Gov. Code, § 31899.4

(a) Each county and district shall provide a program to replace the benefits that are limited by Section 415 of the Internal Revenue Code for members whose retirement benefits are limited by Section 415 and cannot be fully maximized pursuant to Section 31538. The replacement benefits program shall provide benefits that, together with the benefits provided by the retirement system, are the same as, and may not exceed, the benefits that would be paid by the retirement system but for the application of the limits of Section 415. Notwithstanding the foregoing, the county or district may modify its replacement benefits program and may add, modify, or eliminate any replacement benefits, as necessary, to carry out the purpose of this chapter. A replacement benefit may not be reduced if the reduction would impair the vested rights of any person.

(b) Each county shall establish and administer its own replacement benefits program for members whose retirement benefits are limited by Section 415 of the Internal Revenue Code.

(c) A county may, pursuant to a contract with a district, agree to administer the district’s replacement benefits program for the district’s members whose retirement benefits are limited by Section 415 of the Internal Revenue Code. The county may charge each district a reasonable fee for administering the district’s program and the county and district may agree on any other conditions relating to that administration. If a district does not contract with the county to administer its replacement benefits program, it shall establish and administer its own replacement benefits program.

(d) Upon the recommendation of the retirement system’s actuary, and in accordance with its obligation to recommend county and district contribution rates under Sections 31453 and 31453.5, the board shall adjust the contributions required to be made by a county or district to the extent that benefits are payable under a replacement benefits program of that county or district.

(e) The county, and any district that establishes and administers its own program, shall enact an ordinance or prescribe regulations or other written documentation setting forth the terms of its replacement benefits program.

(f) Notwithstanding any other provision of this chapter, a county of the first class, as defined in Section 28020, as amended by Chapter 1204 of the Statutes of 1971, and Section 28022, as amended by Chapter 43 of the Statutes of 1961, is not required to provide replacement benefits to any member under this section if that member participates in General Plan F or Safety Plan F under Article 2.1 (commencing with Section 31510) of Chapter 3.