Of 536 sites examined, 49 river sites were identified with strong evidence of improving trends in E. coli concentrations.
E. coli is a bacteria commonly found in the intestines of warm-blooded mammals, including people and birds. It is often associated with intensive dairying and, while not generally life-threatening itself, can lead to more serious diseases such as giardia or Hepatitis A.
Monitoring shows the Waitekauri River has experienced an impressive 19 per cent per year trend of declining E. coli levels over the past 10 years.
"This cannot be directly correlated with any one particular action within the catchment," says council catchment management officer Warren Coffey.
"But it is likely to be the result of a combination of good work by the farmers in the catchment. This has involved a change from the past common practice of disposing of effluent into streams to land-based effluent irrigation, as well as installing bridges so cattle don't enter streams and fencing stock from streams and wetlands."
Recently the Waitekauri Valley Landcare Group carried out a survey of the catchment and, according to their data, 87 per cent of river and stream margins are fenced to exclude stock and many riparian areas have some natural or planted natives growing alongside the waterways.
There is also some community planting and weed control work occurring alongside the river around the Waikino township, which is great for the environment and the community.
"All of this work takes time and is a cost financially to the farming operation," says Warren.
"However, the rewards are visible and measurable in terms of water quality and creating a river that is swimmable.
"The regional council supports farmers who wish to carry out fencing and planting of waterways, and the landcare group helps landowners carry out further fencing and planting of wetlands and streams."
The van Woerdens have worked over the past 39 years to fence and restore waterways, streams and bush areas on their farm in the Waitekauri catchment.
"It is looking amazing now, and the challenge for all of us is to continue what we've started.
"Our landcare group was formed only 18 months ago, so we're at the beginning stages of working together in the valley.
"But over the years individual landowners have worked away on their properties making continued improvements in farm practice and management.
"This river is the most improved, and it's still improving. This award will give all the farmers in the catchment encouragement to keep up the good work and to make it one of the best in the region or even nationally," she said.