Cal. PRC § 5540.6

Notwithstanding Section 5540, a district may, with the approval by a four-fifths vote of the board of directors, convey to another public agency any real property, or any interest in real property, dedicated and used for park or open-space purposes, or both, provided the public agency undertakes in a recorded written agreement to continue to use the real property, or the interest in the real property, for those purposes and not to convey the real property, or the interest in the real property, without the consent of a majority of the voters of the district at an election called and conducted by the board pursuant to Section 5540.