Dairy farmers are still meeting only two of the five targets set for them to avoid "dirty dairying" practices, government officials say.
Southland farmers are some of the worst offenders.
A snapshot of the latest progress under the Dairying and Clean Streams Accord between the Government, Fonterra and regional councils shows that farms have only reached or exceeded two of the five accord targets, the same overall progress as was recorded in the previous 2009 season.
The snapshot for the 2010 season measured dairy farmers' performance in meeting resource consent conditions, bridging waterways, excluding stock from streams and wetlands, and using nutrient management tools.
"A consistent effort by the accord partners is needed to improve farmer behaviour and farm system performance," Ministry of Agriculture and Forestry deputy director-general Paul Stocks said.
He said all the "easy wins" had been achieved and the sector was now "incrementally improving" .
Fonterra said yesterday that a slight increase over the 2010 season in significant non-compliance with regional council dairy effluent rules was "unacceptable".
Significant national non-compliance rose by 1 percentage point to 16%, despite considerable improvements in Northland, Auckland, Hawkes Bay, Wellington, Canterbury and Otago.
It was the second consecutive drop in performance: the previous annual snapshot showed non-compliance with regional council rules rose from 12% to 15% of farmers during the 2009 dairy season, when farmers in Northland had the worst results, with full compliance listed at 39% in the latest year, down from 43% in 2008.
This year, the worst compliance rate was in Southland (39%) and the best in Taranaki (96%).
Agriculture Minister David Carter said dairy farmers were "slowly taking heed" of his challenge to lift their game when it came to pollution.
"While progress could be faster, the message is gradually getting through to those farmers who have struggled with effluent compliance."
Mr Carter said Fonterra planned to have 1000 farms on remedial plans by the end of the season under its "every farm every year" checks of effluent management.
Fonterra's group director of supplier and external relations, Kelvin Wickham, said these checks were a concerted effort to address non-compliance by identifying farms at risk and ensuring remedial plans were put in place.
The co-operative's sustainable dairying advisers had completed 1188 consultations with farmers keen to ensure their on-farm effluent infrastructure was able to cope.
An industry body, DairyNZ - which also represents dairy companies other than Fonterra - said it had launched a "check it, fix it, get it right" campaign in Canterbury, and seen full compliance increased from 43% to 59%, and serious non-compliance drop from 19% to 8%.