Landowner commitment to reducing sediment input and improving water quality in the Wharekawa and Waitekuri catchments is being rewarded.
The two Coromandel Peninsula catchments have been selected by Waikato Regional Council as ‘focus catchments’ to showcase best practice works.
“We’re doing some pretty cool work in catchments to keep soil on the land and improve water quality,” said catchment management team leader Aniwa Tawa, from the council’s Whitianga office.
Reducing soil erosion enables land to remain productive over the long term and significantly reduces the levels of sediment entering our waterways, particularly during heavy rain.
“Sediment can have a major impact on water quality. It smothers the habitat of our fish and aquatic organisms and reduces the oxygen levels essential to their survival. Sediment also infills the channels which can magnify the impacts of flooding.”
She said there were a number of ways to reduce sediment input to waterways. These include riparian planting to stabilise stream banks, soil conservation planting on hill country, and fencing to exclude stock from vulnerable areas such as stream banks and wetlands.
But what’s really important is targeting the right areas to do this work, and a tool developed by regional council scientists last year helps to identify where erosion is likely to occur and what type of erosion it will be.
The tool brings together data on land erosion potential in order to identify the catchments most at risk. This is then used by council catchment management staff to prioritise soil conservation works and work with landowners to ensure their land remains productive.
On the Coromandel Peninsula the Wharekawa and Waitekuri catchments have been chosen based on the risk to water quality, opportunity to improve biodiversity, community support and accessibility.
’Ground truthing’ along river margins and other natural features in the two catchments has either been completed or is underway.
“We’ve had a glowing report on the Wharekawa catchment following our recent ground truthing. About 75 per cent of all the waterways have already been fenced to exclude stock, which shows the fantastic commitment landowners have made to doing the right thing. We know Waitekuri is likely to have a high percentage too.
“Some of the landowners have achieved this with our help, but there are many others who have completed this good work off their own back.
“There’s still more that can be done, and we’ll be talking to landowners and the communities about that in the weeks ahead,” Ms Tawa said.