Chicago Range Erosion Control Project

The Design-Build Contractor (DBC) is the single point of responsibility for the performance of contractual requirements. By utilizing performance-based requirements the Government has appropriately shifted the responsibility for making most design decisions to the DBC. The goal of this Design-Build Project is to provide an engineered solutions that can be designed and constructed (within the budget) that will address as many, if not all, the most serious erosion problems at the Chicago Regional Training Facility.

The Design-Build Contractor shall institute and foster an innovative, effective, and efficient management program able to address changes and developing conditions while continuing to maintain appropriately high levels of quality within budget constraints. Lake Michigan continues to create erosion distresses which are plaquing the site. The lake’s waves batter the shoreline persistently.

Above the shoreline, the top of the bluff has been susceptible to shifting soil and stormwater run-off which has led to failed soils and erosion. Storms and wave action has caused erosion and slippage of the slope while wave action at the toe of the bluff has slowly eroded the shoreline and undermined the bluff. The Government hired a contractor several years ago to address these concerns and stabilize the bluff to prevent the continued erosion.

The contractor installed a sheet pile retaining wall at the top of the bluff from the south running along the bluff to the north but failed to extend the wall the last 50-75 feet at the northern portion. They also sloped the top of the bluff to direct storm run-off into drainage swells that directed the water to a drainpipe that daylighted above the toe. The grading was found to be insufficient, and the missing portion of the wall allowed for continued erosion of the bluff.

Repairs were made to the existing access road leading from the top of the bluff to the toe, however lack of adequate storm water drainage has scoured the aggregate surface. Erosion at the northeast portion of the bluff has already caused debris to wash onto the adjacent landowner’s property and continue to see the bluff slide towards Lake Michigan.

Grading work performed under the previous contract which was performed close to the northern property boundary was not sufficiently compacted which has allowed continued erosion causing debris to wash onto the adjacent landowner’s property and continue to see the bluff slide towards Lake Michigan. Stormwater ponding is also occurring adjacent to the retaining wall at the top of the bluff due to the grading issues that have restricted the volume of vehicles that can park in the area from what was original planned.

There also appears to be a continuously flowing leak originating from an existing manhole that provides drainage from the firing range on site to the top of the bluff where the runoff appears to overflow the top to the exposed bluff helping to cause the continued erosion. The project’s primary goal is to stabilize the remaining portion of the bluff and properly divert the stormwater run-off to the outfall and into Lake Michigan.