A major project, like building the new Sizewell C nuclear power plant, can take decades to plan. Gaining approval requires planning not just for the project itself, but also for supporting transport infrastructure. How should engineers engage with stakeholders as they plan a project like this, and how can policymakers ensure that public concerns are heard and responded to? 

The UK, like many countries, plans to build new nuclear generating capacity to support the transition away from fossil fuels. The country’s government wants to see 24GW of power sourced from nuclear by 2050. Two projects—Hinkley Point, and Sizewell—will provide a quarter, or 6GW, of this supply.

Construction work is underway on Hinkley Point. In July 2022, consent was given to plans for a new power station, Sizewell C. But getting to this point has been a major undertaking. For John Hicks, technical director, transport planning, at WSP, the preparation for the planning process has dominated his working life for a decade.

The project was approved using a relatively new process, the Development Consent Order, or DCO. This streamlines approval, with all questions considered in a single process. But making that process work efficiently requires considerable planning.

“The first round of questions that came through from the examining authority, numbered 2,229 questions. And that was a record at the time for any DCO,” says Hicks. “When I started on it, it frightened me to death, frankly. The scale of it is unbelievable, absolutely unbelievable. A normal project would be doing the Sizewell Link Road, but we’re doing the Sizewell Link Road, the green rail route, the Two Village Bypass, two Park & Rides, a freight Management Facility, etc, etc, all at the same time. This dominated my life for 10 years. You live and breathe it.”

Nick Cottman, director at WSP, worked alongside Hicks to develop the proposal, and steered it through the consultation process. “There were 1,282 affected parties that submitted relevant representations through the process. There were nearly 4400 documents on the planning inspector’s website that relate to the application. And many of these, of course, are enormous documents in themselves. 

“The Secretary of State’s decision letter that was issued on the 20th of July with the decision was 194 pages itself, and that sat alongside 1,500 pages from the Planning Inspectorate inspector’s report.” 

Navigating the energy trilemma

The UK is caught on the horns of the energy trilemma: That is, the challenge of balancing energy cost, security, and sustainability. Disease and war have rocked global energy markets, causing prices to skyrocket.  Countries around the world face difficult choices between buying fossil fuels from rivals or uneasy allies, or enduring blackouts. And this continued reliance on fossil fuels threatens Net Zero goals.

Nuclear power looks likely to be a key element in resolving these challenges. It will allow power to be reliably produced, without requiring fossil fuel imports. It will provide baseline power, supporting national demands that cannot be met at all times by renewables like wind and solar power. In conjunction with renewable energy, it promises a reliable and affordable source of power, produced locally.

A new nuclear power station is being developed by EDF on the UK’s east coast, Sizewell C. As well as helping meet the UK’s energy needs, it will employ thousands of people in its construction. Across the country as a whole, it will support the creation of around 70,000 jobs.

Any project of this scale will have complex transport requirements. Millions of tonnes of construction materials must be brought to the site. Hundreds of very large or heavy loads must be transported. And thousands of people will have to get to the site each day.

Sizewell A was one of the first nuclear power plants built in the UK, opening in 1966. A second plant, Sizewell B, was added to the complex in the 1990s. And a third, Sizewell C, has now been given the go-ahead to begin construction, with power generation expected to start in the mid-2030s.

Like all nuclear power plants, Sizewell is in a rural location, close to the sea. This has some advantages: many loads can be transported by sea. But it means too that the engineers working on the project must find ways to accommodate vastly increased road and rail use, in an area with limited existing infrastructure. 

Many local people welcome the jobs that the project will bring. But there are also reasons for them to be concerned about the transport impacts. 

Traditionally, projects like this have had to go through a years-long planning inquiry process. The process used to plan Sizewell C, called a Development Consent Order, or DCO, was relatively new when planning started. This sets clear timetables for the examination of a project, allowing project owners to engage with stakeholders and answer all of their questions. At the end of the process, the government gives a clear decision on all aspects of the plan.

The local view

Hicks understands the concerns of local residents as much as anyone could: he is one. “Suffolk, which is actually where I live, is a very rural and largely agricultural environment, of predominantly small towns and villages with relatively poor transport infrastructure, particularly on the east side of the county where Sizewell is,” he says. 

