Patawalonga River

The first advocate for damming the Patawalonga was Thomas King MP, who introduced a Bill into the State Parliament to enable the Corporation of Glenelg to construct such a dam in 1876. Damming, apart from enabling the Patawalonga to be navigable and thus a safe harbour for yachts and other recreational watercraft, was seen as a means of reducing or removing the odour from the estuary of the river. The dam was ultimately constructed in around 1885. King's service to his community is commemorated by a street and formerly by a bridge over the river connecting Glenelg North with Glenelg. The original King Street Bridge, built in 1951, was found to be affected by concrete cancer in the late 1990s and was replaced by a new bridge in 2011, and renamed the "Michael Herbert Bridge".[4][5][6]

The weir has not precluded the need to continually dredge the outlet for boating craft to pass. A disagreement between the State Government and ferry operator Australian Ferries over the frequency dredging of sand and seaweed at the Patawalonga entrance led to the cancellation of the high-speed ferry service (featuring the Superflyte and, later, Enigma III vessels) between Glenelg and Kangaroo Island and Edithburgh on the Yorke Peninsula. The service had operated during summers from 1994 to November 2007.[7][8]

The odour of the Patawalonga has been a recurring problem ever since European settlement since the mid-19th century. It arises from seaweed that grows in the shallow depths of the river estuary and, in more recent times, due to stormwater pollution. Dredging of the outlet beyond the weir to remove sand and seaweed build-up would at times cause the seaweed to float back to shore and rot on the beach, causing a stench.[9]

Also, if too much fresh water flows into the Patawalonga it can kill off saltwater species of fish that exist in the lake.[10][11] An event like this occurred on the weekend of 22–23 January 2005; the front page of the Adelaide Advertiser reported that "Residents woke yesterday to an 'awful' stench and the sight of hundreds of seagulls converging on the area in a feeding frenzy."[12]

From the 1970s onwards, increasing levels of rubbish and dirty stormwater would collect in front of the weir in the Patawalonga, bringing the stench and unsightly view of debris in the water at Glenelg North. The debris and pollution had rendered the Patawalonga unusable for recreational activities such as swimming, water skiing, sailboarding and dragon boat racing, and local authorities closed the Patawalonga for such activities in 1987 due to concerns about public health due.[13][14]

Then Premier Dean Brown commissioned a review in 1995 and the then Environment Minister David Wotton promised to swim in the Patawalonga with the Premier within a year, as this was the estimated time-frame for cleaning up "the Pat".[15]

Six years later, in December 2001 the Barcoo Outlet was completed. The Outlet's intention was primarily to enable dirty stormwater from the catchment to be diverted away from the Patawonga Lake at an ultimate cost of approximately A$30m. The Outlet consists of an 885-metre (2,904 ft) pipeline diverting stormwater out of the final length of the Patawalonga and out to sea. Symbolically, the then Premier John Olsen took a media-attended swim in the Patawalonga as the State Government lifted the ban on recreational use.[15][14]

The Outlet project was initially dogged with controversy, due to failures to handle stormwater and pollution of Adelaide's beaches. People north of the Outlet (which itself is 500m north of the Patawalonga's natural mouth) at West Beach complained that the coastal drift was seeing the pollution simply shifted to their beaches instead of into the Patawalonga Lake. The Outlet also failed to handle stormwater during heavy rainfall and the resulting in stormwater pollution entered the lake section of the Patawalonga in April (2x),[16][17] May[18] and August 2002.[19] Another failure in the Outlet in February 2003 resulted in minor flooding and consequent damage to homes in both Glenelg North and upstream Novar Gardens.[20]

The lower section of the Patawalonga at Glenelg North is now more-or less operated as a lake, with seawater at times circulated in through the river mouth and then out through the Barcoo Outlet to the north. The Outlet is named after the frigate HMAS Barcoo, which ran aground at Glenelg North during a violent storm on 11 April 1948, which also destroyed most of the jetty at Glenelg.

The Patawalonga weir

Heavy rainfall and a malfunction in the weir resulted in the Patawalonga breaking its banks at Glenelg North on Friday, 27 June 2003 and flooding the homes of local residents.[21] The situation became a major political issue with the Premier, Mike Rann, declaring that he would establish a compensation fund for victims who had suffered water damage to their homes. A local newspaper report suggested that 160 homes were affected and the cause of the flooding was the gates to the weir being kept closed during a stormwater flood to protect yachts harboured in the Patawalonga Lake.[22] 145 residents made 150 claims upon the fund and at least A$1.4m was paid to the victims, ultimately, by weir operator Baulderstone Hornibrook.[23] A class action was later launched by 70 residents for further compensation for 'stress and inconvenience'.[24]

A replica of HMS Buffalo is permanently moored on the Patawalonga. The original Buffalo had made a six-month voyage carrying the first 400 settlers to South Australia in 1836. It had also carried Captain Hindmarsh, captain of that vessel and, upon his arrival, the first Governor of South Australia. The Buffalo replica has served[34][35] as a family and a la carte restaurant floating on the Patawalonga.[36]