Urban Trees, Highways and Utilities – Hannah Cook, GreenBlue Urban

Urban Trees, Highways and Utilities – Hannah Cook, GreenBlue Urban

Hannah Cook at GreenBlue Urban emphasises the importance of green infrastructure within the road network as towns and cities across the UK expand. 

With increasing urbanisation of our towns and cities, the pressure to plant trees is huge.

Priorities are under challenge, our road systems, with increasing traffic, need to provide safe pedestrian access suitable for all, and the plethora of below ground constraints create almost impossible hurdles to overcome.

Only as we give our green infrastructure some sort of parity with grey infrastructure in our urban conurbations, will we truly build resilience and create sustainable cities for future generations.

GreenBlue Urban encourage design with canopy cover in mind, as mature trees have multiple benefits; promoting a healthy, biodiverse, and the sustainable city which includes sequestering carbon, mitigating the effects of climate change, and improving our sense of biophilia minimising stress.

In 2015, a collaboration between Highways England, Keir, Treeconomics, Evans Associates, Davey and Forest research published an i-tree eco survey stating that trees planted in South West Region Highways network remove 29 tonnes of pollutants every year.

GreenBlue Urban worked closely with Glasgow City Highways and Civic Engineers on the scheme: Sauchiehall Street in Glasgow. This project was implemented due to the considerable decline in the road’s retailers, so renovation to consolidate the main shopping centre to heart of the city, encouraging customers to visit the shops in person was put into action.

The ‘Green Avenues Plan’ was the driving force to increase canopy cover, with Sauchiehall Street being the perfect pilot to highlight how green infrastructure can be used to change human behaviour, challenging the dominance of vehicles in the public realm.

Twenty-eight specimen trees have been planted in full GreenBlue Urban ArborSystem tree pits provide a strong visual segregation between vehicles and pedestrians/cyclists. Designed as “linked” they provide maximum rooting space in uncompacted soil, giving the trees the best opportunity of attaining species potential.

Beneath the streets lie a labyrinth of interconnected utilities, foundations, and other construction constraints. Many of these constraints are not anticipated, as much of the infrastructure below ground is not well documented.

Guidelines given in the DMRB (Design Manual for Roads and Bridges) HD24 HD26: Pavement Design and Construction, state that the requirement of the road design and surface layer works are to be based principally on a traffic assessment figures. These are expressed in terms of million standards (80kN) axle loads (msa) carried during the design life of the construction. This traffic loading together with the quality of the subgrade dictates the selection of the surfacing and depth of a road pavement required.

The clue to successful tree planting in and around utilities is collaboration and understanding the risks to the utility provider. Trees are not inherently damaging, but they are exploitive of rooting volume, and tend to find the easiest route to nutrient, water, and air. When the initial planting zone has become insufficient for the tree health, the tree roots will explore further areas in search of these items, and in doing so can find small fissures or holes in service ducts and drains.

The complexity of utility runs beneath the paving means that the GreenBlue soil cell system; Rootspace can intertwine around these features, directing the roots into the uncompacted soil chambers. Joining the tree pits beneath ground allows the soil volumes to be reduced, as the trees share the available nutrients and become more resilient than standalone trees would.

The Challenges:

  • We often receive the question: Can you access the tree pits if required after installation? If utilities need to be accessed in the case of an emergency, the contractor simply must excavate to the top of the cell system, remove the RootSpace Lids and hand dig or vacuum excavate through the rooting zone to access the service.
  • Footway constrictions can also be an ongoing issue. GreenBlue advise to use ReRoot Barrier away from these potential issues and into the Cells below the road, allowing root penetration into optimum soil conditions.
  • Adoption of tree planting is a complicated issue, and many local authorities find it hard to maintain the balance between efficiently managing their scant resources and greening up urban areas. Commuted sums vary so it is advisable to be clear from the outset.

Well designed highways networks can deliver economic, social and wellbeing benefits, tree pits for the hard landscape are very much embedded within the narrative of green, blue, biodiverse thoroughfares through the effective use of green infrastructure.

New tree planting is required if we are to ensure a continuum of canopy cover for future generations. Urban tree planting needs emphasis on quality rather than quantity.

“Bringing the environment into the picture” – How local authorities can add a new dimension to highways asset management – Andy Peart, Yotta

“Bringing the environment into the picture” – How local authorities can add a new dimension to highways asset management – Andy Peart, Yotta

Andy Peart outlines how local authorities can utilise tech and data to inform their highways asset management decisions and bring in a new environmental dimension.


The science of strategic highways asset management is going through seismic change. Historically, the approach focused on gauging the financial impact of different road repair and maintenance decisions. Local authorities had to weigh up whether it made sense to save money at the outset by using a less expensive surface treatment, only to have to spend more down the line on road repairs or additional surface dressings. On the other hand, they had to assess whether using more durable but expensive materials from the word go would ultimately prove an economically-sounder decision.

