The authority granted the State Highway Commission under provisions of this chapter, shall include the right to enter into agreements with the United States government, or any agency thereof, for the alteration, relocation, reconstruction, or abandonment of state highways or any portion thereof, and conveyance of whatever rights and interests the state owns in property acquired for the purposes of said statutes, or any portion or interest thereof, where the same are necessary for the construction of flood control, navigation, drainage, or National Aeronautics and Space Agency projects approved and adopted by the United States government or any agency thereof.

Upon proper authorization by the State Highway Commission, the director of the State Highway Department is hereby empowered to execute a quitclaim deed selling and conveying the above rights and interests. Said deed shall be delivered to the purchaser upon the payment of the consideration agreed upon, and such consideration shall be deposited in the State Treasury to the credit of the State Highway Fund.

Such agreements and conveyances shall be upon a consideration deemed reasonable by the State Highway Commission and the agency of the United States government affected, provided that no part of this section is intended to alter or change in any way the existing immunity from certain actions of the state or the United States.

The consideration above shall include the expense of creating and maintaining any necessary detours, and the same shall be created and maintained as provided in the above mentioned agreement.