Farmers in the Eastern Bay of Plenty are being given credit after the Nukuhou River won the region's 'most-improved” title for 2015.

The award is a tribute to landowners' efforts in the eastern catchment, says Bay of Plenty Regional Council chairman Doug Leeder, who was speaking at the Morgan Foundation's annual River Awards ceremony in Wellington.

The Nukuhou River is the biggest tributary of Ohiwa Harbour. Photo: File.

'It recognises the hard work landowners have done to protect the river over the past several years,” says Regional Council eastern catchments manager Simon Stokes.

Most improved rivers are determined by the trend decline in dissolved inorganic nitrogen (DIN). The Nukuhou River has recorded a 3.4 per cent decline in DIN since 2005, which continues a steady trend that has been evident since 1995.

Landowners installed bridges and culverts for stock crossings, riparian fencing and planting and upgraded on-farm effluent management systems - activities considered contributors to the trend decline in DIN in the catchment.

Regional Council became involved about 10 years ago, providing technical expertise and financial support at the landowners' request.

Since then, farmers installed another 49km of riparian fencing, built six bridges to allow stock to cross the river without walking through the water and upgraded stock races to avoid run-off going directly into the streams.

They also retired and planted a further 333ha of steep land, and planted 48,000 native plants, mostly on riparian margins.

Clearing unstable trees and stream bank battering, grassing and planting has been carried out to reduce the sediment load in the river.

'The Ohiwa Harbour Implementation Forum and Ohiwa Harbour Strategy Care Group have also worked closely with council and have played a huge part in improving the river,” says Simon.

'The forum has done a fantastic job overseeing river projects and monitoring council's work with landowners to ensure the Ohiwa Harbour strategy delivers for the environment.”

Work to protect and improve the Nukuhou River continues, with regional council working with farmers to develop and use nutrient management plans to identify ways to address the more diffuse nutrient leaching sources from animal urine and fertiliser use.

The Nukuhou River is the biggest tributary of Ohiwa Harbour, a place of significant ecological importance that is highly valued by locals and visitors.

The river catchment is very small, at 100sq km, and most of it is in agriculture of one sort or another.

There are 16 dairy farms, eight drystock farms and some small operations, placing significant pressure on the river's water quality.

Regional council consented dairy effluent discharges following the adoption of the Resource Management Act in the early 1990s.

It inspects all dairy sheds regularly, either annually or every three years depending on the type of effluent system and each farm's history of compliance.

Compliance levels across farms in the Bay of Plenty have generally improved over the past five years.