Central coast residents have launched a scathing attack on the New South Wales Government over what they said was a blatant disregard for the environment after recent works has seen tonnes of silt, clay and rocks wash into Bangalow Creek, renowned for its wildlife.

Kangy Angy locals are furious at the extent of environmental damage being done by the $300 million New Intercity Fleet Program Maintenance Facility development, stating it was far worse than what they ever expected.

Paul Taylor, who has been cut off from 10 acres of his family farm said the waterways were home to platypus, bass, eels, crayfish and native flora and fauna.

"Everything has an effect once you start bringing in bulldozers and excavators," he said.

"You only need to take a look at the Darling River, what's happening there.

"We need to take greater management of our river systems because they are very fragile."

Mr Taylor said the current siltation traps and retention ponds in place are not working.

"They're pretty much not adequate for the higher rainfall that we get in this area," he said.

"They say they want to pull tourists from Sydney up to enjoy our pristine environment. Well who's going to want to come up here and see what we've created. We've created a mess."

Resident Paul Taylor is disappointed in the State Government's lack of action to save the environment around his home. ( ABC News: Meghna Bali )

In a statement, Scott MacDonald, Parliamentary Secretary for Planning on the Central Coast said the matter had been investigated.

"Transport for NSW takes our commitment to minimising our impact on the local environment very seriously," it read.

"Prior to the major rain event on 28 November 2018, the contractor John Holland, completed inspections to ensure that the erosion and sediment controls were installed in accordance with best practice guidelines.

"Following the storm, the erosion and sediment controls were inspected and repaired where needed."

A controversial history

Aerial artist's impression of the maintenance facility looking east. ( Supplied: Transport for NSW )

Kangy Angy did not originally appear on the list of 24 sites considered by the State Government in 2015 and was only selected after being floated as an alternative by the former Wyong Council who did not wish to approve the sale of the land at the preferred site in Warnervale.

But the site was ultimately chosen because of its proximity to the rail line.

The facility will service and maintain the new fleet of trains carrying people from Sydney to the Central Coast, Newcastle, the Blue Mountains and the South Coast.

This involves constructing various buildings and around six kilometres of electrified railway, up to seven tracks wide and covering half a million square metres of land.

Damage to environment

Last year protestors tried to stop trees from being chopped down on Orchard Road, a well known habitat for endangered birds. ( Supplied: Train Maintenance Facility Residents Action Group )

Tracey Stewart from the Kangy Angy Residents Action Group said they have opposed every step of the development.

The group had questioned the legitimacy of using the semi-rural land, citing issues regarding inaccessible flood-prone land and the environmental impact.

The area is home to the foraging habitats of two critically endangered birds — the Regent Honeyeater and Swift Parrot.

Ms Stewart said the birds had not been seen since construction began in 2017.

"And we probably never will again because the destruction has been so widespread," she said.

Ms Stewart wrote to contractor John Holland's office asking if a platypus survey had been conducted of local waterways.

"They told us that they didn't need to, they wouldn't be affecting their habitat area," she said.

"How can these animals have a regular food source with the absolute woeful condition of creeks?"

Ms Stewart said the residents were frustrated their concerns were falling on deaf ears.

"The government is a law unto itself, they have no concern about the environment, all the warnings they were given before are all coming into fruition now," she said.

Paradise lost

Paul Taylor always knew the development was going to be bad, but he said this was beyond his worst nightmare.

"It really is heartbreaking," he said.

Mr Taylor said the land had been in his family for decades and remembered it as a sanctuary.

"My dad used to sit on his rocking chair and he'd say … 'we're the luckiest people in the world', and he was right, but now we're the unluckiest people because the government's come knocking on our door and what they've left is just destruction of the environment and our way of life," he said.

State Environment Minister Gabrielle Upton would not comment on the matter as she said it was outside her portfolio.

Transport Minister Andrew Constance declined to comment.