Lindsay Island Project
Above: Lindsay Island. Photo: Mallee CMA.
A suite of large-scale, integrated water management structures planned for Lindsay Island will inundate thousands of hectares of high-value floodplain, using minimal amounts of environmental water. This package of works is about providing highefficiency use of environmental water to deliver tangible improvements to the health of Lindsay Island. The Lindsay Island works are central to helping Victoria reduce the impact on irrigators of the Sustainable Diversion Limits set under The Basin Plan. Government support for the preliminary investigations into this suite of environmental works means that after years of scientific research, investigations and discussions with locals, this project can progress to the Business Case stage. This stage of the development process is an important progression in the rigorous assessment process that is applied to major projects.
At a glance The proposed works at Lindsay Island will make it possible to: • Deliver water to a large area of the floodplain, using substantially less water than would be required by a natural flood. • Flood areas of the Lindsay Island floodplain unable to receive water until River Murray flows reach between 90,000 and 130,000 ML/d. • Due to river regulation, floods of this magnitude occur less often and as a result flood dependent ecology has suffered (e.g. Blackbox trees).
Above: Mullaroo Creek, Lindsay Island. Photo: Mallee CMA.
Proposed works â€˘ One large environmental regulator on the Lindsay River near Berribee Homestead; â€˘ A series of smaller regulators would complement the large regulator to maximise water use efficiency and environmental benefits. These engineering works will make it possible to achieve important environmental benefits without needing major flows in the River Murray.
wet when the River Murray was flowing at between 90,000 and 130,000 ML/day. Under typical regulated conditions, River Murray flows to South Australia have been less than 15,000 ML/day. The package of works will be able to be operated to mimic a natural flood event, with the structures making it possible to hold water at strategic points on the floodplain in order to derive full ecological benefits.
Taking a holistic approach
Due to river regulation, significant flows in the River Murray have become less frequent. This has meant important areas of Lindsay Island with flood-dependent species, such as Black Box trees and lignum, have suffered.
The works proposed for Lindsay Island are part of an integrated approach to efficiently and effectively improving the environment. The planned works will complement the Stage 1 works that are due to be constructed next year.
By constructing the planned works, environmental water will be able to be delivered to parts of Lindsay Island that would only be
The proposed works are a natural continuation of the Stage 1 works funded under The Living Murray (TLM) project.
Stage 1 works include: • lowering the sills of the northern and southern Lindsay River inlets; • constructing regulators on these inlets; and • replacing the degraded causeway in the Mullaroo Creek with a new regulator and fishway. These works provide greater flexibility to manage flow regimes in the Lindsay Island watercourses and improves connectivity for fish over a wider range of (Lock 7) pool levels. Stage 1 has been funded under The Living Murray program. Work is currently progressing on detailed designs, with construction proposed for 2013.
Why choose Lindsay Island? • It is one of the most environmentallyvaluable areas of floodplain in the Victorian Mallee;
• The 15,000 ha island is formed by the River Murray to the north, between Lock 8 and Lock 6, and the Lindsay River to the south; • The Lindsay Island floodplain is relatively flat, dissected by a network of anabranches and small creeks, with areas of permanent and ephemeral wetlands. • When inundated, the waterways and wetlands of Lindsay Island provide refuge and resources for threatened flora and fauna, as well as important waterbird breeding habitat during flood events. Mullaroo Creek also runs through Lindsay Island and is a significant Murray Cod breeding ground. • Lindsay Island is part of the Chowilla Floodplain Lindsay Wallpolla Icon Site - one of six Icon Sites identified for restoration under the The Living Murray initiative. The Living Murray is a joint initiative funded by the Victorian, New South Wales, South Australian, Australian Capital Territory and the Commonwealth governments, coordinated by the Murray-Darling Basin Authority.
Above: Murray Cod caught in the Murray River. Photo:Rod Mackenzie. Published December 2012 This publication may be of assistance to you but the Mallee Catchment Management Authority refers readers to our Terms and Conditions, available from our website. Printed on 100% recycled Australian paper, made from pre- and post-consumer waste.