Greening Gilbert Road Through Tree Planting

Proposal

To plant new trees along the south side of Gilbert Road at the Milton Road end, near The Fellows House (TFH) Aparthotel. The aspiration is to replace lost trees and plant new trees to re-green and reclaim this end of the road from further unsightly development, and to improve the wellbeing of people, wildlife, the environment and the street scene.

Background

In recent years this part of Gilbert Road has suffered from a decline in tree canopy cover, a significant impact being from commercial development and with it extensive hard landscaping affecting the residential setting of the area. Where mature trees once stood, there now lies a long, wide expanse of concrete and tarmac occupied by unattractive utility cabinets, telecommunications masts/poles, hire cycle and scooter parking zones, and the attendant vehicle parking issues, with the prospect of further development creeping along the road.

Benefits

The aim of this proposal is to start to aid the recovery of this area for people and biodiversity by restoring trees to this end of Gilbert Road. Establishing trees will also set a positive precedent and prevent the creep of further unsuitable developments. The proposal has the full support of local residents, as well as all three city councillors for West Chesterton and the county councillor for Arbury.

There are minor issues with tree planting including the need for maintenance (residents have agreed to assist in this); however, trees offer a huge and widespread benefit to our city and contribute to the character and beauty of Cambridge. They are not only integral in providing cleaner air by filtering, and capturing storm water and lowering city temperatures, they also create an important habitat for birds and insects. Streets, parks, and housing estates filled with trees also have significant psychological benefits for residents, reducing stress and providing spaces for relaxation and contact with nature. As well as benefitting nearby residents, these trees would also be beneficial to anyone travelling along Gilbert Road or Milton Road.

The City Council is committed to increasing the tree canopy cover of Cambridge from 17% to 19% with increased tree planting forming a substantial part of that increment.

Added to this Cambridge City Council has a commitment to reduce the city’s carbon emissions to lessen the impacts of climate change on residents, businesses and visitors. The Council, through its Climate Change Strategy 2021-2026 and Tree Strategy 2016-2026, has expectations for Cambridge to achieve zero carbon status by 2030 and the overall tree canopy cover is a crucial component of these strategies.

We need to consider the existing mature trees presently found in Gilbert Road and those lost, and the importance of planting a replacement generation of trees to ensure we have a continuity of tree cover in the area before any more trees are lost. We are not only planting for the present but also for the future; we must imagine the landscape and climate for living in during the 2050s.

Expectations

The City Council Tree Team have identified seven locations for new tree planting (four are the verge by properties 11 to 19 inclusive) on Gilbert Road. With appropriate funding the proposed works will include:

• Trial pits to determine the construction of the existing highway and the location of below ground utility lines
• Construction of engineered tree pits using structural soil cells.
• Planting the trees in the prepared pits

Soil cells provide structural stability for paved surfaces, while their large open spaces provide opportunities for tree roots to grow ensuring the new trees successfully mature in their urban environment.

Funding Requirement

The project costs will be approximately as follows:

• Trial pits – £500 per trial pit. These will identify obstacles below ground level, and the depth of services present, required to assess feasibility in each location for a full tree pit.
• Excavation – £1,000 per tree pit is required to break and dig out the area to construct the final tree pit system.
• Construction of an engineered tree pit – £2.5k per pit. This includes installation of soil cells, root directors and other components.
• Cost to supply and plant a tree (including the tree itself plus stakes, tree ties, mulching, watering in etc.) – £250 per tree
• Traffic management over the course of the project – approx. £1,250. This includes an application to the Highways Authority to work on the public highway, plus erecting barriers and signage.
• Reconstruction of the public highway following the project – £350. This includes tying into the existing surface level, and removal and disposal of waste material.

Therefore, a funding allocation of £20,000 will enable the planting of up to four trees, making the most effective use of funds by dividing fixed overall costs across several trees. This project will have a meaningful impact on regreening and reclaiming this section of Gilbert Road for biodiversity, both for present and for future generations.