Cal. Public Contract Code § 21012

Whenever upon the hearing in Section 21011 provided, whether original or continued, the board shall be of the opinion that the work has been completed and done according to the contract, said board shall by resolution to be entered upon its minutes so declare, and shall in said resolution declare that the work is accepted and the amount of the contract price for doing the work and the amount of the incidental costs and expenses of the work and proceedings and the aggregate amount for which bonds are to be issued and shall make final order that bonds be issued therefor as hereinafter provided. The decision and determination of said board at the hearing provided for in Section 21011 shall, as to all matters determined at said hearing and as to all errors, informalities, irregularities, or omissions which said board might have avoided or remedied during the progress of the proceedings, or which it can at that time remedy, be final and conclusive upon all persons entitled to be heard before said board on said matters, and no assessment or tax levied for the payment of the bonds, and the interest thereon, to be issued for said work and expenses, shall be held invalid by any court for any error, informality, omission, or other defect in the proceedings where the resolution of intention has been actually published as in this act provided, before the said board shall have ordered the work to be done.