CA Pub Util Code Section 150206

(a)

The authority, subject to the approval of the voters, may impose a maximum tax rate of 1 percent under this division and Part 1.6 (commencing with Section 7251) of Division 2 of the Revenue and Taxation Code, and the authority may state the maximum tax rate at 1 percent or one-half of 1 percent. The authority shall not levy the retail transactions and use tax at a rate other than 1 percent or one-half of 1 percent, unless specifically authorized by the Legislature.

(b)

The tax rate adopted pursuant to this chapter, unless otherwise prohibited, may be increased by the authority by ordinance adopted in the manner and by the vote stated in Sections 150201 and approved by a majority of the electors voting on the measure at an election called for that purpose.