“The site itself is within an area of outstanding natural beauty. And the site itself is adjacent to an SSSI, a Site of Special Scientific Interest. This is gently rolling countryside, very picturesque, with a strong tourism industry, quite remote, and therefore, in a sense an ideal location for a nuclear power station: You don’t build them in the middle of Birmingham, you build them in remote locations next to the sea.”

This might be a rural area, but Sizewell has many neighbours, with diverse interests, and it was important that their voices are heard in the planning and approval process.

“The two largest towns in Suffolk are Ipswich to the south, about 45 kilometres away, which has a population of 140,000, and Lowestoft to the north, about 40 kilometres away, with 75,000 people living there. But the nearest small town to the Sizewell site is Leiston, which has a population of about 6,000. And that’s three kilometres to the west.,” explains Hicks. “So it’s a predominantly rural environment, but one that’s familiar with nuclear because Sizewell A started generating power in 1966, and Sizewell B, which is still operational, in 1995.”

Many locals, particularly the young, are excited about the job opportunities provided by the plans. But others—often older, incoming, pensioners—have concerns about how the construction of the plant and the associated traffic will affect their enjoyment of the countryside.

Planning the project, and the transport infrastructure that would enable its construction, required engaging with multiple local stakeholders. To address all of these stakeholders concerns, EDF needed a clear picture of transport requirements. They asked Hicks and the consultant team at WSP to help them understand and model this.

“There are two key requirements,” says Hicks. “We think about the workforce and what the requirements are for moving thousands of people to work each day. And what are the requirements for materials and freight that we have to move: there are millions of tonnes of materials to import to the site to construct a nuclear power station.”

At the peak of construction, expected around 2028, there will be more than 7,900 workers on site. Some will stay on a nearby campus. Others will commute in from nearby towns, making use of a dedicated park and ride service to reduce traffic on local roads.

Sizewell C is the second of two plants being built in the UK by EDF. The first project, Hinkley Point, provided a model for how the site would be built, and the materials that would be needed in its construction.  It showed that just over 12 million tonnes of materials will need to be imported to build the project. About 40% of that is cement and aggregates, which will come from within the UK.

As well as the bulk materials that will be used to build the plant, it also requires a firm and well engineered foundation to stand on. That means rocky material, with well understood properties, not the soft and inconsistent material found on a seaside site. This must be dug up, and replaced with consistent material imported to the location by sea. This will require the construction of a temporary beach landing facility, one part of the planning proposal.

Material will also be arriving by rail, on trains with up to 20 wagons. These are up to 350 metres long, and carry about 1,250 tonnes each journey. With limited scope for trains to pass each other on the local East Suffolk railway, which is single track for many stretches, new rail infrastructure must be built. The UK is already building one major railway, HS2. While EDFconsidered some major changes to the existing line, they realised that UK rail agency Network Rail might struggle with another major project. So this task falls upon EDF and its partners.

“In most of the early years of the project, before the Sizewell Link Road and all the rest of the stuff is completed, we’ll be taking two trains a day into some new sidings we’re going to create just to the east of Leiston,” says Hicks. “Whilst we’re doing that, we’ll also be building something called the Green Rail Route, which is a four and a half kilometre long, private siding from the branch line, right into the construction site, to the concrete batching plant where the materials are needed.”

Getting heavy

The rail route will reduce the impact of HGVs on the roads, and assure EDF of reliable material supply. As well as these bulk materials, construction will require the movement of vast numbers of ‘Abnormal Indivisible Loads’, or AILs. These fall into two categories: permanent AILs, which will form part of the plant; and temporary AILs, such as cranes and TBM components, which will be used only during construction. Hicks expects around 400 permanent AILs will be delivered, largely in the final stages of construction, and around 750 temporary AILs each year. 

“About half of them are what are called construction and use wide loads,” says Hicks. “These are more than 2.9 metres wide, and therefore outside the normal regulations. They’re not particularly heavy, they’re just wide. And then you get increasingly heavy things called STGO loads, up to 50 tonnes, then up to 80 tonnes, and then up to 150 tonnes. They make up pretty well all of the rest of the 50%.

