Lowest Stemmons is a 2.3-mile, $109 million project designed to ease congestion in Dallas on I-35E from I-30 to north of Oak Lawn Avenue. This complex urban highway project, with a nearly 300,000 annual average daily traffic (AADT) volume in 2017, involves building bridges, ramps and frontage roads through the densely populated downtown area. To the south, the project ties into the Dallas Horseshoe and Southern Gateway projects.
Lowest Stemmons, located directly adjacent to Dallas Area Rapid Transit (DART) and Trinity Railway Express commuter rail lines, is constrained by a limited right-of-way. The project’s complex utilities include overhead electrical transmission lines and three underground lines as well as 20 fiberoptic and phone lines. The project includes construction of a new $7 million wastewater main with a temporary multiple bypass required to connect the system. The project also encompasses a new TxDOT Intelligent Transportation Systems (ITS) system with Closed Circuit Television (CCTV) cameras, radar vehicle sensing devices (RVSD) and message boards as part of the system.
In addition, Lowest Stemmons requires compliance with a TxDOT Soil and Groundwater Management Plan that governs all handling, management and disposal of soils and groundwater to avoid contamination from a former municipal solid waste landfill in the area.
Lowest Stemmons reduces congestion, improves mobility, increases operational efficiency, makes travel times more reliable and lowers fuel consumption. The project leverages funding from the Texas Clear Lanes Initiative to provide operational improvements to the congested I-35E corridor, including collector-distributor roads (north and southbound), direct connectors, reconstructed ramps and bridge structures to accommodate the improvements.