Canterbury's Pahau River took out the Supreme Award for Most Improved River at the New Zealand River Awards 2017 in Wellington last night.
Pahau River is surrounded by dairy farms, yet E. coli in the water improved by an impressive 15.4 per cent per annum over the past 10 years.
Dr Morgan Williams, Chair of Cawthron Foundation and NZ Rivers Trust said there had been a shift to more efficient irrigation techniques, and better farm management practices in response to tighter nutrient rules imposed by regional councils.
"These changes, plus a commitment to riparian fencing and planting, have almost certainly contributed to the marked decline in E. coli. Science, goodwill, and hard work can help restore river health.
"What's happened in this catchment highlights the importance of taking a systems approach: setting nutrient rules, adopting more efficient irrigation methods, and pursuing innovative farm management practices," said Dr Williams.
Stricter nutrient rules imposed by ECan, and pressure from the farmer-owned Amuri Irrigation Company, have driven farmers to invest in more efficient irrigation systems. The company has also led a project to convert open race water distribution to under-ground piped distribution.
The Supreme Award recognises long-term improvement in a specific water quality indicator. E. coli was the indicator used by judges this year, and they determined the winner based on independent LAWA monitoring data.
Professor Gillian Lewis was on the scientific judging panel and said, "E. coli is primarily an indicator of human health risk, and while not directly an indicator of ecological health, it is often correlated with other contaminants that affect river health such as sediment and nutrients."
Scientists judging the awards strongly support initiatives to improve the consistency of freshwater monitoring programmes. Professor Lewis said, "We want to ensure consistent methods are used for sampling and laboratory analyses, so robust trend analyses are possible."
Other awards announced include the River Story Award and Reo mo te Awa (River Voice) Award:
- The River Story Award went to University of Otago staff and students for their ExStream project experiments on freshwater. This pioneering system has been replicated in several countries and is currently being used to see how climate change plus pesticide use might impact on water quality.
- Marnie Prickett received the Reo mo te Awa (River Voice) Award for her strong advocacy of New Zealand's rivers. She is part of a team driving for freshwater policy changes, so current and future generations can enjoy healthy, safe fresh waterways.
Dr Williams is encouraged as more councils, communities and individuals now recognise that the cumulative impact of many actions can help river health.
"There's an increasing change in attitude, particularly among farmers, that they have a responsibility to adopt practices to improve the health of our waterways. A combination of encouragement, publicity and coercion will keep this transformation going," said Dr Williams.
The New Zealand River Awards 2017 were run by Cawthron Foundation, with generous support from others wanting to improve the health of our rivers and lakes.