A rail tack operator has been accused of wasting £1.5million on a “monster” of a bridge at a west Suffolk cycle route which a sustainable transport charity felt was already safe.

Network Rail’s ramped bridleway bridge at Heath Road, just outside Thurston and near Bury St Edmunds, has been described as a “green monster” and “a total waste of money”.

Sustrans had objected to the planning application, which was approved by St Edmundsbury Borough Council, on the grounds that it made the route less attractive and convenient for cyclists, walkers and horse riders.

Due to open at the beginning of next month, the bridge is part of Network Rail’s programme to improve level crossing safety.

Anthony Wright, Sustrans area manger for Suffolk, said: “In Sustrans’ opinion the crossing is safe and it’s up to the users to actually make sure they respond to the instructions that are given to them [referring to signage at the crossing].”

Mr Wright did acknowledge the bridge would make cycle route 51 even safer, but added it would also be longer.

Locals did not dispute safety is paramount, but believe the new piece of infrastructure is completely unnecessary and out of proportion.

Nigel Rhodes, 65, a former headteacher, described it as a “monstrosity”.

He said: “They have built what I call a green monster really. It’s painted green. It is huge, absolutely huge. I understand the argument ‘what price is a life’ but there is a point where you think ‘hang on a minute, it’s just over the top completely’.”

Mid Suffolk District Councillor Derrick Haley, who lives in Thurston and represents the village, said he was “astounded” by the bridge.

“It’s a waste of money. All they needed to do was put lights and lockable gates; that’s what people would have accepted without any problem.”

He added: “I don’t want to see this in the countryside.”

The Network Rail spokeswoman said the bridge was so big due to the fully accessible ramps, which can accommodate horse riders, yet locals say they have never seen horse riders use the route.

She said the crossing was also a bridleway so access had to be maintained, but added everyone would be able to use it, including people with pushchairs.

A number of residents also said they have no knowledge of there ever being an accident at the level crossing – known as the Great Barton crossing – however Network Rail said there was a reported near-miss in 2012.

The spokeswoman added: “Great Barton level crossing was selected for closure primarily owing to the frequency of use, and the fact that it’s on a cycle route often used by tourists. It cuts across a busy train route.”

Thurston resident Des Kelly, a volunteer ranger for that part of the cycleway with Sustrans, said: “It’s just a joke really. It’s all far too late. I have been telling anyone who will listen it’s called a boondoggle.

“It’s a project that’s totally useless and wasteful and it’s done by corporate people who are far away.”

Network Rail has effectively been renationalised, with its £32billion net debt shifted on to the Treasury’s books.