Cal. Water Code § 36579

If the board elects to have land within the district valued pursuant to Sections 36577 and 36578, the board may also provide for more than one schedule of valuations based upon different benefits bestowed on the land and the assignment of more than one valuation to the lands in the district and the levy of a separate assessment for the different benefits bestowed on the land. If the board elects to provide for separate valuations for separate benefits pursuant to this section, this chapter shall apply to the separate assessments. The assessment book shall include all assessments, but the assessor may, at his or her option, prepare separate assessment statements.