Arboricultural Impact Assessments

Getting a Planning Permit: Constructing Near Trees

When constructing near trees, it is important to consider the potential impact that the construction may have on the trees. Trees are a valuable asset to any property, providing shade, aesthetic beauty, and environmental benefits such as reducing the heat island effect and improving air quality. However, they can also cause structural damage or be damaged if not properly accounted for during the construction process. This is why many councils now require tree reports and impact assessments as part of the planning permit process.

Why Councils Now Require Tree Reports

Councils require impact assessments to ensure that trees are properly protected during construction and that any potential damage is minimized. Trees are often an integral part of a property’s natural assets and are valued by the community or simply the tree owner. By requiring tree reports, councils can ensure that the trees are protected and that their value is preserved.

What is an Impact Assessment?

An impact assessment is an evaluation of the potential impact that a proposed construction project may have on trees on the property, the neighbouring property or council land. The assessment will identify any potential impacts on the trees and will recommend ways to minimize or mitigate these impacts. An arborist will conduct the assessment and will provide a report detailing the findings.

Why is it Needed?

An impact assessment is needed to ensure that the trees can survive the construction process. Trees can be damaged by construction activities such as excavation, trenching, and compaction. An impact assessment will help identify potential risks and recommend ways to minimize or mitigate these risks. Where they can’t be mitigated, tree removal is the only option – if the council or tree owner will allow it that is.

What is Assessed?

During an impact assessment, the arborist will assess the trees on the property to determine their size, species, age, health and structure to name a few. They will also assess the location of the trees in relation to the proposed construction and any other structures on the property. The arborist will identify any potential risks to the trees and recommend ways to mitigate these risks.

What Data Do They Take?

The arborist will take data on the size, species, age, and health and structure of the tree, as well as its location in relation to the proposed construction. They will also take data on any potential risks to the tree, such as excavation, trenching, or compaction.

Why are Street Trees Part of the Assessment?

Street trees are often included in the assessment because they are often an important part of the local streetscape. They provide shade, aesthetic beauty, and environmental benefits, and are valued by the community. By including street trees in the assessment, council can ensure that these trees are properly protected during the construction process. Street trees are a council asset and they do not want them damaged.

If It’s My Property, Why Can’t I Do Whatever I Like?

While it is understandable that homeowners want to have control over their own property, there are laws and regulations in place to protect trees and the environment. In many cases, these laws are in place to prevent harm to the environment and to ensure that trees are not unnecessarily damaged or removed. In addition, many trees are protected because they provide important environmental benefits, or benefits to the wider area they are located including aesthetic and recreational benefits.

Local Laws and Planning Provisions in Relation to Trees

In Victoria, the protection of trees is governed by the Planning and Environment Act 1987, the Local Government Act 1989, and the Victorian Planning Provisions. These laws and regulations are designed to protect trees and the environment, and they also ensure that development is sustainable and in line with the community’s expectations.

One of the key aspects of these laws and regulations is the requirement for an impact assessment and tree protection plan.

Differences Between an Impact Assessment and Tree Protection Plan

An impact assessment and tree protection plan are two separate documents, but they are closely related. An impact assessment assesses the potential impact of a development on the environment, including trees, while a tree protection plan outlines the measures that will be taken to protect the trees during construction.

Ideally, both documents are produced by the same arborist. The impact assessment is used to inform the tree protection plan, and the two documents are often submitted together as part of the planning application process.

What Role Does a Site Supervision Arborist Play?

A site supervision arborist is responsible for ensuring that the tree protection plan is implemented correctly during the construction process. This includes monitoring the construction site to ensure that trees are not damaged or removed, and ensuring that the measures outlined in the tree protection plan are being followed. If any issues arise, the site supervision arborist will work with the builder or developer to resolve them and ensure that the trees are protected.

Examples of Tree Protection Zones (TPZ) and Structural Root Zones (SRZ)

Tree protection zones (TPZ) and structural root zones (SRZ) are two important concepts in tree protection during construction. The TPZ is an area around the tree where construction activities are restricted, while the SRZ is the area beneath the soil where the tree’s roots grow. The size of the TPZ and SRZ depends on the size of the tree. These two radial measurements become larger for larger trees.

How Trees can be a Problem for a Construction Site

When designing a construction project, trees can pose a significant challenge when their tree protection zones (TPZs) and structural root zones (SRZs) are in conflict with the proposed design. The TPZ is the area around the tree that is necessary for the tree’s health and survival, while the SRZ is the area where the tree’s roots may cause structural damage to the surrounding structures.

One of the most common ways that trees can be a problem for a design is when their TPZ or SRZ conflicts with the proposed location of a building or other structure. If a tree’s TPZ or SRZ is within the proposed construction area, the design may need to be modified to accommodate the tree or the tree may need to be removed altogether.

Another challenge is that trees can interfere with the installation of utilities, such as water, gas, or electrical lines. If a tree’s roots are in the way during excavation this can damage the tree’s root system and compromise its health.

In some cases, the design may need to be modified to incorporate the trees, such as building around them or creating a buffer zone to protect the TPZ or SRZ. In other cases, the trees may need to be removed.

When designing a construction project, it is important to consider the impact of nearby trees and their TPZs and SRZs. Trees can pose significant challenges and may require modifications to the design or removal altogether. Consulting with a professional arborist can help ensure that the design is compatible with the local tree population and minimize the risk of tree-related issues during and after construction.

Conclusion

In conclusion, getting a planning permit to construct near trees can be a complex process that requires careful consideration and planning. It is important to understand the impact that trees can have on a construction site and to take steps to mitigate any potential damage.

An impact assessment is a critical first step in this process, as it helps to identify any trees that may pose a risk to the construction site. The assessment considers factors such as the tree species, its size and age, and the proximity to the construction site. Based on this information, a tree protection plan may be required to ensure that the trees are not damaged during the construction process.

Local laws and planning provisions must also be considered, as they can dictate what steps must be taken to protect trees during construction. Consulting with a professional arborist can be helpful in navigating these regulations and developing a plan that meets all requirements.

Once construction begins, a site supervision arborist can play an important role in ensuring that the tree protection plan is implemented correctly and that no damage is done to the trees. This includes monitoring the construction site, identifying any potential risks to the trees, and making recommendations for any necessary adjustments to the plan.

While the process of obtaining a planning permit and constructing near trees can be complex, it is important to take the necessary steps to protect both the trees and the construction site. By following the proper procedures and working with professionals, property owners can ensure that their construction project is a success without causing harm to the environment.

Facts about planning permits & trees

An impact assessment is a critical first step in the planning process when constructing near trees.
Local laws and planning provisions must be considered when constructing near trees.
Council trees are always included in the assessment process.
An impact assessment considers factors such as tree species, size and age, and proximity to the construction site.
A tree protection plan may be required to ensure that trees are not damaged during the construction process.
A site supervision arborist can play an important role in ensuring that the tree protection plan is implemented correctly.
Neighbouring trees are always included in the assessment process.
Trees can add value to a property and provide numerous benefits, but they can cause design issues for development.

Links for further reading:

“Tree Protection Zones and Structural Root Zones” by the International Society of Arboriculture: https://www.isa-arbor.com/Portals/0/Assets/PDF/Public%20Outreach/Tip%20Sheets/TPZ-SRZ.pdf
“Planning and building near trees” by the Victorian Government: https://www.planning.vic.gov.au/policy-and-strategy/planning-for-trees-and-vegetation/planning-and-building-near-trees
“Tree Protection During Construction” by the City of Toronto: https://www.toronto.ca/services-payments/building-construction/apply-for-a-permit-or-ltc/tree-protection-during-construction/

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