Cal. Sts. & High. Code § 5508

The street superintendent shall thereupon record the reassessment with a certificate at the end thereof by the clerk, that it is the reassessment approved by the legislative body. He shall also note opposite the several assessments in the original assessment that have been displaced by the reassessment the fact that the reassessment has been made, giving its date, and shall credit upon such reassessment all payments theretofore made upon the original assessment, or upon the bonds issued to represent the original assessment, together with interest on such payments at the rate of 7 per cent per year from and after the date of such payments.