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The Campaspe system includes the Campaspe River and the Coliban River.
5.6.1 Campaspe River
System overview
Natural inflows in the upper Campaspe River catchment are harvested into Lake Eppalock, which is located near the townships of Axedale and Heathcote. The main tributaries of the Campaspe River are the Coliban River, McIvor and Pipers creeks above Lake Eppalock and Mount Pleasant, Forest and Axe creeks below Lake Eppalock. Below Lake Eppalock, the major in-stream structure is the Campaspe Weir, which was built to divert water to the Campaspe Irrigation District. It is no longer used for water diversion but is a barrier to fish migration. Higher flows usually spill over the weir. The Campaspe Siphon, just below Rochester, is part of the Waranga Western Channel, which carries water from the Goulburn system to western Victoria. Water can be released from the Waranga Western Channel into the lower reaches of the Campaspe River, but the siphon is another barrier to fish migration when there is low-to- moderate flow.
The flow below Lake Eppalock is largely influenced by releases from storage and the operation of the Campaspe Weir and the Campaspe Siphon. The Campaspe’s major tributary (the Coliban River) flows through the three Coliban Water storages (the Upper Coliban, Lauriston and Malmsbury reservoirs) before reaching Lake Eppalock. Water for the environment is held and released from Lake Eppalock, with some limited ability to regulate flow further downstream at the Campaspe Weir.
Water for the environment is released from Lake Eppalock to support aquatic plants and animals in and along the river. It can be supplemented by water for the environment delivered via the Waranga Western Channel at the Campaspe Siphon, which provides important flexibility to meeting reach 4 demands. Water for the environment is primarily used to improve the magnitude and variability of flows during the winter/spring. Primary flow measurement points are at Barnadown (reach 2) and below the Campaspe Siphon (reach 4).
Goulburn-Murray Water transfers operational water from Lake Eppalock or through Waranga Western Channel
to customers in the Murray River and to downstream storages (such as Lake Victoria). These IVTs usually occur in summer/autumn and, depending on the rate of delivery, can either support or compromise environmental watering objectives. High IVT flows delivered at a time when the Campaspe River would naturally have a low flow may reduce the amount of suitable habitat for juvenile fish, which rely on protected, shallow areas of water near the edge
of the river channel. Sustained high IVT flows in summer can also drown streamside vegetation. Storage managers and the CMA have been working cooperatively to enhance the positive effects and limit the negative effects of IVTs
on native plants and animals in the Campaspe River. For example, IVTs are sometimes delivered in a pattern that meets summer low flow and fresh requirements, thereby reducing demand on the environmental entitlement. IVTs have also been released in a pattern to support native
fish migration from the Murray River into reach 4 of the Campaspe River, without affecting delivery to downstream users.
Environmental values
The Campaspe River below Lake Eppalock provides important habitat for several native fish species including Murray cod, silver perch, golden perch, Murray-Darling rainbowfish and flat-headed gudgeon. Murray-Darling rainbowfish were presumed lost from the system during the Millennium drought, but since 2011, they have been recorded at many sites on the Campaspe River and are now abundant below Elmore. Environmental flows help native fish migrate and disperse throughout the Campaspe system.
Platypus, rakali (water rats), turtles and frogs are also present along the length of the Campaspe River. The streamside vegetation zone is narrow and dominated by large, mature river red gum trees that support wildlife (such as the swift parrot and squirrel glider).
5.6 Campaspe system
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