Rail bosses are looking to nearly double the size of a station car park.
Network Rail has applied to build a three-deck car park over the current car park in Haywards Heath Railway Station. The extension would see the station car park capacity increase from 600 parking spaces to 1,087.
The rail authority had previously obtained permission for a single-storey addition to the car park to provide 120 spaces but following further consideration has decided to increase the expansion further.
Rail bosses say the change is necessary because of an increase in demand for rail travel which means that many station car parks are reaching capacity.
Increasing the total number of car parking spaces available is a franchise commitment for Southern from the Department for Transport.
The proposed model is a demountable modular steel framed car park structure above the existing main car park which is recognised as a fast construction method, aimed at keeping the impact to the local environment to the minimum.
Earlier this month, plans for a multi-million- pound redevelopment of the railway station cleared a major obstacle after it was revealed that Eric Pickles, the Secretary of State for Local Government, will not call in the decision.
The project would see land off Market Place used for a new 4,122 sq m Waitrose supermarket and 754 sq m of retail and restaurant space.
A public consultation in May last year had more than 1,100 responses, with 94 per cent of those saying they supported the plans.
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