Earth:Goolwa Barrages

Short description: Series of five barrages at the River Murray mouth, South Australia

Short description: Dam in Coorong National Park, South Australia

Goolwa Barrages
A map showing the location of each of the Goolwa Barrages
Country	Australia
Location	Coorong National Park, South Australia
Coordinates
Purpose	Flood control
Status	Operational
Construction began	1935
Opening date	1940
Built by	Engineering and Water Supply Department
Owner(s)	Murray-Darling Basin Authority
Operator(s)	SA Water
Dam and spillways
Type of dam	Barrage
Impounds	River Murray
Length	various

The Goolwa Barrages comprise five tidal barrages in the channels separating Lake Alexandrina from the sea at the mouth of the River Murray, near Template:SAcity, 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 250 kilometres (160 miles) upstream from the mouth of the River Murray, approximately as far inland as the river port at present-day Swan Reach.

Goolwa Barrage looking towards Hindmarsh Island

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 2,000 kilometres (1,200 mi) 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 first Goolwa barrage

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.

Barrage name	Coordinates	Western shore	Eastern shore	Description	Notes
Goolwa	[ ⚑ ] 35°31′S 138°48′E	Sir Richard Peninsula	Hindmarsh Island	Includes a lock; measures 30.5 by 6.1 m (100 by 20 ft)
Mundoo	[ ⚑ ] 35°32′S 138°54′E	Hindmarsh Island	Mundoo Island
Boundary Creek	[ ⚑ ] 35°33′S 138°57′E	Mundoo Island	Ewe Island
Ewe Island	[ ⚑ ] 35°33′S 138°58′E	Ewe Island	Tauwitchere Island
Tauwitchere	[ ⚑ ] 35°35′S 139°00′E	Tauwitchere Island	Pelican Point	Includes a lock; measures 13.7 by 3.8 m (45 by 12 ft)

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

Note: This topic belongs to "South Australia" portal

• List of reservoirs and dams in South Australia
• List of tidal barrages