“And then you get very, very few, that are called special order VR 1 loads. And these are the exceptionally big things which are more than six metres wide, or more than 150 tonnes and these are the ones where they’ll try to transport them by the beach landing facility. But on some occasions you might not be able to do that, you have to do it by road. So they’re very rare. It’s probably a couple of those a year maybe.

Bringing all of these people, and all of this material, to site will require extensive use of road, rail, and sea infrastructure. 

Richard Bull is the head of DCO delivery for the project leading from the client side. He was involved in developing the transport proposals throughout the public consultation stages, and describes the existing infrastructure around the site.

“Sizewell itself is a challenging site. It’s serviced in the main by the A12, travelling from north to south or south to north. But the current main access route to the plant is via the B1122, which was the main access road for the construction of Sizewell B, and there are communities along that route, Theberton and Middleton Moor, and Yoxford, that that we have paid particular attention to, in developing our proposals for the DCO,” Bull explains.

“The application for the development consent order includes a number of transport schemes to reduce impacts on those B roads specifically, and the A 12 for example, bypassing certain local communities to reduce those transport impacts.”

Bull adds that EDF’s experience from Hinkley Point had demonstrated the need for appropriate infrastructure. And as part of the DCO application, EDF proposed enhancements to the infrastructure along the major route corridors used for materials, the A12, and B1122, along with the new rail and water routes.

“We focused on developing a capability to deliver materials by rail,” says Bull. “We’ve worked very closely with Network Rail throughout that process to establish what’s possible noting the fact that the Suffolk line is constrained by a single line north of Woodbridge and south of Saxmundham so the capacity for moving rail so moving moving materials by rail during the day whilst the passenger services operating is minimal, but there is potential to move materials overnight which is where we focused our attention.

“The Suffolk line is an operating railway. For us to use it overnight, it still will need some enhancements to some level crossings and signalling that we’re working with Network Rail on. The major work that Sizewell C will be undertaking is to enhance the Sizewell branch line, which hasn’t been used for the last couple of years, but has been used previously for taking materials in and out of Sizewell A, on the nuclear flask service.”

EDF aims to improve the line enough, and to build a new spur line, that will allow for up to five trains in and out of site. The first step will be to lift and relay track, before the new rail link is completed.

Alongside these improvements to road and rail infrastructure, two new facilities will be needed for marine transport. “There will be the MBIF, the Marine Bulk Import Facility, which will be specifically used to import construction materials and aggregates to the site, and they will be transported to the main point of use, using a conveyor system,” says Bull. “We also will be constructing a permanent beach landing facility, which will be used for the larger abnormal indivisible loads.”

Ducks in a row

The DCO process comes to a crunch at the examination stage. At this point, an appointed examination panel looks at every aspect of the project, over a six month period. Their report is then passed to the Secretary of State, who makes a final decision.

Before the examination clock started ticking, EDF and WSP needed to make sure they had a robust model in place that allowed them to answer stakeholders’ concerns, and examiners’ questions. This needed to address both transport of materials and AILs, and passenger transport.

“The project will have an impact on accommodation in the area,” says Hicks. “And one of the things that we did early on was we built what’s called a gravity model. And that’s looking at where people are likely to live, who are working on the site, and again, splitting it into the home based and non-home based workers. 

“We had some information from Sizewell B from the 1980s. And we tried to calibrate our model to reflect travel behaviour, at that time, and it was a little bit crude. But that’s the way that we tried to determine where people are likely to live whilst working on the site.”

This initial modelling and verification created a starting point for the planning process. The next step was to build a strategic model that could be used to see the impacts of Sizewell C construction worker and freight traffic around the region, using Visum.

“We then built a strategic traffic model that extends from Lowestoft in the north to Ipswich in the south, and about 35 kilometres inland,” says Hicks. “And we first use that to replicate what we see on the ground now, to calibrate the model, and show it reflects existing conditions. Only then can we use it to forecast what might happen in the future, when we introduce all these new workers going to Sizewell.”

The VISUM model allowed for a robust, accurate, model of impacts of each possible infrastructure plan. This responded to concerns raised by the examining authority at Hinkley Point, who had been disappointed by the spreadsheet model used in that application.

