The Goolwa Barrages comprise five tidal barrages in the channels separating Lake Alexandrina from the sea at the mouth of the River Murray, near , in the Coorong National Park, in South Australia. They were constructed principally to reduce salinity levels in the lower reaches of the River Murray, Lake Alexandrina and Lake Albert, but also to stabilise the river level, for both upstream irrigation and pumping.
History Prior to the construction of the barrages, during periods of low river flow, tidal effects and the intrusion of seawater were felt up to upstream from the mouth of the River Murray, approximately as far inland as the river port at present-day Swan Reach.Murray Darling Basin Commission, "" Retrieved 17 November 2012
From the 1900s, with the advent of large irrigation schemes, landowners along the lower reaches of the river strongly urged for the construction of barrages, primarily to keep the water fresh in the lower reaches of the River Murray, as well as Lake Albert and Lake Alexandrina.
In 1931, the Murray-Darling Basin Commission authorised the construction of five barrages. Work commenced in 1935 and was completed in 1940. South Australia's Engineering and Water Supply Department undertook the project, with costs shared equally by the governments of South Australia, Victoria, New South Wales and the Australian government.
Marine passage In 2001, the Murray-Darling Basin Commission initiated a program to improve the movement of fish along of the River Murray, from the mouth to the Hume Dam. Five fishways were constructed in the Goolwa Barrages in 2002 to allow fish to migrate between saline and freshwater environments. A rock ramp fishway and two vertical slot fishways were constructed at the Tauwitchere Barrage and vertical slot fishways were built at the Goolwa Barrage and Hunters Creek. The fishways also allow freshwater species that inadvertently get washed into the estuary to return to the freshwaters of the lakes.
Description
The system consists of five barrages extending from Sir Richard Peninsula in the west to Pelican Point on the northern side of the mouth of the Coorong in the east, crossing five channels between the mainland and three islands. From west to east, the five barrages are named Goolwa, Mundoo, Boundary Creek, Ewe Island and Tauwitchere.
Coordinates Western shore Eastern shore Description Notes Goolwa Includes a lock; measures Mundoo Hindmarsh Island Mundoo Island Mundoo Island Ewe Island Ewe Island Ewe Island Tauwitchere Tauwitchere Island Pelican Point Includes a lock; measures
Engineering heritage award The barrages are listed as a National Engineering Landmark by Engineers Australia as part of its Engineering Heritage Recognition Program.
See also
List of reservoirs and dams in South Australia List of tidal barrages
References