CA Health & Safety Code Section 2862.5

The cost of abating a nuisance shall be repaid to the district by the owner of the property. However, the owner shall not be required to pay for the costs unless, either prior to or subsequent to the abatement by the district, a hearing is held by the district board, at which the property owner is afforded an opportunity to be heard, and the district board determines that a nuisance actually exists or that a nuisance existed prior to the abatement by the district.