(a) The Legislature hereby finds and declares that a county may face substantial expense in maintaining a roll or system which reflects both current values of property for purposes of ad valorem benefit assessments as well as the property values for general taxation mandated by Article XIII A of the California Constitution. The Legislature further finds and declares that a fair and proper benefit assessment for flood control purposes may be levied on the alternative basis of the use to which the benefited land in a maintenance area may be put.

(b) The board of supervisors of the county may evaluate the costs of maintaining a system to determine benefits according to assessed valuation of land and improvements thereon pursuant to Section 12878.35. If the board of supervisors finds that these costs would be excessive relative to the amounts to be collected, it may, in lieu of an ad valorem benefit assessment, elect to levy a benefit assessment as set forth in this section sufficient to raise the amount or amounts certified by the department. Amounts raised pursuant to this section for transmittal to the department shall be in lieu of any apportionment of county property tax revenues to the support of the maintenance area pursuant to Chapter 6 (commencing with Section 95) of Part 0.5 of Division 1 of the Revenue and Taxation Code. The assessment authorized to be levied on each parcel under this section shall be based upon the parcel’s proportionate benefit, expressed as a product of the degree of flood protection it receives, its size, and its capacity for being put to use, with respect to all other parcels in the maintenance area. Specifically, a parcel’s benefit product equals the percentage benefit for the zone in which the parcel is located, as defined in Section 12878.9, multiplied by the acreage of the parcel, multiplied by the parcel’s land use factor as specified in subdivision (c). Any parcel less than one-third acre in size shall be deemed to be one-third acre. For any parcel categorized as agriculture in subdivision (c), every acre over five acres shall be deemed to be one-tenth acre.

(c) The county shall assign each parcel to one of the following land use categories, representing its current predominant land use capability, and shall assign to each parcel the land use factor corresponding to such category:

Prior to April 1 of any year, landowners in the maintenance area may petition the board of supervisors, or the board of supervisors may on its own motion elect, to review the land use categories and land use factors herein provided. The petition shall be signed by at least 50 landowners or 10 percent of the landowners in the maintenance area, whichever is less. The board of supervisors shall thereupon give notice, pursuant to § 6066 of the Government Code, and hold a hearing to determine whether the land use categories should be modified or increased in number and whether the land use factors should be modified. The board of supervisors may, by resolution, modify the categories and factors as in its judgment is required for fair and practical special benefit assessments for flood control maintenance. The board of supervisors may delegate to an appropriate county board or administrative body the powers and duties set forth in this subdivision.

(d) The amount assessed each parcel in the maintenance area shall be determined by the following formula: the benefit product of the parcel multiplied by the total amount to be collected in the maintenance area, divided by the sum of the various benefit products of all parcels in the maintenance area.

(e) If the county board of supervisors elects to use the benefit assessment procedure and formula provided in this section, the county may recover the reasonable costs of its services in preparing and levying the assessments. The board of supervisors shall add the amount for estimated county costs to the amount or amounts certified by the department and shall include that amount in the benefit assessment levied pursuant to this section.

(f) All other provisions of this chapter applicable to the levy of assessments shall apply to this section so far as they are or may be made applicable.

(Added by Stats. 1982, Ch. 759, Sec. 4. Effective September 8, 1982.)