She said villagers faced a six or seven mile detour to get round the village while the level crossing was closed.
The shortest route: using the level crossing – 2 miles
A council spokesman said “a detrimental impact on the character and setting of the listed signal box and main station building”.
The council added replacing the crossing would cause “substantial harm to the significance of the signal box”, and the loss of the original gates would outweigh the public benefits.
Had the planned work gone ahead, the road would have reopened by the 12th October Network Rail said that it was now “unachievable”.
Alternative number one – 7.3 miles
Meanwhile 600 people have signed a petition calling for the crossing to be restored, because while it is blocked local motorists are forced to take a diversion of some 7 miles.
The firm is now seeking an extension to the road closure which has been in place since 25 September.
Local MP Ms Caulfield said: “‘It is vital that the road through Plumpton, which include the level crossing is opened straightaway.
Alternative number two – 5.2 miles
“It is completely unreasonable to ask local people to undertake lengthy journeys to simply get around the village.”
Network Rail area director Steve Knight admitted that they had been wrong to assume that planning permission would be granted, but said: “We sincerely apologise to local residents for the disruption caused by the current closure of Plumpton level crossing.
No level crossing is entirely safe or risk free, but we know we have to find a safer long term solution for the level crossing at Plumpton. We cannot stand idly by and allow an outdated, high-risk crossing to remain in use when we know we can make it much safer.”
In its letter to residents, Network Rail warned that an early solution seems unlikely. It explained: “We are working round the clock to try and find a temporary safe solution for the level crossing that is acceptable to residents and the local community and meets our obligations. However, this will take us some time and it is likely that the current diversionary routes will remain for at least the next three months.