In 1974 , under the Local Government Act 1972 , Staines Urban District was abolished .
Staines Urban District 's area combined with that of Sunbury - on - Thames Urban District to create the present borough of Spelthorne .
In 1974 , under the Local Government Act 1972 , Staines Urban District was abolished and its area combined with that of Sunbury - on - Thames Urban District to create the present borough of Spelthorne .