. By 2008 it was about 45 kilograms per hectare. In ten years it has gone up 10 kilograms."
In 2000, the average for the 34 OECD countries was 80 kilograms per hectare. In 2008 the average for OECD countries had come down to 65 kilograms per hectare. With not much land and a lot of cows, one of the biggest culprits is the Netherlands, with a surplus of over 200 kilos per hectare.
Agriculture is a major user of water, and with food production expected to increase by 50 percent by 2030 with a doubling production by 2050, the ramifications could be massive with further stress placed on water quality in New Zealand and worldwide.
There is a "time-bomb" effect from this agricultural expansion. Nitrogen and phosphorus can sit in soil for a long time before they appear in water.
"Because of these time lags, in some catchments, we won't necessarily see the effects of current farming practices for another 30-40 years,” said Parris.
In exploring new policy opportunities and market approaches to minimise diffuse source pollution from agriculture across OECD countries in a report to be published in early 2012, Parris examines the policy, challenges, reforms, opportunities and policy governance issues that face the sector. His findings across OECD countries reveal that policies have generally fallen short of what is required to meet water quality goals in agriculture, including in New Zealand. This is mainly a result of:
· inefficiency and failure in enforcing water pollution regulations,
· increasing budgetary costs of support to farmers to control pollution,
· frustration with the time required and institutional barriers to introduce new policies,
· lack of understanding of the scale and time delays of diffuse pollution,
· and insufficient attention to the establishment of a more inclusive stakeholder process.
Among the key policy messages from the OECD report, Parris recommends using a mix of policy ideas to address water pollution, including enforcing compliance with existing water quality regulations and encouraging cooperative approaches in water catchments that are inclusive to all the major stakeholders concerned with water pollution (e.g. farmers, environmental groups, local government).
But all is not lost. Parris said New Zealand holds the possibility to address agricultural water pollution through initiatives that include the National Policy Statement on Freshwater Management and Lake Taupo Agricultural Water Nutrient Trading scheme.