(

a) The Legislature, by the enactment of this

chapter intends a county transportation authority or the commission, pursuant to a county transportation expenditure plan adopted pursuant to

Section 131055, to use any additional funds provided by this

chapter to supplement existing local revenues being used for public transportation purposes listed in the plan. The Legislature further intends that the funds provided pursuant to this

chapter shall not replace funds previously provided by property tax revenues for public transportation purposes. The nine-county San Francisco Bay area is further encouraged to maintain its existing commitment of local funds for public transportation purposes. (

b) Any tax revenue generated pursuant to this

chapter shall be expended in the county of origin, except that tax revenue generated may be expended within and outside the county of origin if so provided in the adopted county transportation expenditure plan. However, the tax revenues may be exchanged for federal or state funds available to another county or local government for transportation purposes if the exchange will benefit the county of origin. (c)

(1) In order to receive funds from the Counties of Alameda and Contra Costa and the City and County of San Francisco pursuant to this chapter, the San Francisco Bay Area Rapid Transit District shall agree to match from federal, state, or other funds available to the district, at least as much as it receives from the additional funds provided by this

chapter from those counties.

(2) The funds the district received pursuant to this chapter, and its matching funds therefor, shall be used only for capital expenditures.