Understanding the need to provide reliable, high frequency transit from St. Paul, Minnesota to the northeast suburbs, Ramsey County took the lead in initiating project planning for a 15-mile bus rapid transit (BRT) route. The Rush Line BRT project will provide stops between Union Depot multimodal transportation hub in Lowertown St. Paul through the northeastern portions of St. Paul and into Maplewood, Gem Lake, Vadnais Heights and White Bear Lake. The project’s ultimate goals are to help satisfy long-term regional mobility and accessibility needs for businesses and the public, as well as support sustainable development within the corridor. When complete, this project will connect the community to 106,000 jobs within a 10-minute walk of the 21 planned stations.
Coordinated Geotechnical and Environmental Approaches
As part of the environmental review and preliminary design process, the design team selected Braun Intertec to complete a Phase I Environmental Site Assessment, Phase II Environmental Site Assessment and Preliminary Geotechnical Evaluation. The goals of these tasks were to assess the project’s risk for encountering contamination (with results to be incorporated in the project’s Environmental Assessment) and provide preliminary structure foundation recommendations – all information crucial in project planning and estimating.
This project was divided into five distinct areas based on geography and planned construction features to break the investigations into smaller, more manageable sections. Previous research of this project corridor indicated that from as early as the late 1800’s buildings along each of the five sections were developed for residential, commercial (including gasoline filling/service stations) and industrial uses. One section of the corridor even included an old railroad yard with known contaminated soil and debris below ground surface. In total, Braun Intertec drilled almost 140 soil borings within the project corridor to collect geotechnical and environmental data simultaneously for use in guiding property acquisition and design features such as bridges, guideway, stations, and stormwater best management practices (BMPs).
Benefits for Coordinated Approaches
The approach of combining environmental and geotechnical borings saved the project approximately $250,000 in drilling and project management costs. An additional benefit of this coordinated approach minimized disruption to nearby residences and commercial businesses, who represent a large portion of the potential ridership. The combination of concurrent geotechnical and environmental consulting allowed for important environmental information to be incorporated into the overall environmental review process and preliminary design.
“The coordinated geotechnical and environmental insight that Braun Intertec was able to bring to our project was vital to completing the environmental assessment and helped in developing the preliminary design plans for the Rush Line BRT project,” said Andrew Gitzlaff, Senior Transportation Planner at Ramsey County. “These combined technical aspects simplified decision making and cut project costs at a crucial time for getting the project off the ground.”
