California Code, Streets and Highways Code - SHC § 8251

Upon dissolution of a district containing a single city, any property which may have been acquired by the district shall vest in the city, except projects theretofore transferred and conveyed to the county under the provisions of Chapter 11 of this part.

Upon dissolution of a district containing two or more cities, undisposed of property shall be distributed by the commission to the cities by a formula based on the assessed valuation of property contained in the cities as shown on the last equalized assessment roll of the county.