Council Development Applications

Trees are often overlooked at the earliest stages of planning for development; however, they are one of the most important considerations. If key tree issues are not resolved early, it can have a significant impact on the fees, timing, and chances of a smooth and successful development application (DA). If issues or conflicts are ignored or overlooked, they will be identified and raised by the council (consent authority) following DA lodgement and may result in DA refusal.

Key issues

Key tree issues that are often overlooked include, but are not limited to the following:

• Important trees in adjoining properties: Trees located on adjoining properties are not considered or assessed.
• Important trees within the site: Important trees within the site are not flagged or considered.

It is important for the consulting arborist to identify constraints and opportunities early so they can be addressed and resolved. If key constraints are not identified and addressed, they have the potential to result in any one or more of the following outcomes:

• DA refusal: The council may refuse the application, or issue deferred commencement consent.
• Redesigns and revisions: Consultants’ plans, drawings, and reports may need to be amended.
• Additional fees: Additional consulting fees and drafting fees.
• Significant delays: Additional delays while consultants undertake revisions and updates.

Engaging experienced and knowledgeable consulting arborists like Tree Survey will ensure constraints and opportunities are identified early so they can be addressed and resolved, ensuring a smooth and efficient DA approval.

Important trees in adjoining properties

Trees on adjoining property are a key concern for councils. Development applications are regularly refused because works proposed within the subject site will impact trees located outside the site (on adjoining or neighbouring property). Trees do not recognise cadastral boundaries. Roots and branches will develop in areas most conducive to growth and will often extend beyond boundary lines and into the zone of influence (proposed construction footprint). The Australian Standard, Protection of Trees on Development Sites (AS4970), describes two zones that need to be considered when planning for trees and proposed development:

• Tree protection zone (TPZ): The TPZ is the combination of crown and root area that requires protection during the construction process so that the tree can remain viable. The TPZ is calculated by measuring the DBH and multiplying it by twelve (12). The resulting value is applied as a radial measurement from the centre of the trunk to delineate the TPZ.
• Structural root zone (SRZ): The SRZ is the area of the root system used for stability, mechanical support, and anchorage of the tree.

The TPZ of trees located on adjoining property will often extend beyond the boundary and into the zone of influence, especially if the tree is large and close to the boundary. Some encroachment (construction) within the TPZ is acceptable under most circumstances, especially if the encroachment does not exceed 10% of the overall TPZ area. Encroachment of less than 10% is considered a minor encroachment under AS4970 and is generally supported by councils. Encroachment greater than 10% of the TPZ is considered a “major encroachment” under AS4970. Consent authorities are unlikely to support major encroachments for trees on neighboring or adjoining properties. There are two (2) pathways forward if a tree located on adjoining property will be subject to a major encroachment:

• Design adjustment: The key factor for the successful retention of trees is providing adequate construction setbacks by maximising the distance between trees and infrastructure. This is achieved through design strategies such as the relocation or modification of structures, services, and hardscapes. Ensuring adequate distance between the tree and the construction footprint not only reduces the impact on trees but also reduces the likelihood of trees causing damage to infrastructure in the future.

• Owner’s consent: Trees are considered an asset to the property on which it is located, and consent authorities will not give permission to remove a tree on an adjoining property without written consent from that property owner. If the owner’s consent is acquired, the council may (or may not) support the removal of the tree.

Unless written consent is provided, the applicant must ensure that neighbouring trees are not impacted by the development. Trees growing on a shared boundary (joint ownership) are treated the same as a tree located on adjoining properties. Joint consent is required to apply for tree removal. If written consent is not provided, the applicant must ensure that the trees located on the boundary are not impacted by the development. Trees on adjoining or neighbouring sites are equally, if not more important than trees within the subject site are a key focus for Tree Survey. They are often the most important consideration and have the potential to completely roadblock the DA process.

Important trees within the site

There is greater flexibility for trees within the site, however, high-value trees should be identified and considered at the concept design stage. Too often, arborists do not identify important trees, and designs do not accommodate them. There are no issues with prioritising the design over trees, but there are risks involved. On many occasions, the developer and design team are unaware of these tree issues and risks, until they are raised by the council following DA lodgement. Significant resources may be spent on proposals that are highly unlikely to be approved. Tree Survey takes time and care at the early stages to make sure we provide all relevant data and feedback so the property owner can make informed decisions about the pathway they choose. If important trees are identified within the site, there are two (2) pathways forward:

• Design is the priority: If trees are not a key priority, the developer may choose to maximize design, yield, or profit in preference to retaining existing trees. There is no issue with this approach provided the developer understands the risks and potential setbacks associated with this approach. The downside of proposing a design that does not accommodate or consider trees is that it may weaken the chances of a smooth and successful DA approval. The benefit of this approach is if the DA is approved without issue, the optimal design was not preemptively adjusted or compromised to retain trees that may (or may not) have been approved for removal. It is often the case that developers will put forward their preferred design in the first instance and if the DA is refused, they will compromise and adjust to suit. In either circumstance, it is important for the developer to be aware of the important trees, and potential issues, so they can make informed decisions about the preferred pathway forward.
• Approval is the priority: If a smooth and successful DA approval is the priority, then the design should accommodate the important trees wherever possible, maximising the chances of a smooth and successful DA approval. There are many design options and tree-sensitive engineering options that may allow the retention of important trees, without significant design adjustments or compromises.

Engage with a consulting arborists

Engaging experienced and knowledgeable consulting arborists like us (Tree Survey) will ensure constraints and opportunities are identified early so the developer can make so they can make informed decisions about the preferred pathway forward.