; and (ii) may not carry out the project until Congress authorizes the construction of the project. (C) Demolition Demolition of a temporary structure under this section shall be subject to the cost-share requirement under paragraph (3), but the costs of that demolition shall not be included in the total construction cost of the project under subparagraphs (A) and (B). (3) Cost-share (A) In general Except as provided in subparagraph (B), the non-Federal share of the cost of carrying out a project under this section shall be not more than 35 percent. (B) Waiver for small or disadvantaged communities In carrying out a project under this section in partnership with a small or disadvantaged community, if the Secretary determines that the life safety or economic viability of the community would be threatened without the project, the Secretary shall reduce the non-Federal cost share applicable to the project through a mutual agreement between the Corps of Engineers and the non-Federal interest, in an amount that is— (i) not less than 10 percent of the total project cost; and (ii) up to 100 percent of the non-Federal cost share applicable to the project. 1054. Studies of water resources development projects by non-Federal interests Section 203 of the Water Resources Development Act of 1986 ( 33 U.S.C. 2231 ) is amended— (1) in subsection (a)— (A) in paragraph (1), by inserting or conduct a feasibility study on modifications or improvements to a project constructed by the Corps of Engineers after water resources development project ; and (B) in paragraph (2), by striking for feasibility studies and all that follows through the period at the end and inserting for feasibility studies of water resources development projects conducted by non-Federal interests to provide sufficient information for the formulation of the studies, including processes and procedures related to reviews and assistance under subsection (e).