PHOTO: The site at Kemps Creek, which is the largest out of the three, could sell for triple its last sale price two years ago. Photo: Supplied

Three families could reap about $50 million after listing nearly 40 hectares of land near the future Western Sydney Airport.

The three assets – in Luddenham, Kemps Creek and Badgerys Creek – are being sold separately and are all owned by families living on the properties.

The average land rate for the three sites is about $1.3 million a hectare.

The 17.4 hectare property at 752-810 Luddenham Road, Luddenham, is tipped to sell for more than $20 million, according to market sources. It last sold for $1.15 million in 2002, Domain Group data shows.