California Code, Streets and Highways Code - SHC § 22646

The assessments shall be collected at the same time and in the same manner as county taxes are collected, and all laws providing for the collection and enforcement of county taxes shall apply to the collection and enforcement of the assessments, except that assessments levied pursuant to Section 22660 for which bonds or notes are to be issued may be paid within 30 days after the date the county auditor has entered the assessments on the county assessment roll, upon which time the engineer shall make and file with the treasurer a complete list of all unpaid assessments in the manner required by Section 8620.  As a cumulative remedy, assessments and related charges and penalties, to pay principal or interest on bonds or notes, which are not paid when due, may be collected by an action brought in superior court, pursuant to Part 14 (commencing with Section 8830) of Division 10.