Arboricultural Impact Assessment – A Comprehensive Guide

arboricultural impact assessment guide

An arboricultural impact assessment (AIA) is a document that is compiled by a qualified arborist to assess the potential harm that could be caused to trees as a result of a proposed development. The assessment looks at things like the size, health and location of trees in relation to the planned development, and will make recommendations about how best to protect them. AIAs are required for various types of development projects, and it is important that they are carried out by a qualified professional in order to ensure accurate results.

In this article, we will explain everything you need to know about arboricultural impact assessments, including what they are, why they are important and when they need to be carried out.

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What does an Arboricultural Impact Assessment Look At?

AIAs are important documents that assess the potential impact that a proposed development could have on existing trees. They are done by a professional Arboriculturalist who will take into account various factors when compiling the report, such as the size and health of the trees, their location in relation to the planned development and any previous work that has been carried out nearby.

The Purpose of an Assessment

An AIA is carried out for a number of reasons, but the primary purpose is to make sure that trees are not harmed during or as a result of the proposed development. The assessment will also look at ways to protect existing trees and ensure their long-term health, as well as make recommendations about new planting. This is important because trees can provide many benefits to a development, such as screening, shading and amenity as well as being an important part of the natural environment.

When does the Assessment Need to Be Done?

AIAs are required for some types of development, but not all. In general, they are needed for anything that could potentially damage trees, such as excavation work or the construction of new buildings. However, each project is different and you should check with your local planning authority to see if an assessment is required.

They will consider the size and type of development, as well as the number of trees that could be affected. If there are a large number of trees or if they are particularly valuable, then an assessment is more likely to be needed. If they decide that you need to do one, it will take place before work starts on site.

Which Projects Require It?

AIAs are most often required for larger developments, such as housing estates or office blocks. They may also be needed for smaller projects, such as the construction of a new driveway or the installation of a fence if there is a risk of damage to trees.

Do not assume that your project does/doesn’t require an assessment because of its size – each case is decided on its individual merits.

Issues that it Identifies

The AIA will identify any potential risks to trees from the proposed development. These may include:

  • Excavations near the tree’s roots – This could damage the roots and affect the tree’s stability. The assessment will look at the total root area as well as the depth and location of the excavation to see if there is a risk.
  • Damage caused by heavy construction vehicles – If large vehicles are going to be used on the site, they could damage the roots or compact the soil, which would affect the tree’s health. The assessment will look at the type of vehicles to be used, as well as their weight and how close they will get to the tree.
  • Buildings close to a tree’s branches or roots – If a new building is going to be built close to a tree, it could damage the roots or affect the tree’s growth. The assessment will look at the size and type of building, as well as its proximity to the tree.
  • Protected tree species – There are some tree species that are protected by law, such as ancient trees or veteran trees. If these are going to be affected by the development, then the assessment will need to look at ways to protect them. There are various trees on the UK protection list so you need to make sure you are mindful of that when working on a construction project.

guide to arboricultural impact assessments

Potential Recommended Protection Measures

Depending on the risks identified, the AIA may recommend various protection measures. These could include:

  • Tree protection fencing – This is used to protect trees from damage by construction vehicles or machinery. The fence should be put in place before work starts on site and should be removed when the work is finished.
  • Construction exclusion zones – This is an area around the tree that construction workers are not allowed to enter. This helps to protect the roots and avoid compaction of the soil which can lead to damage.
  • Tree-friendly construction techniques – There are certain construction techniques that can be used which minimise the risk of damage to trees. For example, using a ‘moleskin’ to protect tree roots when excavating near them. You may also need to use methods such as hand-digging rather than using machinery, which can reduce the risk of damage to roots.
  • Safe storage areas – If there is a risk of damage from construction materials or machinery, then these should be stored away from the tree. This helps to reduce the risk of accidental damage.

How to Get a Survey

If you think you may need an AIA, then you should contact a qualified arboriculturist or tree surveyor. They will be able to carry out a site visit and assess whether an assessment is needed. There are various arborists and surveyors who provide Arboricultural Impact Assessments so it is always worth shopping around to get the best price.

At Indigo Surveys, we specialise in a range of different tree surveys and can provide you with a comprehensive AIA for your upcoming construction project. We have teams of qualified arborists all around the UK who are experienced in carrying out these assessments and will be able to provide you with all the information you need.

