The Secretary of the Army is authorized to investigate, study, plan, and implement structural and nonstructural measures for the prevention or mitigation of shore damages attributable to Federal navigation works and shore damage attributable to the Atlantic Intracoastal Waterway and the Gulf Intracoastal Waterway, if a non-Federal public body agrees to operate and maintain such measures, and, in the case of interests in real property acquired in conjunction with nonstructural measures, to operate and maintain the property for public purposes in accordance with regulations prescribed by the Secretary.

The costs of implementing measures, including a study, shall be cost-shared in the same proportion as the cost-sharing provisions applicable to construction of the project causing the shore damage.

No such project shall be initiated without specific authorization by Congress if the Federal first cost exceeds $15,000,000.

Beginning on December 16, 2016, in any case in which the Secretary implements a project under this section, the Secretary shall reimburse or credit the non-Federal interest for any amounts contributed for the study evaluating the damage in excess of the non-Federal share of the costs, as determined under subsection (b).