Work underway to protect KI's waterways

As attention turns from emergency relief to the long-term recovery of KI, Natural Resources Kangaroo Island (NRKI) has begun a new project, working with landholders to reduce the risks of water contamination in farm dams and priority water courses.

The bushfires on KI left a lot of loose nutrient-rich ash and sediment laying on the ground with little vegetation to help reduce erosion and rapid run-off of water. The fires have also left little shade for our streams and rivers, leading to raised water temperatures that increases algae growth. 

This new project, the Protection of Water and Soil Resources Project, is jointly funded through the state NRM Fund and the Australian Government’s National Landcare Program and will work with volunteer groups to deliver assistance to landholders and protect farm dams and priority watercourses.

 

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sediment-laden run-off following the heavy rains in Feb

Andrew Heinrich, Presiding Member of the new KI Landscape Board, says that the heavy rains in late January led to a lot of ash and charcoal being washed into dams and water courses.

“After the heavy rains there were several reports from around the island of water black with ash and charcoal being washed into dams and water courses, leading to fish deaths and some growth of toxic blue-green algae,” said Mr Heinrich. 

“NRKI are taking action, with the welcome aid of volunteer groups such as All Hands and Hearts and Rubicon, to help landholders control sediment run-off to prevent selected farm dams and water courses being contaminated.”

“There is expected to be large amounts of erosion, siltation and contamination of dams and watercourses in the untreated areas, so the help from volunteers is extremely welcome.”

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The high levels of nutrient-rich sediment in the river led to oxygen-deprived environment which led to fish deaths

Mark Agnew, Water Management Officer at NRKI, said that once sediment and ash has washed into a dam or waterbody there is no effective way to manage the impact, so steps must be taken now to minimise sediment run-off and mitigate erosion risk. 

“We are using a number of tools, including locally sourced straw bales, coir logs and geotextiles to trap sediment and reduce erosion risk”, said Mr Agnew. 

“Our immediate focus is on areas that were severely burnt and that have a high water erosion potential, and of course where landholders have asked for assistance.” 

“The aim is to protect important assets that are at risk such as farm dams and catchment water courses. We have also been working with SA Water to reduce the risk to water resources in the Middle River Catchment”

 

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The installation of coir log and straw bale barriers to help filter runoff: Mark Agnew, water management officer at NRKI with a volunteer from All Hands and Hearts

Volunteer group, All Hands and Hearts have been crucial in delivering the work with NRKI to date. David Eisenbaum, All Hands and Hearts’ Director of International Response, said that they are glad to have helped make a positive impact on livelihoods and the environment on Kangaroo Island.

“All Hands and Hearts are happy to have partnered with the KI Landscape Board to make an impact on the ground and assist those affected by the bushfires”, said David Eisenbaum.

“We look forward to continued partnership in the coming months when we resume our volunteer work on KI.”

If you would like to volunteer for this project or have a water course on your property (including small creeks and dams) that could benefit from sediment trapping, please contact Natural Resources Kangaroo Island on 8553 4444 or email kinrc@sa.gov.au .

 

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