California Code, Streets and Highways Code - SHC § 301.3

(a) The commission may relinquish to the City of Newport Beach the portion of Route 1 that is located between Jamboree Road and the Santa Ana River, within the city limits of the City of Newport Beach, upon terms and conditions the commission finds to be in the best interests of the state.

(b) A relinquishment under this section shall become effective immediately following the county recorder's recordation of the relinquishment resolution containing the commission's approval of the terms and conditions of the relinquishment.

(c) On and after the effective date of the relinquishment, both of the following shall occur:

(d) The City of Newport Beach shall ensure the continuity of traffic flow on the relinquished portions of Route 1, including, but not limited to, any traffic signal progression.

(e) For those portions of Route 1 that are relinquished, the City of Newport Beach shall maintain within its jurisdiction signs directing motorists to the continuation of Route 1.