Stop North East Link Alliance

North East Link noise threatens human health

The North East Link (NEL) will be a freeway-standard road linking the Metropolitan Ring Road (M80) in Greensborough to the Eastern Freeway at Bulleen Road. It will also include a significant expansion of the Eastern Freeway. At this stage, the NEL Project (NELP) remains a reference design or technical blueprint that will be subject to further design refinement wherever considered necessary.

The Project continues to be controversial and has attracted criticism from community and business interests, local government and transport planning experts. Opposition covers its environmental, social, commercial and economic impacts and the unsubstantiated claims of the benefits it will deliver.

One question concerning many residents is how the level of day and night time road traffic noise will be controlled and moderated. Already, many homes and buildings along the Eastern Freeway have had to install double glazed windows to reduce existing noise levels.

Noise is a health hazard

Noise can be annoying or disturbing. Over time, continuous loud noise can impact health and wellbeing, especially when sleep is disrupted. The World Health Organisation has reported that night noise above 55 decibels is likely to cause adverse health effects, including cardiovascular disease. According to Victoria’s Environment Protection Agency ongoing noise can also cause headaches, increased blood pressure, fatigue, irritability, poorer reading comprehension and attention in children, and hearing damage if the noise is loud.

Proposed noise level limitations

The Government has adopted a set of objectives for maximum day and night time noise levels they consider to be both achievable and sufficient to protect human health. The objective for daytime noise on all parts of the project is no more than 63 decibels. The initial objective for night-time noise of 55 decibels was subsequently increased to 58 decibels. Authorities claim these noise objectives are based on comprehensive information collection and modelling that mapped existing noise and future conditions.

Are these noise level objectives achievable and sufficient?

Critics have cast doubts on the process by which these objectives were identified and their adequacy to protect human health.

Information on the noise near overpasses and ramps and other known high noise locations was not collected. Nor was information on aggravating factors such as downwind noise and increased noise at the upper level of building structures measured. Data from the NELP Environment Effects Statement (EES) which identified that 155 properties at different parts of the project would experience noise exceeding 63 decibels, appears not to have been acknowledged. Scoping Requirements for the EES, particularly for night-time noise, referred to the 2009 World Health Organisation (WHO) document, which recommends 40 decibels for night-time at the upper level of a building. This appears not to have influenced the collection of information. Nor, apparently, has the NSW Policy, which sets noise levels for night-time at 50 decibels for new roads and 55 decibels for existing roads, both at the upper level of a building.

Are these objectives fit for the long term?

Authorities should be aware that associated road traffic noise may increase over time. The matter was discussed in 2019 at the North East Link Project Inquiry and Advisory Committee (IAC) meetings.

One IAC meeting report questioned whether ‘… the quoted diurnal difference which has been estimated from actual measurements to date will hold true in the long term, especially as the Project is espoused to be a major freight route.’ The report pointed to the likelihood that freight trucks ‘… could potentially be drawn to the Project during non-peak times during the night. If traffic volumes during night-time periods are substantially different from existing traffic levels, then the anticipated decrease in night-time noise levels may not occur.’

The claim that most properties would be protected by upgrading existing noise walls, building new high-quality noise walls and applying other approaches such as low-noise road surfaces should also be challenged.

Open grade low noise asphalt already exists on the Eastern Freeway and will not contribute to any further improvements. Current advice is that vertical concrete wall systems, that do little to absorb noise, will continue to be used in preference to best practice solutions such as Swiss acoustic noise walls.

Barry Watson

Eastsider News June 2023