Whenever the legislative body of any municipality shall determine that it is necessary to acquire, open or widen any boulevard, street or alley within said municipality, and whenever such legislative body shall determine that in order to carry out such proposed improvement most advantageously that it is necessary to take private property adjacent to the proposed improvement, the fee to such private property may be purchased or taken by condemnation proceedings and the taking of such private property for the purpose of advantageously carrying out the proposed improvement contemplated is hereby declared to be a taking for a public purpose.