Barnet Council's Planning Committee has sparked debate over subsidence and tree preservation following a decision regarding an oak tree at 83 Marsh Lane.
The committee convened on 21 July 2025, to discuss an application (reference TPP/0578/24) to fell the tree, which is protected by a Tree Preservation Order, due to alleged subsidence damage to a neighbouring property.
The application sought permission to fell the oak tree at 83 Marsh Lane, with supporting documentation suggesting the tree's removal would allow a neighbouring property to stabilise. The applicant provided an engineering report and supporting documentation including:
- MWA Arboricultural Report 25/10/2023
- Crawford's Add Arb Report dated 10/05/2024, updated Oct 2024
- Crawford's Tech Report undated
- Auger SI Report 17/02/2023
- Auger SI Report 30/07/2024
- MHN Level Monitoring 19/12/2022 01/10/2024
- William Hunt Satellite Monitoring 10/032021 30/01/2023
The evidence included identification of oak tree roots within a trial hole closest to the oak, suction tests indicating desiccated soil, and level monitoring results confirming swelling and shrinking of the soil. The applicant's engineers stated that without the tree's removal, underpinning work costing over £180,000 would be required. The Committee Report 83 Marsh Lane 1 indicates that the repair works for 85 Marsh Lane may be in excess of an extra £180,000 if the subject oak tree is retained, which could be the estimated cost to the council if they are liable to pay compensation to the applicant.
However, the council's structural engineers assessed the evidence and agreed that the oak tree was implicated in the subsidence damage. The planning officer's report also noted that if the committee refused permission for the felling, the council may be liable to pay compensation to the applicant.
The Committee Report 83 Marsh Lane 1 states that the Town and Country Planning (Tree Preservation) (England) Regulations 2012 provide that compensation is payable for loss or damage in consequence of refusal of consent or grant subject to conditions. The provisions include that compensation shall be payable to a person for loss or damage which, having regard to the application and the documents and particulars accompanying it, was reasonably foreseeable when consent was refused or was granted subject to conditions.
The statutory compensation liability arises for loss or damage in consequence of a refusal of consent or grant subject to conditions - a direct causal link has to be established between the decision giving rise to the claim and the loss or damage claimed for (having regard to the application and the documents and particulars accompanying it).
Factors that influence the amount of compensation include whether the roots of the oak tree are the 'effective and substantial' cause of damage or whether they 'materially contributed to the damage' and that the damage would be addressed by the felling of these trees.
The report pack included a visual amenity valuation of the tree, using the Helliwell system, giving the tree an amenity score of £3,625.20. The Helliwell system is a method for assessing the amenity value of trees and woodlands. It takes into account factors such as size, duration, importance, tree cover, suitability to setting, and form. The amenity score of £3,625.20 was calculated using this system. The Committee Report 83 Marsh Lane 1 states that the tree scores 6 x 3 x 2 x 1 x 2 x 1 making an amenity score of 72 x £50.35 provides an amenity of £3,625.20. The amenity value is weighed against the potential financial implications for the public purse if the tree felling is refused.
Alternative solutions, besides felling the tree, were considered to mitigate the subsidence issue and preserve the tree. The Committee Report 83 Marsh Lane 1 mentions that the applicants have not provided any supporting evidence that the alternative lesser treatment of installing a root barrier would be problematic.
Ultimately, the committee voted to refuse the application at a previous meeting on 9 June 2025. The minutes from that meeting indicate that the committee voted against the officer's recommendation to approve the felling. The Planning Officer recommended approving the application subject to conditions. However, the meeting transcript does not contain any information about the Planning Committee overruling the planning officer's recommendation and refusing the application. The report states that if the committee refused permission for the felling, the council may be liable to pay compensation to the applicant.