“It’s a huge undertaking,” says Hicks, noting that one of his colleagues, Sally Powell, spent the better part of ten years on the project, “But it’s really important because it gives us the information to assess where the impacts are, and not only from a transport perspective. We also use that information to assess changes in air quality, changes in the noise environment, andinforms a lot of the environmental assessment that we do as well.”

John had joined the project in the middle of his career. While he has taken on some smaller, but still significant, projects in this time, Sizewell has dominated his working life for more than a decade. As the examination stage of the process loomed, he handed over the reins to Nick Cottman. 

“The Planning Act of 2008 brought in new procedures around nationally important infrastructure,” says Cottman. “It created a new consenting process called the development consent order (DCO) process that put strict timescales on the overall application and examination process to get to a decision. It certainly focuses everyone’s mind to work towards reaching a decision.

“Although the timescales are tightly constrained, it is really all configured around the stakeholders having an opportunity to influence the process and the proposals and for them to be scrutinised in an appropriate way.”

The Examining Authority consisted of five members, from a variety of backgrounds. One of the examiners paid particularly close attention to the impact of the project on vehicle mileage. EDF had considered five potential routes for the new Sizewell Link Road that would bypass the B1122, reducing disruption to local communities.

“We determined that we needed to effectively bypass the B1122 to reduce the traffic volume on it,” says Hicks. “We came up with various alternatives, and looked at what the highway geometry standard required us to do. Then we did what’s called a multicriteria assessment of the five routes. And that looked at, for example, ‘land take’, the length of the scheme, the impact on drainage, the impact on the number of landowners affected, the need to cross rivers, or the railway in this particular case, and a whole host of other stuff.

“We had five routes, and there were some of them that, once we did the multicriteria assessment, really weren’t going to be the winner. So once we’d narrowed it down a bit, we started to look at using the model to try and predict what the traffic effect of the route would be. And what we found fairly quickly, was that the northern route, which is the one that we eventually picked, was by far the most effective at reducing traffic on the B1122.”

But this route did not reduce vehicle mileage as much as some of the other routes, and so drew questions from the examiner. WSP’s model was able to help EDF show that it was still the best option.

“We persuaded the examining authority that the route that we had chosen was the right one, it didn’t minimise mileage,” says Hicks. “But it was the most effective in reducing the impact on the B1122, which was the reason in the first place that we wanted to build a Sizewell Link Road”. 

A key way of minimising impacts on the communities around Sizewell is through the adoption of a Construction Traffic Management Plan (produced by WSP) and a Delivery Management System (developed by EDF). This will see HGVs, or Heavy Goods Vehicles, corralled at a Freight Management Facility close to the A12. They will then travel on a closely planned schedule, so material arrives at site when needed, without causing congestion or disruption on the B1122.

It is complemented by two Park & Ride schemes, which will allow workers driving to the site from farther away to park at two locations, north and south of the site, and complete their journey by bus.

The impact of these measures will be monitored as work progresses, allowing stakeholders and authorities to ensure the plan is being implemented properly.

Meeting the requirements of the DCO process has taken years of work from Bull, Hicks, and Cottman, as well as colleagues like Powell. But, Cottman says, it has proven worthwhile, and acts as a model for how projects of this scale are planned and approved, around the world. With some adjustments, it could also be an efficient way to plan and approve smaller, but still nationally significant, projects.

“The DCO process certainly supports the timescales required to reach decisions about nationally important infrastructure,” says Cottman. “And from that point of view, I think it would be seen as a success there, and a process that supports those outcomes. 

“There has been a lot of discussion recently in the media and within government, about the efficiency of the process and the timescales required for various different projects and, of course, DCOs, although they’re all nationally significant infrastructure, they all vary in size, but are all constrained to the same strict timescale. So there is some waiting on an announcement from the government around opportunities to streamline the process. So we may see some further changes coming to the DCO process in the near future. 

“But a real strength of DCO is that at the end of the process, the applicant has an all encompassing consent to move forward with the development that incorporates all of the land acquisition rights, all of the consenting rights, the planning, consenting rights, various orders that are wrapped into the DCO process, so that it is a sort of a one-stop-shop or an all encompassing consent to move forward.”