PROJECTS

Supporting the delivery of Devon’s new Garden Village

Project: Treasbeare Garden Village
Location: Cranbrook, Devon
Client: Redrow Homes Ltd and Carden Group
Services: Transport Planning

Bringing together all the moving parts to shape healthier, more sustainable neighbourhoods

The Project

Treasbeare Garden Village is part of the planned mixed-use expansion of a new town – Cranbrook – in Devon, comprising up to 1,035 dwellings, a neighbourhood centre, a 420-place primary school, 10.25 ha of employment land and a multi-use sports hub.

Redrow Homes Ltd and Carden Group called upon the expertise of Calibro’s transport planning specialists to provide masterplan advice, technical highway capacity and sustainability assessments to help shape proposals for an outline planning application.

The Challenge

Treasbeare Garden Village, (together with a proposed expansion area known as Bluehayes) will form the new western gateway to Cranbrook – welcoming residents and visitors to the settlement.

Image © Barton Willmore

But although Treasbeare Garden Village is a significant development in its own right, it accounts for less than a quarter of the total planned expansion of the town.

So, while the effects of the additional expansion areas didn’t technically fall under our purview, we nevertheless took a holistic view of the entire project – knowing from experience that all elements of a development are intrinsically linked, and should be treated so by all developers.

As such, we needed to take considerable care with the placemaking agenda. Taking into account any cumulative effects from the other developments, incorporating inter-related policies and co-ordinating across different projects.

We had to ensure we planned for well-defined streets and spaces that would encourage walkable neighbourhoods, and key connections that would make navigation around this growing settlement as easy as possible.

Sounds idyllic, doesn’t it? But easier said than done.

It took some serious creative problem solving to achieve, due to local topography and the position of an existing highway – in places, London Road is around three metres lower than the site itself!

Creating easily navigable towns and walkable communities requires painstaking attention to ALL areas of a development.

The Solution

Gaining a better view

Roads play an important role in supporting a sense of arrival to the place. So, in planning the main junction, we made the bold recommendation to move away from the standard roundabout solution originally suggested for Cranbrook.

In fact, previous planning applications had proposed making the roundabout even bigger, to accommodate increasing traffic volume from more housing. But while making things bigger is the typical response in our industry, Calibro isn’t your typical consultancy. When met with unique challenges we always seek out the best solutions that champion progress and innovation.

Of course, symmetrical roundabouts have their place. But we recognised that as a new town, Cranbrook has the opportunity to balance the needs of modern living, with relatively standard street types in a planned hierarchy. This is far more efficient than the fluid street structure found in settlements that have grown organically over time.

Reflecting on this, we proposed to move away from a solution where four highway links congregated in one junction, instead realigning the main road and using level-surface/landscape design principles to create a landscape-led ‘double-mini roundabout’.

This reconfigured junction would punctuate arrival to the town with a terminus of views, avoiding the sense of the main road being a bypass for the town. It would also create a landscape buffer for the existing housing on one side of the road, helping to reduce nuisance from traffic noise.

Modelling a more sustainable future

Traditional traffic models would struggle to accurately replicate this more unusual design. To solve this, we developed a microsimulation of the local highway network using VISSIM, to model individual driver behaviour for every vehicle on the network in real time.

 

We also ensured the model allowed for complex relationships between land uses on and around the site to avoid ‘double counting’ of traffic. In this way, we were able to allow for the fact that some residents might travel to the proposed primary school on foot, whilst others would travel by car, then continue towards their place of work.

We presented a detailed transport assessment report and accompanying travel plan, in order to encourage the relevant authorities to reduce car travel. We also carried out a transport environmental impact assessment to consider the magnitude and significance of the changes in environmental terms.

We developed a microsimulation of the local highway network, modelling individual driver behaviour for every vehicle, in real time.

The Conclusion

A comprehensive and well-constructed outline planning application was submitted to East Devon District Council in July 2022 and received resolution to grant planning permission in January 2023.

All images © Barton Willmore

I’ve been impressed with the energy that Calibro has brought to this project. From first getting under the skin of emerging policies and identifying place-driven solutions to the access strategy – all have allowed us to put together a unique offer in the context of Cranbrook.

They’ve broken down the problems and solutions into bitesize chunks which has made my life easier in making decisions that protect value in the project. I certainly feel we had the right consultants on this project.

Andy
Redrow Homes
Planning Director

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