In order to encourage the building of bridges, causeways and other development work and relief work, the owner of any lands in the State of Alabama abutting on tidelands, the title to which or control of which may now or hereafter be vested in the State of Alabama, which shall not have been improved by or under valid public authority and shall not be otherwise devoted to public use, shall be authorized to acquire such tidelands and to fill, reclaim or otherwise improve same and to fill in, reclaim or otherwise improve the abutting submerged land and to own, use, mortgage and convey the lands so reclaimed, filled or improved, and any improvements thereon, under and subject to the conditions and approval herein stated.

Any such improvement shall conform to any harbor line established at the time of such improvement by state or federal authority having jurisdiction over such matters, or if not then already established, same shall conform to any harbor line stipulated by any such authority having jurisdiction on application by such riparian owner.

If such land shall be used for a bridge, road or causeway over navigable waters, or for bridgehead or approach thereto or for terminal facilities, depots, storage or sale yards, stores, warehouses or wharves abutting on such bridge or road or causeway, the plans for such bridge, road or causeway shall be approved by the United States engineer officers or other federal authority having jurisdiction, and by the director of the State Docks Department and the Governor of Alabama, and when so approved and when improved pursuant to such approval the title to the said lands and the entire improvements thereon shall vest in such riparian owner without further approval when the bridge, road or causeway shall be constructed pursuant to the plans so approved.

If such improvement constructed or proposed shall not consist of a bridge, bridgehead, road or causeway, approach or related improvement included within this section, title shall not pass to the riparian owner making or proposing such improvement unless and until the riparian owner shall have obtained the approval of the county commission of the county in which the land is situated, and of the director of the State Docks Department and the Governor of Alabama, on application of such owner made after publication of 10 days' notice thereof by a single publication in a newspaper published in the county in which the land is situated and shall have filed for record in the county a certificate of such approval executed and acknowledged by the presiding officer of said respective authorities.