Maricopa County Department of Transportation (MCDOT) plans, designs, constructs, and maintains roadways primarily within the unincorporated areas of the county. MCDOT currently operates and maintains approximately 2,500 miles of roadway, more than 80 bridges, over 325 culverts, more than 160 signalized intersections, and approximately 35,000 traffic signs. MCDOT's funding is primarily derived from Highway User Revenue Fund (HURF) monies and some federal-aid highway funding.
MCDOT's mission is to provide transportation infrastructure (primarily roads) and related services to the people within Maricopa County so they can live, work, conduct business, and travel in a safe environment. MCDOT is led by the Transportation Director and is governed by the Maricopa County Board of Supervisors.
The statutory authority for MCDOT's work is derived primarily from A.R.S. Title 11, Chapter 2, Article 4 (Board of Supervisors), Title 11, Chapter 3, Article 9 (County Engineer) and Title 28, Chapter 19, Article 1 (County Highways). The Department's work is largely governed by the transportation laws of the State of Arizona (A.R.S. Title 28, generally).
MCDOT is largely a full service transportation agency, but does have some limited regulatory roles. These relate to adherence to County road standards, review of all development submittals that have impacts to county roads, and ensuring safe and responsible work in County right-of-way. MCDOT also works very closely with the Arizona Department of Transportation (ADOT), the Maricopa Association of Governments (MAG), incorporated cities, towns, and Indian communities.