Environment Considerations for the Hunter Expressway
Tuesday, 25 March 2014
The Hunter Expressway is expected to be opened about the same time that you receive this newsletter. This is a 40 kilometre road linking Seahampton to Branxton and was built to strict environment standards aimed at minimising the project's impact on the environment.
There has been much work done for this new expressway. Three bridge viaducts have been built across deep valleys on the Sugarloaf Range plus ten other bridge structures, eight culvert underpasses and eight arboreal crossings which will provide habitat connectivity and reduce road kill. Meanwhile consideration was given to water based fauna.
Before construction began an ecologist did a pre-clearing survey to identify the fauna and potential habitat trees. The ecologist then supervised the clearing allowing the fauna to escape the areas before the habitat trees were removed. Any uninjured fauna that were present after clearing, were relocated while those that were injured were taken to wildlife rescue services for recovery. Nest boxes were installed to replace tree hollows that would be destroyed, while coarse debris (logs and bush rock) were relocated outside the footprint of the project. Exclusion fencing was installed along the length of the expressway to funnel native wildlife to the underpasses to reduce road kill.
One of the nesting boxes
Adjacent areas to the project were rehabilitated with native vegetation and over 300,000 plants were planted. Many of these plants were grown from the native seed collected or the seeds were scattered. The topsoil had been collected and stored in units of soil type during construction which enabled plants to be planted in specific areas..
Meanwhile, it was necessary to protect the water quality, of the area. Eighty nine water quality basins were installed during construction and a further eight will be operational when the project opens. Sediment basins were used to collect run-off during construction. Water collected was stored and treated before being released to the water ways. Care was taken to allow a buffer zone at the bridges, so that the riparian vegetation could be retained or rehabilitated.
Culvert construction at Black Waterholes Creek
There was, also, Aboriginal cultural heritage in the area and local Aboriginal communities were involved during the early surveys and investigations, as well during the project. In fact, the site was one of the largest subsurface archaeological investigations that have been carried out in Australia.
Those living near the expressway could have had problems with noise both during construction and after the project is utilised. Noise walls were built along the alignment where the road went close to residential areas. These walls had their visual impact reduced by landscaping, using various textures and different colours while at the same time discouraging vandalism. 'At resident' noise treatment was provided to properties would have had excessive noise levels. This 'at resident' treatment could include the installation of air-conditioning, re-glazing windows, replacing seals around doors or windows and replacing external doors with solid timber. A low noise surface (Stone Mastic Asphalt) was also used some areas.
The design and location of the alignment was selected carefully to utilise previously clear land and minimise any other clearing.
As the expressway is shorted it should reduce the amount of fuel used by transport but in all probability more people will be using the link as it will reduce the time to get to many points in the area.