Nearly 150 of the country’s most protected amphibians have been found at a water mains construction site near Detling.

Seemingly undeterred by the nearby M20 and high speed railway line, the population of great crested newts came as a “huge shock” to ecologists at South East Water, who discovered them while a pipeline was installed in Horish Woods.

More than 3,500 newts were found overall ahead of laying the new £330,000 water main.

Among them were 148 great crested newts, 15 cm long critters which are legally protected and cannot be disturbed without obtaining a special licence.

Environmental clerk of works at South East Water, Mandy Apps, said: “Horish Woods near Detling is not an area where you would expect to find such large numbers of newts, especially given the low numbers evident in the pre-works survey.

“With the habitat split by the M20 and rail link, combined with motorway run off which drains into the only pond on site, means that it’s been a surprise to find so many living here.

“In fact, this area has been the most prolific site we have ever had for newts which is a huge shock.”

In August 2013, three months before work began, special newt fencing and bucket traps were placed at 10 metre intervals.

The newts have been temporarily removed from the site by licensed experts while works continue.

The new pipeline, 250 metres in length, is needed to replace an old water main to improve the flow of water between a borehole near Harple Lane and water treatment works in Detling. It is due to be completed in Spring 2014.