43 CFR § 423.14
How will Reclamation post and delineate closed areas at the site of the closure?
June 11, 2020
Before or at the time of closing all or portions of Reclamation facilities, lands, or waterbodies to public use, the responsible authorized official must indicate the closure by:
(a) Locked doors, fencing, gates, or other barriers;
(b) Posted signs and notices at conspicuous locations, such as at normal points of entry and at reasonable intervals along the boundary of the closed area; or
(c) Other reasonably obvious means including, but not limited to, onsite personal contact with a uniformed official.