23 CFR § 650.103 - Policy.
It is the policy of the FHWA:
(a) To encourage a broad and unified effort to prevent uneconomic, hazardous or incompatible use and development of the Nation's flood plains,
(b) To avoid longitudinal encroachments, where practicable,
(c) To avoid significant encroachments, where practicable,
(f) To avoid support of incompatible flood-plain development,
(g) To be consistent with the intent of the Standards and Criteria of the National Flood Insurance Program, where appropriate, and
(h) To incorporate “A Unified National Program for Floodplain Management” of the Water Resources Council into FHWA procedures.