Garden Memorial Wall

for the Royal Botanic Gardens and the Domain

Inside the Domain The Domain from the Cahill Expressway
The previous situation

Click here to view media release 1 August 2005

Click here to view Frequently Asked Questions about Noise Protection Walls

Click here to view Community Consultation Comments

Click here to view Summary of Responses to Community Consultation

Click here to view Market Research Consultation Results (pdf file 2MB)

Click here to download the Audio Report (large PDF file 5 MB)

The Domain was separated from the Royal Botanic Gardens more than 40 years ago when the Cahill Expressway was constructed. Traffic volume using the Cahill Expressway has increased to the level that traffic noise in some parts of the Domain and Royal Botanic Gardens is now double the EPA goal for passive recreation land. The Cross City Tunnel will link with the Cahill Express way when it opens in 2005. One of the conditions of approval for the Cross City Tunnel was that traffic noise and its visual impacts in the Royal Botanic Gardens and the Domain be mitigated. Some time ago the Trust suggested building sound barriers along both sides of the Cahill Expressway that would reduce noise. Based on feedback from stakeholder meetings late in 2004, four options (including not building a wall on the Domain side) were tested during February and March in focus groups, on-site interviews, web-based surveys and Friends’ questionnaires.

The decision has been made to erect sound barriers on both sides of the Cahill Expressway: a higher timber fence to replace the one beside the service road on the Royal Botanic Gardens side (with a transparent section on the existing picket fence at the western end), and a sandstone-lined concrete wall on the Domain side.

The Premier has announced that the Domain garden wall will be a memorial to Australian servicemen and women who have died overseas while on non-combatant duty.

The Domain Master Plan recommends the Botanic Gardens Trust (BGT):

'Mitigate, where possible, the intrusive effect of the Cahill Expressway to the north of the Phillip Precinct by improving the legibility of the edges and entrances to the Domain through bold boundary plantings and redefining edges with appropriate hard details in order to retain – and in some cases recover – the integrity of its spatial and scenic qualities. New structures should be of a contemporary design to an exemplary standard using quality materials with a view to generally being visually subservient within the relevant landscape context.'

If you would like more detailed information see the Domain Masterplan, Volume 2, sections 8.2.2.B.5, 8.2.3.C.1, 8.2.6.F.3 and 8.2.7.K7.

Construction methods and materials investigated were earthen mounds, tree plantings and masonry and transparent walls.

Constraints on site are underground utilities, easements, heritage issues, park and garden usage patterns and aesthetics.

Consultation with engineers, designers and stakeholders resulted in four options to achieve a quieter environment at the Royal Botanic Gardens and Domain, they were:

A transparent wall 2.5 m high along most of the border between the Domain and the Cahill Expressway. This option would mitigate noise but not the view of traffic from the Domain. On the Royal Botanic Gardens border with the Cahill Expressway transparent panels to the height of the steel picket fence and an increase in height of the existing timber fence beside the Depot access road from 2 m to 4 m.
A sandstone-faced concrete wall 2.5 m high along most of the border between the Domain and the Cahill Expressway to reflect the sandstone of the NSW State Library and the NSW Art Gallery, partially screened by existing and additional plants and linked centrally by a transparent wall. This option would reduce noise and allow motorists on the expressway a partial view of the Domain. The extension and modifications of the Royal Botanic Gardens fence would be the same as in option 1.
A sandstone-faced concrete wall 2.5 m high bordering most of the Cahill Expressway from the NSW State Library to the NSW Art Gallery, partially screened by existing and additional plants. The extension and modifications of the Royal Botanic Gardens fence would be the same as in option 1. These options would reduce both traffic noise and visuals.
No noise protection for the Domain. The extension and modifications of the Royal Botanic Gardens fence would be the same as in option 1.

Benefits to the community include:

Pedestrians and visitors in the Domain and the Royal Botanic Gardens will experience a reduction in noise generated by the Cahill Expressway, closer to EPA goals for passive recreation land. We estimate that perceived sound levels will be reduced by approximately a quarter (5 dB) in the area near to the expressway (see the audio report for further information).
Sandstone facing on the Domain side will be sympathetic to the heritage precinct.
The tree canopy between the Domain and Botanic Gardens will be the dominant focus rather than high volumes of traffic. The new plantings of Port Jackson Figs and Cotton Palms in the Cahill Expressway median will add to the canopy as they too rise further above the height of the walls.
Passing motorists will see evergreen climbers on the sandstone option and the tree canopy above.
One of Sydney’s busiest city pedestrian thoroughfares, the Domain, will reclaim its parkland serenity and visitors to the Royal Botanic Gardens will enjoy a more tranquil experience.

Click here to see the poster on public display in the Domain and the Royal Botanic Gardens (pdf file 2 MB). Note that closing date for submission has now past, and a decision has been made (see above).