20 More Years of Transportation Investment Celebrated with Groundbreaking On Friday, March 6, Proposition 479, the future of transportation in the region, was celebrated by state and local officials, the business community, and transportation infrastructure partners. Prop 479 is the continuation of an existing, dedicated half-cent sales tax in Maricopa County to fund transportation. The half-cent sales tax was first established by voters in 1985, with the approval of Proposit