Section 9475 Of Chapter 13. Validating Proceedings From California Streets And Highways Code >> Division 11. >> Chapter 13.

. After the reassessment has been confirmed it shall not be contested in any way other than at the time and in the manner specified in this chapter, and in any such action all findings, conclusions, and determinations of the legislative body which conducted the reassessment proceedings shall be conclusive in the absence of actual fraud.