Following the acceptance of the tender…..work on the construction of the Hawkesbury River-Mt White section of Sydney-Newcastle Expressway commenced on 23 April, 1963.

Existing Road

The Pacific Highway between Hornsby and Gosford was constructed by the Hornsby Shire Council and Main Roads Board between 1925 and 1930. Whilst the grades of the existing road are easy, the maximum being 5%, there are over 200 curves between Cowan and Gosford.

Investigations for the new route

Due to the rugged country through which the current route passes, major improvements would involve substantial earthwork, mainly through sandstone, and still wouldn’t provide an alignment allowing higher speeds. It was also evident that, for the most part, widening of the existing road to provide a width to accommodate four lanes wouldn’t be a satisfactory solution. An investigation by the Department of Main Roads was done to establish a route for the new road. In the meantime, climbing lanes have been added where practicable.

The object of the investigation was to find a line at acceptable costs to give comfortable travel at a minimum of 50 miles per hour. In addition, it was considered essential that the road should be a true expressway, or in other words, there should be no frontage access from abutting properties, all intersecting roads should be carried over or under the expressway, and all interchanges where the expressway connects to the local road system should be designed to provide for traffic to join and leave the expressway with safety at a reasonable speed.

The investigation covered the route of a road of expressway standard southward to link with the expressway system included in the County of Cumberland Planning Scheme and north to Swansea to join the planned expressway between Swansea and Newcastle included in the Northumberland Planning Scheme.

Other factors which it was necessary to take into consideration in the investigation were:-

1. The retention of any existing assets suitable for incorporation in the expressway such as the existing bridge over the Hawkesbury River

2. The reduction to a minimum of interference with developed property, particularly houses and orchards and other intensely cultivated land. For this reason it was desirable that the route should skirt and not pass through settled areas

3. In view of the high total cost, the desirability of selecting a location which would permit stage construction and allow the road to be brought into use progressively, stage by stage

4. The need to give priority in construction to the length between the Hornsby area and Gosford for the reason that this length carries more traffic than north of Gosford and it also embraces the sections of the existing which prevent the more difficult driving conditions

5. The need of a high standard connection to serve the north and north-western parts of the state passing to the west of Newcastle and linking with the existing New England Highway in the vicinity of Singleton. This link would also serve the coalfields area, centred on Cessnock.

Invitation of offers to build expressway

Prior to a firm conclusion on the general route being reached, offers were invited in Australia and overseas for the financing, construction and operation of a toll road to expressway standards between the Sydney and Newcastle areas. No route was specified but the route [Wahroonga-Peat’s Ferry-Peats Ridge-Ourimbah-E of Wyong-Swansea] was included in the info made available by the Department. The route [Pymble-Terey Hills-Juno Point-Mooney Gorge-Somersby] was included as a possible alternative.

Three offers were received but none were accepted. Instead, the government, in January 1962, decided to adopt a proposal by the Department of Main Roads for the construction of an expressway along the route [via Peats Ridge.]

Construction of further sections

It is expected that the whole length between the Hawkesbury River and Calga will be completed within a period of four years from March 1963.

After construction of the Hawkesbury River-Calga length, the next major section will be the length from the Hawkesbury River to Wahroonga.

Ultimately it is likely that the route of the expressway between Calga and Ourimbah will be [Calga-Mooney Gorge-Kariong-Ourimbah]. Construction along the route will involve the building of a bridge over Mooney Creek at the cost of about £3,000,000. However, the route through Peat’s Ridge will need to be used for some years before the construction of the alternative route will be economically practicable.

In the meantime, the two-lane road being built to expressway standards between Peat’s Ridge and Ourimbah will be completed in December 1963, and this, with the existing road between Calga and Peat’s Ridge, will enable traffic proceeding to Ourimbah and beyond to divert from the Pacific Highway and avoid the winding section of the highway into Mooney Creek and the closely settled area from Gosford to Ourimbah.