Mitchell has also helped secure funding for the new Valley Metro light rail system, which, in addition to providing greater access to area business, education, sports, and cultural locations, is also generating a significant economic impact in its own right. According to Valley Metro, public and private economic impact is estimated to reach $7 billion.

Representative Mitchell is also challenging outdated funding formulas to help Arizona get its fair share of federal funding. Mitchell successfully changed federal highway law to make priority projects in Arizona eligible for a higher federal share of federal funding. He has also working to change an antiquated wastewater infrastructure formula that is so outdated that it ranks Arizona 53rd among states and territories in per capita receipt of federal funding, despite ranking 9th in the nation in need.

The American Recovery and Reinvestment Act of 2009, which Congressman Mitchell supported is expected to provide nearly $649 million for Arizona's transportation and infrastructure needs.

Representative Mitchell's support for transportation was recognized by the South West Transit Association which named him the 2009 Legislator of the Year. The annual award recognizes a member of the U.S. House or Senate who has significantly advanced the interest of public transportation in the previous year.