Improving and developing the Collie River is an important priority for the Shire of Collie.
The Shire, guided by the Weeds and Waterway Advisory Committee, is implementing strategies to improve the health and amenity of the river and its tributaries, including the treatment of Nardoo, control of nutrients and public education.
The Shire’s Nardoo Treatment Program using Reglone over a number of years has successfully brought the weed under control. Nardoo is an introduced weed that slowed the flow of the river, was unsightly and prevented the river from being used to its full potential. A partnership between the Shire of Collie and the University of Western Australia investigated various methods to control Nardoo, including herbicides, plastic solarisation, mechanical excavation, mechanical harvesting and the use of a grappling hook. Success was achieved through the development and use of a compound herbicide, Reglone, over a number of years.
The control of nutrients being washed into the river is an important step in preventing conditions favourable for the growth of Nardoo and many other river weeds. These nutrients are mainly from fertilisers used on gardens and reserves. The Shire is implementing a number of solutions to reduce nutrient levels, including riffles to oxygenate the water, control of nutrients used on Shire land, planting trees to shade the river, increasing the depth of water using Venn Street Boards and the construction of nutrient stripping basins at inlet point.
The work carried out so far has improved the health and aesthetic of the Collie River, but there is still more to be done and the community has an essential part to play to control nutrients running into the river.
Tips for a river friendly garden include planting a native garden, the use of compost, and knowing how much, what type, and when to fertilise.
For more information, contact the Shire of Collie on 9734 9000.