Western Distributor (Sydney)

Western Distributor is a 4.3 km grade-separated motorway that is primarily elevated for the majority of its route on the western fringe of the Sydney central business district. It links the southern end of Bradfield Highway at the Sydney Harbour Bridge to Victoria Road in Rozelle, at its western terminus near White Bay. It is a constituent part of the A4 route.

Route
It is an unusual motorway as, citybound, it heads east, southeast after the Anzac Bridge, east, north then northeast. The freeway distributes traffic arriving from the north (a function which gives the road its name) while collecting traffic from the CBD, distributing it through Pyrmont and Ultimo before crossing over the Anzac Bridge. In the citybound direction, traffic is collected from Victoria Road and the City West Link, as well as various on ramps in the Pyrmont and Ultimo areas. Traffic is distributed into the CBD through various off ramps in Pyrmont and the western edge of the CBD, as well as into the Cross City Tunnel. The remaining traffic is fed into Bradfield Highway, as it is not possible for northbound traffic to exit onto Cahill Expressway (traffic travelling east on Western Distributor wishing to reach the eastern edge of the CBD and beyond must either travel through the Cross City Tunnel or negotiate the packed streets of the CBD).

Construction of the Rozelle Interchange as part of Stage 3 of WestConnex is underway. With its completion in 2023, it will provide a freeway-standard route free of traffic lights from Sydney's CBD to its outer western suburbs and the Blue Mountains.

History
Western Distributor came to be out of the realisation in the early 1960s that the existing roads that supported the Harbour Bridge would not cope with contemporary and projected traffic volumes. Due to existing infrastructure and buildings in the area, it was decided to build a viaduct to carry traffic above the city streets. Western Distributor was opened in stages starting in September 1972, with the last stage being the Anzac Bridge which was opened in December 1995. The distributor also replaces the former congested route out of the city via the Pyrmont Bridge (closed in 1981) and the Glebe Island Bridge (closed in 1995 with the opening of Anzac Bridge).

The north-eastbound viaduct ramps leading towards Bradfield Highway, designed in 1967, was widened from 19 to 30 m to accommodate a deck with a variable width from 2.3 to 5.5 m and consists of a steel structure supported on reinforced concrete corbels.

The passing of the Main Roads Act of 1924 through the Parliament of New South Wales provided for the declaration of Main Roads, roads partially funded by the State government through the Main Roads Board (later the Department of Main Roads, and eventually Transport for NSW). With the subsequent passing of the Main Roads (Amendment) Act of 1929 to provide for additional declarations of State Highways and Trunk Roads, the Department of Main Roads (having succeeded the MRB in 1932) re-aligned the eastern end of Main Road 165 from its old route from Pyrmont, to the southern toll plaza of the Sydney Harbour Bridge at Millers Point to the interchange with Pyrmont Bridge Road and Bank Street in Pyrmont (and continuing west across Bank Street and Glebe Island Bridge to Rozelle and along Victoria Road to Parramatta) on 22 January 1993, later amended to use the Anzac Bridge instead on 28 February 2003. Despite its role as a grade-separated motorway, the road is not officially gazetted as one by Transport for NSW classification, and is still considered today to be a main road.

The passing of the Roads Act of 1993 updated road classifications and the way they could be declared within New South Wales. Under this act, Western Distributor retains its declaration as part of Main Road 165.

Western Distributor was signed State Route 40 in 1981, and followed the route's re-alignment when Anzac Bridge opened in 1995. Its eastern half was also declared part of National Route 1, when it was re-aligned from its old route through the CBD along York and Clarence Streets to its new route along Western Distributor to Harris Street (and continuing south along Harris Street to meet Princes Highway at Chippendale) in 1986, and removed when the Sydney Harbour Tunnel opened in 1992. It was quickly replaced in 1993 by Metroad 2 along the same alignment (and continuing south along Harris and Wattle Streets to terminate at Ultimo) until the Lane Cove Tunnel opened in 2007 and Metroad 2 was truncated to meet Gore Hill Freeway in Lane Cove. The whole route was also designated part of Metroad 4 when its eastern end was re-aligned on the opening of City West Link in 2000. With the conversion to the newer alphanumeric system in 2013, State Route 40 was removed and Metroad 4 was replaced by route A4.

Western end
When it was built, it was described as the southern end of the F3 Freeway, as that was where the North West Freeway was intended to finish, however due to protests from inner city residents, this plan never came to fruition. Western Distributor ends west of the Anzac Bridge western ramp and east of the junction between Victoria Road and City West Link, with traffic fed onto either of these roads.

Abandoned section
Under the Western Distributor viaduct ramps at its northern end, between Sussex and Kent streets, there is an abandoned carriageway underneath the main roadway. It is a short section of elevated freeway; the top tier remains in constant use but the lower is suspended in the air; having been severed at each end.

In popular culture
The road is referenced in the song "Hay Plain" by Australian artist Julia Jacklin.