This model is now rapidly evolving. There are a range of drivers. Residents are much more attuned to the importance of sustainable construction. They care about the highways development and maintenance process being environmentally efficient. They want the carbon footprint generated across the highways lifecycle to be kept to a minimum. But they also want councils to take a broader perspective and think about how decisions made about highways management and maintenance might impact the wider community.

Government is also becoming more cogniscent of environmental factors in the way it allocates funding to local authority highways departments. Questions relating to sustainability have recently been included for the first time in the Local Highways Maintenance Incentive Fund.


The impact of technological advances

To meet these kinds of drivers, new predictive analytics technology is now coming on stream, allowing local authorities to base highways management and maintenance decisions on their impact on the wellbeing of residents and the local economy and environment, as well as financial cost and road condition. Thanks to these advances, the authorities can move beyond a pure focus on road conditions to thinking much more about where roads are located, who is using them and what the overall environmental impact of their construction and maintenance will be.

Part of this may be around the ability to analyse where pinch points on the network are causing cars to idle at junctions for long periods of time. Part of it may be around better understanding how infrastructure decisions impact the quality of life in specific neighbourhoods: including projected job creation, support for economic growth, environmental impact, and changes in levels of access to important public resources such as hospitals and schools.

However, a key element of the equation will inevitably be around the treatment used on the surface of the road. Many local authorities are working with larger contractors. The local authority effectively manages the highway while the contractors go out  and lay the tarmac, and, increasingly today as they are doing that, collect information about temperature and CO2 emissions from the scheme. Typically, they will have specifications around different treatments.

These might include assigning a carbon or NOx output to a treatment that can then get added to the overall lifecycle model. It is another example that demonstrates how highways lifecycle planning is becoming ever greener today.

Many councils are still in the early stages of trying to roll put this kind of approach and currently, they are still trying to understand what their baseline is. They need the ability to model these kinds of factors quickly in order to be able to support the decision-making process on new road builds. It may be a nuanced final decision if, for example, one choice may be more expensive financially but also likely to deliver lower carbon output over time compared to the alternatives.


Flexibility of choice

The aim of any asset management solution in this space is not to drive the council’s end decision in any specific direction, it is more around giving local authorities the ability to run different scenarios and then put those options in front of their senior decision-makers. This need to be done as part of an approach which effectively says – ultimately it your decision but we are giving you the best available information to make it.’

These are complex judgements, after all. Low carbon treatments for highways assets are often cheap to invest in. They are therefore attractive to local authorities who want to go ahead quickly with an environmentally-friendly approach. However, if the council is going to have to re-apply the treatment every year, it is going to end up costing more and it is going to output more carbon. So authorities really need to look beyond short-term gains. In this case, for example, they need to consider  whether it might be better to stick to the original road surface, which may be higher carbon at the outset but require much less carbon to maintain over a 30-year lifecycle.

To properly assess that decision, local authorities will need to have the right data available to them, together with the relevant skills to assess that data and the ability to spend time on it and deliver it. Most importantly they will need the right asset management software solution delivered by a vendor they can trust and that can also deliver expert consultancy on top. If they get that formula right, to broaden the overall picture that informs their highways asset management decisions, including bringing a new environmental dimension into it.


Andy is a marketing leader and business strategist with 30+ years’ experience in the AI and B2B software sector. Working with connected asset management leader, Yotta, Andy heads their marketing function and helps ensure the company’s innovative software drives business benefit for its 200+ public and private sector customers. www.weareyotta.com

Yotta are exhibiting once again at Highways UK this year on 2-3 November at the NEC in Birmingham on stand I4

ADEPT President Paula Hewitt looks back at the ADEPT SMART Places Live Labs programme

ADEPT President Paula Hewitt looks back at the ADEPT SMART Places Live Labs programme

Paula Hewitt, President, ADEPT

I think it’s fair to say that the ADEPT SMART Places Live Labs Programme has at times been a wild ride.

What began as a desktop review into the digital transformation of local roads, became a wide-ranging series of trials that battled through complex procurement challenges, a global pandemic and consequent supply chain difficulties, and the redesign and reassessment of technologies, to become a successful showcase for how to implement innovation across local highways. And many of the tested technologies will make a contribution to reaching net zero!

The £22.9million Department for Transport funded two year programme, initiated and designed by ADEPT, was a collaboration of private and public sector, national and global companies, academia and SMEs all working together across eight different Live Labs. Led by a local authority, each Live Lab set up and implemented a number of trials across data, communications, materials, energy and mobility.

