It has been a year since work began on revamping one of Kent's busiest motorway junctions. But what happens on the other side of the barriers?

Senior reporter John Nurden donned his hard hat and headed for the M2 and A249 Stockbury roundabout to find out.

The first person you meet as you enter National Highways' compound at Stockbury near Sittingbourne is Ahmed Ali.

He is there every day, rain or shine, to welcome visitors to Graham's construction site. And he does a marvellous job.

"Good morning sir, my name is Ali," he says, smiling and proudly pointing to his name badge. As he takes down your particulars he also ensures you see a price list for the burger van in the car park. The man has his priorities right.

The other thing you notice is that the construction team are in for the long haul. They have built a three-storey office block out of portable cabins to house all the essentials needed for working in all kinds of weather, often many miles from home.

There is a natty boot-washing contraption with a hosepipe outside to ensure the inside remains clean. There is a canteen, changing rooms, showers, toilets and offices.

It has been a year since work began on building the £92m flyover across the notoriously busy roundabout.

Planners believe it will ease rush-hour traffic jams of vehicles heading between Maidstone and Sheppey and joining the M2 at junction 5, although if you believe social media, all that was really needed was to turn the traffic lights off.

Making sure it all goes to plan is 34-year-old Dan Rollinson from Doncaster. He is National Highways' project manager and the buck stops on his desk.

Interestingly, he's not an engineer but a business management graduate who cut his teeth running events in London and launching the Shoosh nightclub on Brighton beach. "I was looking for a career to use my transferable skills and project management seemed a good choice," he said. "Time spent on nightclub doors has held me in good stead for dealing with the public."

This is his first job in the hot seat although he's also worked on the M20 scheme at Ashford and the A2 operation at Blean and Ebbsfleet.

He said: "Some schemes are more complex than others but this falls somewhere in the middle. Every project has its own difficulties. It is my job to help ensure it all comes together."

The other man at the sharp end is Stevie Collins, 42. He is Dan's opposite number at Graham, the construction company tasked with the actual building work. It is the first time he has had to work with chalk. "Chalk is very susceptible to the weather," he explained. "When it's dry, it's fantastic. When it's wet it gives us lots of challenges."

During the exceptional hot, dry summer, earth-moving work raced ahead of schedule as excavators removed whole hillsides and a fleet of dumper trucks carried the spoil to Honeycrock Hill for storing and recycling. Old road surfaces and chunks of unearthed concrete have been crushed and used to surface the compound's car park.

Dan said: "Everything is recycled where possible. Even the offices were taken from another site."

When the project finishes early 2024 it will be left with a surplus of 250,000 cubic metres (that's half a million tonnes) of material. But even that is being re-used. It is being shipped to Sheppey where part of Queenborough is being raised to make an estate of new houses flood-proof.

Many residents expressed concerns when the diggers first arrived in Stockbury and began ripping up trees and undergrowth to make way for the new roads. But Stevie stressed: "It was all closely monitored. We had ecologists on site to ensure no wildlife was harmed. We have relocated ancient hedgerows, saved rare orchids and installed bat boxes."

Archaeologists also had the run of five locations. They were looking for Second World War trenches and even found fragments from a Roman furnace. Stevie said: "Nothing of significance was discovered, otherwise we wouldn't be here."

Gareth Howe, 59, is from Maidstone and has the task of signing everything off. He said: "This is a great job for me. It's only the second time I have worked where I've been able to go home at night. Normally, I end up spending two years in places like Manchester, Birmingham or Cornwall."

The former St Simon Stock Catholic School pupil said: "Construction work has changed an awful lot since I started 40 years ago. In the 1980s, people relied on the experience of the supervisors. And if you were told to do something you had to do it. There were no excuses.

"These days there are many more stringent health and safety rules. If you are asked to do something you don't think is safe, you don't have to do it."

Making sure the rules are followed is Chris Payne from Rochester. He is the health and safety guru.

He said: "I originally wanted to join the army but I had a health issue so I went into security and ended up working on the 2012 London Olympics in Stratford. I saw how important how health and safety was so I took self-study courses and have worked my way up."

Everyone on the site – there were 62 on the day of our visit – has to undergo an induction session and be kitted out with protective clothing. That includes the obligatory hard hat, steel-capped boots, hi-vis jackets and trousers and gloves. Vehicles are limited to 10mph.

Alcohol, drugs, horseplay, shouting, whistling and mobile phones are banned. The compound has its own heart defibrillator.

The weather, of course, plays an important part in keeping everything on time. When Storm Eunice hit in February, planned work to move power cables had to be postponed while UK Power Networks engineers were deployed to repair broken electricity lines across the county.

And work on moving a water main was delayed when Southern Water had to divert crews to tackle the water shortage on Sheppey in July.

Dan said: "We get some comments saying they can't see anything going on but that is not the case. It is a large site. There are also times when we are pouring concrete. We have to wait until it cures before we can go back to finish the job."

The flyover will arrive in three sections and will be craned into position probably during the middle of next year. At the moment, work building the new slip roads is taking precedence.

Dan said: "We want all the slip roads completed so the traffic can use them while we are working on the flyover. It should cause less problems."

He also revealed: "The sides of flyover will be faced in flint. The Kent Downs recommended it during talks because Stockbury Valley is an area of outstanding natural beauty. We had a number of test panels made up and a design has been picked."

To prepare for the flyover, 560 piles have been sunk beneath the M2 viaduct. To spread the load over the viaduct's existing foundations, a special flexi-arched bridge, a sort of giant flat-pack, has been installed.

Dan explained: "It is the largest of its kind in England. Each arch is made of 15 lines of 33 pre-cast concrete connected blocks. They all arrived on the back of lorries. When they were craned into position they opened up and formed the arches."

Some detractors have asked why the coast-bound exit and entry slips will remain closed until January. Dan is adamant that in the long run it will save time.

He said: "Without closing them, the work would have taken 46 weeks and would have needed 25 changes with traffic using dangerously narrow lanes. This way, we will be able to complete it in 18 weeks. It will be a lot safer for the travelling public and the workforce."

The project is also proving a great training ground for up and coming professionals.

Matt Barnett, 19, is an apprentice project manager. He said: "My dad is a civil engineer and I wanted to follow in his footsteps. I enjoy problem solving but I didn't want to go to university. This is great. And I don't mind getting dirty out on site."

Others coming through include 20-year-old Lucy Turnbull from Worcester who is studying engineering design at Bristol University. She was getting practical help from tutor Paul Clarkson as she learned to get to grips with the modern equivalent of the theodolite.

Paul said: "It's all very well building bridges but you can't put them in the right place without the skills of a surveyor."

Dan added: "They are very important. These bridges are measured to the millimetre. It is essential every measurement is exact."

It's good to know our roads are in safe hands.

For the latest construction news click here. See our latest drone photos of the site here.

Meet the construction team on Wednesday, November 9, at Oad Street Food and Crafts, Oad Street, Borden, ME9 8LB, 10am to noon and 5pm - 7pm. Or call 0300 123 5000.