Use. Except as set forth in 774.11 and 774.13, a use of Section 4 property occurs:
(1) When land is permanently incorporated into a transportation facility;
(2) When there is a temporary occupancy of land that is adverse in terms of the statute's preservation purpose as determined by the criteria in § 774.13(d); or
(3) When there is a constructive use of a Section 4(f) property as determined by the criteria in § 774.15.
23 CFR § 774.17
The definitions contained in 23 U.S.C. 101 are applicable to this part. In addition, the following definitions apply: