Water Code § 51872
ARTICLE 4. Erroneous Assessments and Invalid Calls
When a parcel is sold by the county treasurer for nonpayment of a call of an installment of any assessment which is thereafter adjudged invalid by a court of competent jurisdiction, the court shall have power to set aside any and all proceedings or acts taken or had in connection with such sale and to cancel any certificate of sale and any deed made in pursuance of the sale.