Undercutting & Surfacing MDW
This map shows the location of the project. For projects that do not have a specific location but affect a line/route or the entire system, either the affected lines/routes are shown, or an entire service area map is shown.
If you select the option to “toggle the benefit layer,” you will see an approximation of the area that will benefit from the project.
Each capital project is measured on 15 evaluation metrics to better understand its impact on the region. Learn more about the metrics and see a legend for all measures here.
Click the circled (i) information button to read a definition of each metric and hover over the image to see more about each measure.
Project programmed before 2024; Not evaluated by these metrics.
Project Description
Track undercutting provides for the removal of all fouled track ballast, which is then cleaned and returned to the track bed. When the ballast is fouled, the load spreading capability is lost. Undercutting is necessary when the ballast section has become so contaminated that normal ballasting and surfacing will no longer hold a proper track surface. The results of undercutting are a smooth, well-aligned track surface, extended tie and ballast life and reduced ongoing maintenance expense.