; and (4) additional available hydrologic and hydraulic data from public and private sources regarding current and future flood risk, including information on expected changes in precipitation patterns, erosion, and sea level. (c) Alternate design levels for resilient infrastructure If, after considering the available information required under subsection (b), the head of an agency determines that such information is not adequate or sufficiently credible to understand and characterize current and future flood risks to the project, the head of the agency shall use the following design standards in evaluating resilience for or alternatives to the investment: (1) Non-critical projects If the project under review is not considered critical, the head of the agency shall assume, at a minimum, that flood heights would be expected to be 2 feet higher than the base flood elevation for the current 1 percent annual chance flood or the flood elevation for the current 0.2 percent annual chance flood, whichever is greater. (2) Critical projects If the project under review is considered critical, the head of the agency shall assume, at a minimum, that flood heights would be expected to be 3 feet higher than the base flood elevation for the current 1 percent annual chance flood or 1 foot higher than the flood elevation for the current 0.2 percent annual chance flood, whichever is greater. (3) Resilience standard In evaluating resilience options, the flood heights specified in preceding paragraphs shall establish a standard design level to which a structure or facility evaluated under this subsection shall be made functionally resilient. This may include using structural or nonstructural methods to reduce or prevent damage, elevating a structure, or where appropriate, designing it to adapt to, withstand, and rapidly recover from the corresponding flood event. (4) Alternatives In evaluating alternatives, including alternative sites and designs, the head of the agency shall fully consider the ability of natural systems and