Eurotunnel has declared itself ready for a no-deal Brexit as it unveiled £13m of new infrastructure, including passport controls and additional border inspection posts in Calais.

After two years of preparations, often in the absence of any government direction, and the millions of pounds spent on plans that may never be implemented, its parent company Getlink said it was “ready no matter what”.

At the launch of the additions to its 650-hectare (1,606-acre) commercial fortress in Calais, the company said it believed it would be able to guarantee no extra delays on traffic going through the tunnel into the UK.

And it hopes its new infrastructure combined with more staff will mean the mandatory animal health checks needed by the EU can be easily accommodated.

Eurotunnel’s new infrastructure in Calais showing green and orange routes. The orange route is for those needing customs checks. Photograph: Sean Smith/The Guardian

“We do not expect any delays. We are ready. This preparation is for the worst case of no deal so that in that instance the traffic continues to flow through at the same rate as it does now,” said John Keefe, the director of public affairs at Getlink.

Under a £20m no-deal contingency plan implemented by the French government in January, the Eurotunnel site in Calais has been designated the official EU border inspection post for horses and other large animals.

It is part of a jigsaw of checks on the French side of the Channel, with British fish due to being examined in nearby Boulogne and other fresh food a few kilometres away at a third inspection post near Calais port.

At the moment horses can travel freely between the three racing nations of France, Britain and Ireland as long as they have a passport and an intra-trade animal health certificate.

In the event of a no-deal Brexit a newly built border inspection post awaits for all racehorses and bloodstock to be physically checked in at Calais. Stables for queues of up to 20 horses are expected to be completed in the coming days.

The checks will be mandatory to guard against the spread of disease such as the recent outbreak of equine flu, which caused the cancellation of horse races in Britain.

The French authorities have been performing dry runs for customs declarations and on Thursday security staff were out in force stamping specimen customs declarations forms.

As the British government has already said it will not be conducting any checks on goods coming into the UK, these rehearsals remain academic, but part of the meticulous planning in motion for a no-deal Brexit in France.

In the event all runs smoothly in Dover, the key risk for British business is expected to centre on animal and food exports, which will be subject to mandatory controls for disease and pests. This means 100% documentary checks on animals and physical checks for 20% of beef, pork and lamb, and 50% of poultry.

As well as the new infrastructure, Eurotunnel also unveiled “green and orange” routes for entry into France and the EU.

Eurotunnel says it has space for 100 trucks to be parked for checks, which is 50% of its hourly traffic. Photograph: Sean Smith/The Guardian

Those requiring checks will be directed on the orange route towards a border control zone involving customs, sanitary and phytosanitary checks featuring nine bays, where a truck can be fully unloaded in secure and temperature-controlled warehousing.

“We have space for 100 trucks to be parked, 50% of our hourly traffic, and that’s way more than the authorities say they need,” said Keefe. “We’ve spent €15m on new buildings, warehousing, e-gates for passport checks, cameras, scanners, roads and signage.”

Thursday was not a typical day for Eurotunnel traffic flow, with a French customs work-to-rule protest causing 23 miles of queues from Calais to the Belgian border.

The work to rule strike has been disrupting traffic for three weeks, causing delays of up to six hours. Tempers were frayed as drivers waited for security checks.

“Brexit will be the death of the UK,” declared one French driver as he waited at the “pit stop”, where 20 heavy goods vehicles at a time were stopped to be checked by dogs straining at their leashes as they sniffed for stowaways.

Although the delays are not related to Brexit, they illustrate the potential impact of disruption and the risk posed by a no-deal scenario if all does not go as smoothly as everyone on the French side of the border intends.