|Historical notes: ||Sydney was declared a city in 1842 and was concentrated in the area currently occupied by the modern CBD. In the mid-1800s, it was a mix of commerce, retail, residences, manufacturing works and factories, with the Botanic Gardens and Domain to the east, port activities to the west and north and road outlets at its southern border leading to the inner western suburbs via the Parramatta Road, which was also the beginning of the Great Western Highway. By mid-century, it had become clear that a shorter route out of the city was available, across Johnstons Bay to the Glebe Island and on to Annandale.
The first Glebe Island Bridge was a private toll-bridge completed in 1862 and was a timber beam viaduct with a small, one arm, hand-cranked swing-span tucked into the Pyrmont shore. After 30 years, this bridge was in need of extensive repairs and the Colonial Government purchased the structure and the Public Works Department (PWD) began planning a replacement bridge.
The construction of the second bridge related also to a project commenced in the 1880s for the Five Bridges Route, to facilitate traffic flow from the city to the northern and western suburbs of the expanding city. Bridges were to be built or replaced at Pyrmont Bay, Glebe Island, Iron Cove, Gladesville and Fig Tree (until these bridges were built, the only access to the northern shore of the Harbour was by boat, punt or by road via Parramatta). For this project, the (old) Pyrmont Bridge and the (old) Glebe Island Bridge were purchased from their private owners and new bridges were built at Gladesville (1881), Iron Cove (1882) and Fig Tree (1885).
These completed, attention turned to replacement of the Pyrmont and Glebe Island Bridges. The Sydney Morning Herald reported in September, 1890:
"The Departmental Board appointed by the Minister for Public Works nearly a year ago to consider the desirability of constructing new bridges to replace the present Pyrmont and Glebe Island bridges ... has now furnished the Minister with a lengthy report on the subject. The Board has decided in favour of the construction of a new bridge adjoining the present Pyrmont Bridge. The structure recommended is an iron or steel superstructure on cast-iron cylinders, with a roadway 12ft, in width, and two 12ft. footpaths. ...With regard to the Glebe Island Bridge, the Board recommended the construction of a bridge close to the present one, of a character similar to the proposed Pyrmont Bridge, at a cost of (Pounds)140,000."
An international design competition for a new 'Pyrmont Bridge' was called in 1891. The Department of Public Works submitted a non-conforming design based upon a much larger bridge than specified in the design brief.
Prizes were awarded but no designs were selected and the proposal was deferred, largely owing to the economic downturn of the early 1890s but also owing to different opinions regarding the best approach. The Chief Engineer for Harbour and Rivers, C W Darley, favoured the construction of a new bridge - the Chief Engineer for Roads and Bridges, Robert Hickson, favoured the reclamation of Darling Harbour as far north as Bathurst Street and no replacement for the Pyrmont Bridge at all.
In 1894, the proposal was referred to the Parliamentary Standing Committee for Public Works (the Public Works Committee) and, reporting in June, the Committee favoured no particular scheme but recommended that, when renewal of Pyrmont and Glebe Island bridges became advisable, they should be replaced by timber structures.
On November 21, 1894, the Public Works Committee (reformed in the interim under a new government) recommended that Pyrmont Bridge be replaced by a timber bridge with steel swing-span, to cost (Pounds)82,500, and that Glebe Island Bridge did not require renewal. No funds were allocated, though and no action resulted. By 1897, however, the Committee had reconsidered its stance and recommended the replacement of the old Glebe Island Bridge with a stone causeway and a bridge with a steel swing-span, at a cost of (Pounds)89,100. Parliament voted the funding for these works in 1898 and detailed design work commenced in the Public Works Drawing Offices.
Design of the bridges was led by Percy Allan, who had been appointed Engineer-in-Chief for bridge design in 1896. His assistant engineer was E.M. De Burgh and the junior engineers were H H Dare, J J Bradfield and J W Roberts, all of whom went on to have distinguished careers in public works engineering. Bradfield had charge of the the team responsible for the substructure, foundations, abutments and retaining walls for both bridges. Tenders for the construction of both bridges (separate contracts) were invited in March, 1899.
For both sites, Allan designed an electrically-operated swing bridge, the earliest use of electrical power for this purpose in Australia. The bridges were considered very innovative at the time of their construction and attracted international attention. For the Glebe Island Bridge, the large pivot pier was founded on a nest of timber piles capped by concrete, whereas the Pyrmont pivot pier was founded on rock.
Construction commenced on the Glebe Island Bridge and Pyrmont Bridge at the same time but Glebe Island involved more extensive (and time-consuming) land resumptions, extensive waterfront reclamation and the construction of an elevated causeway across Glebe Island. Over 100,00 tons of mud was dredged to establish the causeway and the fill was obtained by cutting down what was left of the hillock of Glebe Island, producing 5.3 hectares (thirteen acres) of flat land for railway yards and 853 metres (2,800 feet) of deepwater frontage for wharfage. In August, 1899, a large load of ballast being placed for the causeway to the new bridge slipped sideways and crushed the piles of the old bridge, rendering it unfit for anything but pedestrian traffic for the following two weeks.
Construction of the trussed swing spans at each site was by simple cantilevering out from the steel pivot ring. Where timber trusses were used for the approaches of the Pyrmont Bridge, the Glebe Island Bridge used two steel deck trusses, then stone-faced embankments to reach each shore. The use of steel trusses for the approach spans had been part of Allan's original design for the Pyrmont Bridge but the Parliamentary Standing Committee on Public Works directed that this material be replaced with timber, presumably as a cost-cutting measure. When Glebe Island Bridge was built, Allan's original specification was reinstated (perhaps owing to the use of built-up embankments and shorter approach spans, providing a more economical outcome).
The contractor for construction was H McKenzie and Sons and the bridge was opened on 1 July 1903 by Miss Lily See, daughter of Premier, Sir John See.
The Glebe Island Bridge operated from 1903 to 1995 with little interruption and few major works, apart from maintenance, being undertaken. In 1933, the bridge underwent an underwater upgrade, with underpinning to replace decayed piles around the central pier. In 1961, the DC electricity supply from the Tramways system was shut down, as was the tramway system in Sydney. A new AC supply was obtained from the local reticulated network and a set of rectifiers was installed in a small kiosk erected on the north east side of the bridge. In the 1980s, the Control Cabin was burnt out and was subsequently rebuilt to the original design. (NT 2012)
In 1995 the bridge was decommissioned being made redundant with opening of the Anzac Bridge.