South Mountain Loop 202 in Maricopa County, Arizona is a proposed new highway providing a connection from the South Valley and West Valley without going through downtown Phoenix. The study examined how the proposed highway could potentially strengthen economic connections between three MPOs in the Sun Corridor megaregion: the Maricopa Association of Governments (MAG), the Pima Association of Governments (PAG) and the Sun Corridor MPO, and improve equity for rural areas. The study used a Value Impact Analysis (VIA) framework that extended TREDIS to accept additional accessibility and land value data to assess potential regional economic development and equity impacts.
The travel model provided daily data by time of day, mode, and trip purpose for build and no-build for 2025 and 2040. TREDIS automatically linearly interpolated and extrapolated annual values. It assessed inter-regional benefits from improved economic ties between the MAG region and the outlying PAG region, as well as access increases affecting parallel routes and outlying areas. The VIA tool provided a means to drill down to specific populations such as low-income residents and Native American tribes.