Trials have included:

  • Harvesting kinetic energy from pavements to power digital screens and provide public charging points
  • Using thermal energy to de-ice carparks plus light and heat workshops
  • Using solar surfacing on roads to power buildings
  • Trialling using sensors, VivaCity cameras on waste lorries and drones to assess highways and local roads’ maintenance needs
  • Creating composite recycled lighting columns with sensors
  • Examining last mile mobility
  • Testing the environmental sustainability and quality of using waste plastics in roads
  • Creating data analytics to support air quality management areas and public health
  • Managing congestion using data and video analytics to create personalised travel planning through understanding travel behaviour

The results have far surpassed initial expectations, with key outcomes for the programme also encompassing behavioural change, cross-authority collaboration and a re-examination of public sector approaches to risk and innovation. Central to the programme has also been commercialisation, and the final outputs will include a series of business cases from each Live Lab. These will detail the technical, commercial and supporting data that will enable other local authorities and the wider sector to assess the suitability of an innovation for its own geography and needs.

Many of the lead authorities are taking their work beyond the lifetime of their Live Lab, creating internal cross-sector Innovation and Technology Boards and attracting additional funding and resource opportunities. Others are working with councils outside the programme, for example to discuss how ‘living walls’ can be incorporated into local bus strategies to improve localised air quality. There has even been crossover to other sectors, with two Live Labs exploring how their technology could be used to support adult social care.

Of course, the programme has not been without its own challenges, and if we are successful in moving forward with Live Labs 2, there is much we can build on and incorporate into a new programme.

In the early days, the interpretation of procurement rules differed widely across local authorities, to the extent that some lost the first six months of the two year programme trying to resolve issues. Fast innovation projects cannot bear that sort of delay and we will need to design a new flexible approach that can work through contractual restraints at pace. Although most Live labs were able to adapt to setbacks, for projects that were hugely ambitious and complex in scope, some problems proved difficult to overcome, also resulting in delays.

This type of evaluation and shared learning is all part of the Live Labs ethos. We set out to capture everything – the successes, the challenges, outcomes and failures – and make it all publicly available. We have published white papers, reports, articles and blogs as well as taken part in webinars, conferences and delivered two Live Lab Expos. I would also encourage you to watch the Women in Transport video, where our four female project leads discuss their careers and what it takes to be a female leader in the highways sector with ADEPT CEO, Hannah Bartram. It’s both illuminating and inspiring!

I’d like to thank our lead authorities – Buckinghamshire Council, Central Bedfordshire Council, Cumbria County Council, Kent County Council, Reading Borough Council, Staffordshire County Council, Suffolk County Council and Transport for West Midlands – for their tenacity, humour and creativity, exactly the approach you need when a global pandemic gets in the way of the best laid plans!

Suffolk County Council is setting up a platform where the business cases will be freely available, and you will be able to find details for this when its ready, and much more, on the ADEPT website: www.adeptnet.org.uk/livelabs.


More information on the ADEPT SMART Places Live Labs programme can be found here: https://www.adeptnet.org.uk/livelabs

The Women in Transport video is available to view here: https://www.youtube.com/watch?v=ezk3cBwCSVk

About the ADEPT Smart Places Live Labs programme

The ADEPT SMART Places Programme is a five-year project examining and developing innovation to enable the adoption of innovative and digital technology across the local highway network. The initial research report ‘Digital Innovation: The route to the highways systems of the future’ was published in October 2017. In January 2019, ADEPT secured £22.9 million funding from the Department for Transport for Phase 3 of the programme, which sees the development of eight individual Live Labs projects led by local authorities across England with university and private sector partners. The Live Labs are piloting innovation across SMART communications, transport, highways maintenance, energy, materials and mobility. The ADEPT SMART Places programme has been developed with partners: SNC-Lavalin’s Atkins business, EY, Kier, 02, Ringway and WSP.


The Association of Directors of Environment, Economy, Planning and Transport (ADEPT) represents local authority county, unitary and metropolitan Place Directors. Operating at the strategic tier of local government, members are responsible for delivering public services that primarily relate to the physical environment and the economy, but which have a significant impact on all aspects of the nation’s well-being. ADEPT represents members’ interests by proactively engaging central Government on emerging policy and issues, promoting initiatives aimed at influencing Government policy and through the development of best practices and responding to European and UK Government initiatives and consultations. Out wider membership includes Local Enterprise Partnerships, Combined Authorities, Sub-national Transport Bodies and Corporate Partners.


ADEPT is an official partner of Highways UK, for more on ADEPT visit: www.adeptnet.org.uk

Paula Hewitt, this year’s President of ADEPT, will be speaking at Highways UK 2022 in the Local Authority Hub at the NEC in Birmingham on 2-3 November.