Controversial plans to move Warwick Castle's overflow car park closer to neighbouring homes has been approved after it was explained that the decision would bring about heritage benefits.

The decision will see the existing site on the banks of the River Avon returned to pasture and an adjacent field away from the flood plain utilised with up to 1,200 cars parking there. A wooded area known as The Lilacs, which varies between 60 and 100 metres wide, sits between the site and houses in Foxes Way and Leyfields Crescent.

Planning officer Lucy Hammond told this week's meeting of Warwick District Council's planning committee that gravel tracks on the current overflow car park would be removed and that there were no plans for permanent lighting to be installed although temporary lights could be brought in during the winter months. 

She also explained that the old carriage drive – a historic feature – would be revealed, adding: "It is about moving the car park out of the flood plain and into an area where there are improvements to be gained. It is certainly not my understanding that there is any intention that this will be used in a permanent capacity of any description."

More than 125 letters of objection were sent to the council and a number of residents spoke against the plans at the meeting.

Dr Christine Hodgetts, representing the Conservation Advisory Forum, explained how important the castle grounds were.

She said: "Gardens of this importance are scarce and sustainable to damage and planning authorities are obliged to protect them. While acknowledging that this proposal is better than the existing, it is not good enough to render it acceptable.

"Leafields and its cars are not only visible from the hunting lodge but also from the circuit of the drive as it descends Lodge Hill, crosses Leafield Bridge and advances over the level grounds of Leafields towards the castle."

Other speakers raised concerns about bats and badgers and the worries of those living near the site which would continue to be accessed from the castle entrance off Stratford Road.

Neighbour David Bennett said: "We feel repulsed by the idea of a massive car park behind us. We really need to rethink this proposal. It is not enough to tweak it – this is going to be a major change."

Nick Blofeld, Warwick Castle's divisional director, said he believed the relocation would deliver significant benefits for heritage, the landscape and ecology.

Councillors voted unanimously in favour of the plans.