Waterways in the Horizons' region have become more accessible for swimming, according to an independent report which shows an improvement in sediment and E. coli levels.
Horizons Regional Council and the Ministry for the Environment commissioned a case study to understand how local interventions had impacted rivers and streams.
Conducted by LWP Ltd, the report found a 5 to 8 per cent improvement in swimmability, over the past 10 years.
The study also found local interventions were contributing on a regional scale.
Ministry for the Environment deputy secretary Cheryl Barnes said the findings would be useful for central and regional government, and showed significant progress could be made within a short period. She said the findings would also contribute to national freshwater policy development.
"The key was taking a planned, whole of catchment approach and prioritising effort and investment where it would make the most difference."
The report's author, Dr Tom Snelder, found associations between the proportion of the upstream catchment subject to land management interventions, and the level of water quality improvements.
Horizons Regional Council natural resources and partnership group manager Dr Jon Roygard said the report proved regulatory and non-regulatory interventions could effectively improve water quality.
This included targeting action to highly erodible land, upgrading point source discharges and undertaking fencing and planting of stream margins. He also said targeted interventions such as voluntary farm plans to reduce hill country erosion were in place under Horizons' Sustainable Land Use Initiative (SLUI), which was established after 2004's flood.
The scheme includes tree planting and 'retiring' erosion-prone land through letting it revert to shrub or native forest.
"To date 683 Whole Farm Plans, covering over 500,000 hectares, has included advising on 'best' farm practice and the planting of 14 million trees, and over 570,000m of waterways being fenced. Further fencing and planting has also been completed through Freshwater Grants and a Clean Up Fund project through the Manawatu River Leaders' Forum."