Reverse Amenity Assessments – Assessing the Potential for Development

What is a Reverse Amenity Assessment?

Most people are familiar with impact assessments, such as Environmental Impact Statements (EIS), which are required when a significant new project is proposed. The objective of an impact assessment is to understand how the proposed development is likely to affect the existing environmental values of the project site and surrounds.

The objective of a reverse amenity assessment, however, is not to assess the impact of the proposed project on the existing environment, but to analyse how the existing environment and industry could affect the project. This is where the term ‘reverse’ comes in – it reverses the direction of the impact under consideration: from the new development impacting on existing activities, to existing activities impacting on the new development.

Reverse amenity assessments are normally required when the proposed development itself will introduce to the area new sensitive locations (which include houses) that could be impacted upon by existing activities – most often odour, dust or noise sources. If residents moving to the new development site find that there are substantial impacts then it is very likely that there will be ongoing problems of annoyance and complaints. This can ultimately affect people’s happiness and health, and generally degrade their enjoyment of their property.

Reverse amenity assessments can be completed for new residential developments, hospitals, nursing homes and childcare centres, if the development site is near an industrial, agricultural or commercial operation.

Why Would a Reverse Amenity Assessment be Required?

With Australia’s population increasing, residential developments are moving towards areas that previously were only used for industry or agriculture, creating pressures that were not previously there, and making reverse amenity assessments a necessity. Existing industrial facilities are likely to have licence conditions limiting their impacts on the environment but often those conditions do not assume that there is a highly sensitive environment on the doorstep.

Therefore the operator of a lawful use may not be required to adjust their operation as long as the licence conditions are still met. An absence of complaints is often an implied tick of compliance. The onus is on the proponent to show that the existing facility will not impact their development. If there is a risk of adverse impacts then that would also indicate a risk of complaints. If regular complaints were to occur, the existing operation might become pressured to make expensive changes, or even close down.

Licence conditions vary from one facility to another. One facility may have a blanket condition stating that it should have no negative impacts outside the boundary of the facility, while another may be required to have no adverse impact on nearby sensitive locations. These apparently small differences can be highly significant for the operations.

An Example

An example of a typical reverse amenity assessment is when a residential estate is proposed near an existing poultry farm (Figure 1).

For most existing farms with suitable buffers, dust and odour do not significantly affect existing sensitive locations. However, if a new development, such as a residential development, is built inside the buffer distance, there is a risk of nuisance impacts. In order to protect the health and comfortable lifestyle of any prospective residents, the proponent may need to demonstrate the farm’s odour impacts on the development site.

Figure 2 shows an example in which the reverse amenity assessment does show potential impacts on the proposed development. However, by modifying the development plan, the risk of impacts on the proposed development can be reduced to an acceptable level, as shown in Figure 3.

Figure 1
Figure 1: Proposed Residential Estate near Existing Poultry Farm

Figure 2
Figure 2: Result of Reverse Amenity Assessment – Proposed Development Likely to be Adversely Impacted by Poultry Farm on the Western Side

Figure 3
Figure 3: Revised Development Plan – Proposed Development Modified to Remain Outside the Buffer and Reduce the Risk of Adverse Impacts to an Acceptable Level

How is a Reverse Amenity Assessment Completed?

Reverse amenity assessments are completed in a similar manner to standard impact assessments. In the case of odour or dust, either a fixed buffer type approach is used, or the emissions from the existing industrial operations are estimated, and an appropriate dispersion model is used to predict the resulting airborne concentrations at sensitive receptors. The assessment must be completed by the proponent, so information on the existing sources may be hard to obtain, given that the existing operation is unlikely to want closer neighbours. This can make the process of estimating emissions and dispersion modelling difficult, because these processes need site-specific data. The key challenge is therefore to adequately characterise the existing operations when important information is unavailable. An experienced consultant is very important at this point.

The main technical objective of a reverse amenity assessment is to predict whether and by how much the proposed development will be affected by existing activities. Model results are relied upon to help fine tune the proposal if at first there are potential issues. Ultimately, the proposal is only likely to be approved if you can show an absence of impact on amenity.

The interpretation of model results is a vital component of the assessment. It is important that the modelling is able to show expected impacts at all parts of the subject site, including elevated locations if the development is high-rise, and under all of the situations that might occur in terms of weather and activities. Suitable modelling tools and expert evaluation of both the model inputs and outputs are vital to obtaining reliable results and conclusions, especially in more complex situations.

What is the Benefit of a Reverse Amenity Assessment?

There is an increasing need to assess reverse amenity, driven by regulators’ concerns about poorly planned developments that encroach too far into buffers designed for the mutual protection of existing activities and surrounding communities.

Reverse amenity assessments are potentially critical to an approval, and they must be done reliably by a suitably expert team.

Ensuring that potential amenity issues are dealt with before an application is lodged can greatly increase the likelihood of approval and reduce the process time.

How Pacific Environment Can Help

Pacific Environment’s team of internationally recognised specialists has completed amenity and reverse amenity assessments for a wide range of existing agricultural, commercial and industrial operations, in both rural and urban applications. Our team has the experience and expertise to prepare an assessment that is robust, reliable and timely.

Want to find out more? Contact us