We guarantee:

  • No hidden costs – The price we quote is the price you pay.
  • A comprehensive report – Our reports are clear and concise, with all the information you need to make an informed decision about your project and to abide by any planning regulations.
  • A highly-competitive quote – So you can be sure you are getting the best value for money.
  • Upfront advice – We will always give you honest and impartial advice about whether an AIA is needed for your project.

If you would like to find out more about our services or get a quote, then please contact us today. We would be more than happy to help you with your upcoming project.

What Happens After You Book an Assessment?

Once you have booked an assessment, our team of qualified arborists will visit your site to carry out a survey. They will assess the trees on-site and identify any risks that could be posed by the proposed development. They will also look at ways to mitigate these risks and protect the trees during construction.

After the survey has been carried out, our team will produce a report which will detail their findings and recommendations. This report will be sent to you so that you can make an informed decision about your project.

If you decide to go ahead with the development, then our team can provide you with ongoing support to ensure that the trees are protected during construction. We can also provide you with advice on tree planting and aftercare to ensure that your new trees thrive in their new environment.

Do you need to Submit the Assessment?

Once you have received the AIA report, you may need to submit it as part of your planning application. This will depend on the council’s requirements and the type of development you are proposing.

If you do need to submit the report, then our team can help you to do this. We can also liaise with the planning department on your behalf to ensure that your application is processed smoothly.

understanding arboricultural impact assessments

What Qualifications does the Arboriculturalist/Surveyor Require?

In order to carry out an AIA, the arboriculturalist or surveyor must have a minimum of Level III in Arboriculture. They must also be experienced in carrying out these types of assessments and be familiar with the planning process. At Indigo Surveys, we have over ten years of experience in both commercial and domestic surveys. All of our team members are qualified and experienced in carrying out AIAs and can provide you with the support you need.

How Much Does an Assessment Cost?

The cost of an AIA will vary depending on the size and location of the site, as well as the number of trees that need to be surveyed. Our tree surveys start from £200 but this will depend on a number of factors such as site location and tree number.

If you would like to find out more about our services or get a quote for an AIA, then please contact us today. We would be more than happy to help you with your upcoming project.

Could an Assessment Lead to a Project Being Restricted/Rejected?

An AIA is designed to protect trees during the construction process. However, in some cases, the assessment may identify issues that could lead to the project being restricted or rejected.

For example, if the survey identifies that the proposed development will damage the roots of a tree, then this could lead to the project being rejected by the council. In this instance, the arborist or surveyor may recommend tree protection measures such as root barriers or construction exclusion zones.

Another potential issue is if the proposed development will cut down trees that are protected by a Tree Preservation Order (TPO). In this instance, the project will need to be approved by the council before it can go ahead.

It is important to note that an AIA is not a guarantee that your project will be approved. However, it will identify any potential risks and provide recommendations on how to mitigate these risks so that you can negotiate with the council.

What if the Arboriculturalist/Surveyor Finds no Issues?

If the arboriculturalist or surveyor finds no issues with the proposed development, then they will provide you with a report to this effect. This report can be used as part of your planning application and will help to speed up the process.

It is important to remember that even if the arboriculturalist or surveyor finds no issues, you may still need to submit the report as part of your planning application. Again, this will depend on the council’s requirements and the type of development you are proposing.

Other Types of Tree Surveys

As well as AIAs, there are a number of other types of tree surveys that you may need to carry out. These include:

  • Tree Constraints Plans – these are often required by utility companies and show the position of underground cables and pipes in relation to trees.
  • Construction Method Statements – these detail how the construction work will be carried out and what measures will be put in place to protect trees.
  • Tree Risk Assessments – these assess the risk of a tree falling and causing damage to people or property.

Each of these surveys has a different purpose and will be required for different projects. Click here to find out more about the range of surveys we provide as well as more information about what they involve and when they are required.

arboricultural impact assessment

To Sum Up

An arboricultural impact assessment is a survey that is carried out to assess the impact of a proposed development on trees. The assessment will identify any potential risks and provide recommendations on how to mitigate these risks. If you are starting a new construction project either at home or commercially, get in touch with us today to see how we can help you.

Andrew Turnbull

As a co-Director of this multidisciplinary company, Andrew handles various responsibilities related to business management, administration, and operations. His role involves tasks such as overseeing company structure and policies, managing creational control, handling marketing and events, engaging with clients, preparing quotations, managing contracts, coordinating with sub-contractors, and providing arboricultural consultancy.