The veteran environmental campaigner known as Swampy and a group of other anti-HS2 protesters cost the company building the high-speed railway line £3.5 million by tunnelling under the development.
The loss was revealed as Daniel Hooper, 48, also known as “Swampy”, Dr Larch Maxey, 49, Isla Sandford, 18, Lachlan Sandford, 20, Juliett Stevenson-Clarke, 22 and Scott Green went on trial for offences linked to tunnels and treehouses they created in January this year.
The six, all part of a group called HS2 Rebellion, dug tunnels underneath Euston Square in north London and lived inside them for a month to protest against the building of the railway line, their trial at Highbury Magistrates’ Court heard on Tuesday.
They all deny obstructing or disrupting a person engaged in lawful activity, and Dr Maxey also denies a charge of criminal damage of a mobile phone.
The court heard that the six defendants occupied the tunnel system and treehouses they had built from pallets, and then branded “Buckingham Pallets”, in protest over the HS2 redevelopment of the area.
Prosecutor Sarah Gaby told the court HS2 possessed the area and contractors were due to start work in Euston Square before the discovery of the secret network of tunnels on January 26 this year.
Two days later, HS2 issued a warrant ordering protesters off the site.
On February 19, a High Court injunction ruled the group were to stop further tunnelling and tell HS2, the Health and Safety Executive, London Fire Brigade and the police how many people were in the tunnels. The last did not leave for another month on February 26.
The court heard from Simon Natas, a chartered surveyor at HS2, who said the protesters had cost the company – which had arranged contractors to build a new taxi rank at the station – £3.5 million.
He said an estimated £2.8 million was spent on enforcement officers tasked with removing the protesters from the site.
The surveyor told of a dawn raid on the protest site at around 4.15am on January 27, that had the aim of removing the protesters.
He said: “I saw the lid of a tunnel and there were three tree platforms and tents. Most of them were escorted by enforcement officers.”
Specialist enforcement officer Brett Easter told the court he was tasked with removing the protesters from enclosed spaces, including the tunnels.
He said this included the creation of nine underground “drop shafts” that would create a “cat and mouse” game with protesters, who then left the tunnels over the course over the month.
Mr Easter said he was also charged with the task of checking on the wellbeing and safety of the protesters who were living inside the tunnels, and said paramedics were on hand to help if they were needed.
He said: “We forced entry through a metal door and when we were inside we gave another warning in regards to the warrant. The tunnel was secured with pallets and filled with spoil after they had dug the tunnels so we had to deconstruct that, taking time to make sure we didn’t undermine the structure of the buildings [tunnels].”
Mr Easter said enforcement officers used an endoscopic camera to see where the protesters had dug the 10-foot tunnels.
He said: “The tunnels were a body’s width, at some points there were chambers which would be used as storage for food, or a place they could rest and plan.”
The trial is expected to run until Friday.